| 1 | |
| 2 | |
| 3 | * Copyright (C) 1999 Eric Youngdale
|
| 4 | * Copyright (C) 2014 Christoph Hellwig
|
| 5 | *
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| 6 | * SCSI queueing library.
|
| 7 | * Initial versions: Eric Youngdale ([email protected]).
|
| 8 | * Based upon conversations with large numbers
|
| 9 | * of people at Linux Expo.
|
| 10 |
|
| 11 |
|
| 12 | #include <linux/bio.h>
|
| 13 | #include <linux/bitops.h>
|
| 14 | #include <linux/blkdev.h>
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| 15 | #include <linux/completion.h>
|
| 16 | #include <linux/ctype.h>
|
| 17 | #include <linux/kernel.h>
|
| 18 | #include <linux/export.h>
|
| 19 | #include <linux/init.h>
|
| 20 | #include <linux/pci.h>
|
| 21 | #include <linux/delay.h>
|
| 22 | #include <linux/hardirq.h>
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| 23 | #include <linux/scatterlist.h>
|
| 24 | #include <linux/blk-mq.h>
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| 25 | #include <linux/blk-integrity.h>
|
| 26 | #include <linux/ratelimit.h>
|
| 27 | #include <linux/unaligned.h>
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| 28 |
|
| 29 | #include <scsi/scsi.h>
|
| 30 | #include <scsi/scsi_cmnd.h>
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| 31 | #include <scsi/scsi_dbg.h>
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| 32 | #include <scsi/scsi_device.h>
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| 33 | #include <scsi/scsi_driver.h>
|
| 34 | #include <scsi/scsi_eh.h>
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| 35 | #include <scsi/scsi_host.h>
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| 36 | #include <scsi/scsi_transport.h>
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| 37 | #include <scsi/scsi_dh.h>
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| 38 |
|
| 39 | #include <trace/events/scsi.h>
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| 40 |
|
| 41 | #include "scsi_debugfs.h"
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| 42 | #include "scsi_priv.h"
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| 43 | #include "scsi_logging.h"
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| 44 |
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| 45 | |
| 46 | * Size of integrity metadata is usually small, 1 inline sg should
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| 47 | * cover normal cases.
|
| 48 |
|
| 49 | #ifdef CONFIG_ARCH_NO_SG_CHAIN
|
| 50 | #define SCSI_INLINE_PROT_SG_CNT 0
|
| 51 | #define SCSI_INLINE_SG_CNT 0
|
| 52 | #else
|
| 53 | #define SCSI_INLINE_PROT_SG_CNT 1
|
| 54 | #define SCSI_INLINE_SG_CNT 2
|
| 55 | #endif
|
| 56 |
|
| 57 | static struct kmem_cache *scsi_sense_cache;
|
| 58 | static DEFINE_MUTEX(scsi_sense_cache_mutex);
|
| 59 |
|
| 60 | static void scsi_mq_uninit_cmd(struct scsi_cmnd *cmd);
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| 61 |
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| 62 | int scsi_init_sense_cache(struct Scsi_Host *shost)
|
| 63 | {
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| 64 | int ret = 0;
|
| 65 |
|
| 66 | mutex_lock(&scsi_sense_cache_mutex);
|
| 67 | if (!scsi_sense_cache) {
|
| 68 | scsi_sense_cache =
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| 69 | kmem_cache_create_usercopy("scsi_sense_cache",
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| 70 | SCSI_SENSE_BUFFERSIZE, 0, SLAB_HWCACHE_ALIGN,
|
| 71 | 0, SCSI_SENSE_BUFFERSIZE, NULL);
|
| 72 | if (!scsi_sense_cache)
|
| 73 | ret = -ENOMEM;
|
| 74 | }
|
| 75 | mutex_unlock(&scsi_sense_cache_mutex);
|
| 76 | return ret;
|
| 77 | }
|
| 78 |
|
| 79 | static void
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| 80 | scsi_set_blocked(struct scsi_cmnd *cmd, enum scsi_qc_status reason)
|
| 81 | {
|
| 82 | struct Scsi_Host *host = cmd->device->host;
|
| 83 | struct scsi_device *device = cmd->device;
|
| 84 | struct scsi_target *starget = scsi_target(device);
|
| 85 |
|
| 86 | |
| 87 | * Set the appropriate busy bit for the device/host.
|
| 88 | *
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| 89 | * If the host/device isn't busy, assume that something actually
|
| 90 | * completed, and that we should be able to queue a command now.
|
| 91 | *
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| 92 | * Note that the prior mid-layer assumption that any host could
|
| 93 | * always queue at least one command is now broken. The mid-layer
|
| 94 | * will implement a user specifiable stall (see
|
| 95 | * scsi_host.max_host_blocked and scsi_device.max_device_blocked)
|
| 96 | * if a command is requeued with no other commands outstanding
|
| 97 | * either for the device or for the host.
|
| 98 |
|
| 99 | switch (reason) {
|
| 100 | case SCSI_MLQUEUE_HOST_BUSY:
|
| 101 | atomic_set(&host->host_blocked, host->max_host_blocked);
|
| 102 | break;
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| 103 | case SCSI_MLQUEUE_DEVICE_BUSY:
|
| 104 | case SCSI_MLQUEUE_EH_RETRY:
|
| 105 | atomic_set(&device->device_blocked,
|
| 106 | device->max_device_blocked);
|
| 107 | break;
|
| 108 | case SCSI_MLQUEUE_TARGET_BUSY:
|
| 109 | atomic_set(&starget->target_blocked,
|
| 110 | starget->max_target_blocked);
|
| 111 | break;
|
| 112 | }
|
| 113 | }
|
| 114 |
|
| 115 | static void scsi_mq_requeue_cmd(struct scsi_cmnd *cmd, unsigned long msecs)
|
| 116 | {
|
| 117 | struct request *rq = scsi_cmd_to_rq(cmd);
|
| 118 |
|
| 119 | if (rq->rq_flags & RQF_DONTPREP) {
|
| 120 | rq->rq_flags &= ~RQF_DONTPREP;
|
| 121 | scsi_mq_uninit_cmd(cmd);
|
| 122 | } else {
|
| 123 | WARN_ON_ONCE(true);
|
| 124 | }
|
| 125 |
|
| 126 | blk_mq_requeue_request(rq, false);
|
| 127 | if (!scsi_host_in_recovery(cmd->device->host))
|
| 128 | blk_mq_delay_kick_requeue_list(rq->q, msecs);
|
| 129 | }
|
| 130 |
|
| 131 | |
| 132 | * __scsi_queue_insert - private queue insertion
|
| 133 | * @cmd: The SCSI command being requeued
|
| 134 | * @reason: The reason for the requeue
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| 135 | * @unbusy: Whether the queue should be unbusied
|
| 136 | *
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| 137 | * This is a private queue insertion. The public interface
|
| 138 | * scsi_queue_insert() always assumes the queue should be unbusied
|
| 139 | * because it's always called before the completion. This function is
|
| 140 | * for a requeue after completion, which should only occur in this
|
| 141 | * file.
|
| 142 |
|
| 143 | static void __scsi_queue_insert(struct scsi_cmnd *cmd,
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| 144 | enum scsi_qc_status reason, bool unbusy)
|
| 145 | {
|
| 146 | struct scsi_device *device = cmd->device;
|
| 147 |
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| 148 | SCSI_LOG_MLQUEUE(1, scmd_printk(KERN_INFO, cmd,
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| 149 | "Inserting command %p into mlqueue\n", cmd));
|
| 150 |
|
| 151 | scsi_set_blocked(cmd, reason);
|
| 152 |
|
| 153 | |
| 154 | * Decrement the counters, since these commands are no longer
|
| 155 | * active on the host/device.
|
| 156 |
|
| 157 | if (unbusy)
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| 158 | scsi_device_unbusy(device, cmd);
|
| 159 |
|
| 160 | |
| 161 | * Requeue this command. It will go before all other commands
|
| 162 | * that are already in the queue. Schedule requeue work under
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| 163 | * lock such that the kblockd_schedule_work() call happens
|
| 164 | * before blk_mq_destroy_queue() finishes.
|
| 165 |
|
| 166 | cmd->result = 0;
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| 167 |
|
| 168 | blk_mq_requeue_request(scsi_cmd_to_rq(cmd),
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| 169 | !scsi_host_in_recovery(cmd->device->host));
|
| 170 | }
|
| 171 |
|
| 172 | |
| 173 | * scsi_queue_insert - Reinsert a command in the queue.
|
| 174 | * @cmd: command that we are adding to queue.
|
| 175 | * @reason: why we are inserting command to queue.
|
| 176 | *
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| 177 | * We do this for one of two cases. Either the host is busy and it cannot accept
|
| 178 | * any more commands for the time being, or the device returned QUEUE_FULL and
|
| 179 | * can accept no more commands.
|
| 180 | *
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| 181 | * Context: This could be called either from an interrupt context or a normal
|
| 182 | * process context.
|
| 183 |
|
| 184 | void scsi_queue_insert(struct scsi_cmnd *cmd, enum scsi_qc_status reason)
|
| 185 | {
|
| 186 | __scsi_queue_insert(cmd, reason, true);
|
| 187 | }
|
| 188 |
|
| 189 | |
| 190 | * scsi_failures_reset_retries - reset all failures to zero
|
| 191 | * @failures: &struct scsi_failures with specific failure modes set
|
| 192 |
|
| 193 | void scsi_failures_reset_retries(struct scsi_failures *failures)
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| 194 | {
|
| 195 | struct scsi_failure *failure;
|
| 196 |
|
| 197 | failures->total_retries = 0;
|
| 198 |
|
| 199 | for (failure = failures->failure_definitions; failure->result;
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| 200 | failure++)
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| 201 | failure->retries = 0;
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| 202 | }
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| 203 | EXPORT_SYMBOL_GPL(scsi_failures_reset_retries);
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| 204 |
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| 205 | |
| 206 | * scsi_check_passthrough - Determine if passthrough scsi_cmnd needs a retry.
|
| 207 | * @scmd: scsi_cmnd to check.
|
| 208 | * @failures: scsi_failures struct that lists failures to check for.
|
| 209 | *
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| 210 | * Returns -EAGAIN if the caller should retry else 0.
|
| 211 |
|
| 212 | static int scsi_check_passthrough(struct scsi_cmnd *scmd,
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| 213 | struct scsi_failures *failures)
|
| 214 | {
|
| 215 | struct scsi_failure *failure;
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| 216 | struct scsi_sense_hdr sshdr;
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| 217 | enum sam_status status;
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| 218 |
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| 219 | if (!scmd->result)
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| 220 | return 0;
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| 221 |
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| 222 | if (!failures)
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| 223 | return 0;
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| 224 |
|
| 225 | for (failure = failures->failure_definitions; failure->result;
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| 226 | failure++) {
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| 227 | if (failure->result == SCMD_FAILURE_RESULT_ANY)
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| 228 | goto maybe_retry;
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| 229 |
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| 230 | if (host_byte(scmd->result) &&
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| 231 | host_byte(scmd->result) == host_byte(failure->result))
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| 232 | goto maybe_retry;
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| 233 |
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| 234 | status = status_byte(scmd->result);
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| 235 | if (!status)
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| 236 | continue;
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| 237 |
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| 238 | if (failure->result == SCMD_FAILURE_STAT_ANY &&
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| 239 | !scsi_status_is_good(scmd->result))
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| 240 | goto maybe_retry;
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| 241 |
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| 242 | if (status != status_byte(failure->result))
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| 243 | continue;
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| 244 |
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| 245 | if (status_byte(failure->result) != SAM_STAT_CHECK_CONDITION ||
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| 246 | failure->sense == SCMD_FAILURE_SENSE_ANY)
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| 247 | goto maybe_retry;
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| 248 |
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| 249 | if (!scsi_command_normalize_sense(scmd, &sshdr))
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| 250 | return 0;
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| 251 |
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| 252 | if (failure->sense != sshdr.sense_key)
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| 253 | continue;
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| 254 |
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| 255 | if (failure->asc == SCMD_FAILURE_ASC_ANY)
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| 256 | goto maybe_retry;
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| 257 |
|
| 258 | if (failure->asc != sshdr.asc)
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| 259 | continue;
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| 260 |
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| 261 | if (failure->ascq == SCMD_FAILURE_ASCQ_ANY ||
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| 262 | failure->ascq == sshdr.ascq)
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| 263 | goto maybe_retry;
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| 264 | }
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| 265 |
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| 266 | return 0;
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| 267 |
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| 268 | maybe_retry:
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| 269 | if (failure->allowed) {
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| 270 | if (failure->allowed == SCMD_FAILURE_NO_LIMIT ||
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| 271 | ++failure->retries <= failure->allowed)
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| 272 | return -EAGAIN;
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| 273 | } else {
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| 274 | if (failures->total_allowed == SCMD_FAILURE_NO_LIMIT ||
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| 275 | ++failures->total_retries <= failures->total_allowed)
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| 276 | return -EAGAIN;
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| 277 | }
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| 278 |
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| 279 | return 0;
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| 280 | }
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| 281 |
|
| 282 | |
| 283 | * scsi_execute_cmd - insert request and wait for the result
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| 284 | * @sdev: scsi_device
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| 285 | * @cmd: scsi command
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| 286 | * @opf: block layer request cmd_flags
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| 287 | * @buffer: data buffer
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| 288 | * @bufflen: len of buffer
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| 289 | * @timeout: request timeout in HZ
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| 290 | * @ml_retries: number of times SCSI midlayer will retry request
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| 291 | * @args: Optional args. See struct definition for field descriptions
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| 292 | *
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| 293 | * Returns the scsi_cmnd result field if a command was executed, or a negative
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| 294 | * Linux error code if we didn't get that far.
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| 295 |
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| 296 | int scsi_execute_cmd(struct scsi_device *sdev, const unsigned char *cmd,
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| 297 | blk_opf_t opf, void *buffer, unsigned int bufflen,
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| 298 | int timeout, int ml_retries,
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| 299 | const struct scsi_exec_args *args)
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| 300 | {
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| 301 | static const struct scsi_exec_args default_args;
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| 302 | struct request *req;
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| 303 | struct scsi_cmnd *scmd;
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| 304 | int ret;
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| 305 |
|
| 306 | if (!args)
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| 307 | args = &default_args;
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| 308 | else if (WARN_ON_ONCE(args->sense &&
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| 309 | args->sense_len != SCSI_SENSE_BUFFERSIZE))
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| 310 | return -EINVAL;
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| 311 |
|
| 312 | retry:
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| 313 | req = scsi_alloc_request(sdev->request_queue, opf, args->req_flags);
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| 314 | if (IS_ERR(req))
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| 315 | return PTR_ERR(req);
|
| 316 |
|
| 317 | if (bufflen) {
|
| 318 | ret = blk_rq_map_kern(req, buffer, bufflen, GFP_NOIO);
|
| 319 | if (ret)
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| 320 | goto out;
|
| 321 | }
|
| 322 | scmd = blk_mq_rq_to_pdu(req);
|
| 323 | scmd->cmd_len = COMMAND_SIZE(cmd[0]);
|
| 324 | memcpy(scmd->cmnd, cmd, scmd->cmd_len);
|
| 325 | scmd->allowed = ml_retries;
|
| 326 | scmd->flags |= args->scmd_flags;
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| 327 | req->timeout = timeout;
|
| 328 | req->rq_flags |= RQF_QUIET;
|
| 329 |
|
| 330 | |
| 331 | * head injection *required* here otherwise quiesce won't work
|
| 332 |
|
| 333 | blk_execute_rq(req, true);
|
| 334 |
|
| 335 | if (scsi_check_passthrough(scmd, args->failures) == -EAGAIN) {
|
| 336 | blk_mq_free_request(req);
|
| 337 | goto retry;
|
| 338 | }
|
| 339 |
|
| 340 | |
| 341 | * Some devices (USB mass-storage in particular) may transfer
|
| 342 | * garbage data together with a residue indicating that the data
|
| 343 | * is invalid. Prevent the garbage from being misinterpreted
|
| 344 | * and prevent security leaks by zeroing out the excess data.
|
| 345 |
|
| 346 | if (unlikely(scmd->resid_len > 0 && scmd->resid_len <= bufflen))
|
| 347 | memset(buffer + bufflen - scmd->resid_len, 0, scmd->resid_len);
|
| 348 |
|
| 349 | if (args->resid)
|
| 350 | *args->resid = scmd->resid_len;
|
| 351 | if (args->sense)
|
| 352 | memcpy(args->sense, scmd->sense_buffer, SCSI_SENSE_BUFFERSIZE);
|
| 353 | if (args->sshdr)
|
| 354 | scsi_normalize_sense(scmd->sense_buffer, scmd->sense_len,
|
| 355 | args->sshdr);
|
| 356 |
|
| 357 | ret = scmd->result;
|
| 358 | out:
|
| 359 | blk_mq_free_request(req);
|
| 360 |
|
| 361 | return ret;
|
| 362 | }
|
| 363 | EXPORT_SYMBOL(scsi_execute_cmd);
|
| 364 |
|
| 365 | |
| 366 | * Wake up the error handler if necessary. Avoid as follows that the error
|
| 367 | * handler is not woken up if host in-flight requests number ==
|
| 368 | * shost->host_failed: use call_rcu() in scsi_eh_scmd_add() in combination
|
| 369 | * with an RCU read lock in this function to ensure that this function in
|
| 370 | * its entirety either finishes before scsi_eh_scmd_add() increases the
|
| 371 | * host_failed counter or that it notices the shost state change made by
|
| 372 | * scsi_eh_scmd_add().
|
| 373 |
|
| 374 | static void scsi_dec_host_busy(struct Scsi_Host *shost, struct scsi_cmnd *cmd)
|
| 375 | {
|
| 376 | unsigned long flags;
|
| 377 |
|
| 378 | rcu_read_lock();
|
| 379 | __clear_bit(SCMD_STATE_INFLIGHT, &cmd->state);
|
| 380 | if (unlikely(scsi_host_in_recovery(shost))) {
|
| 381 | |
| 382 | * Ensure the clear of SCMD_STATE_INFLIGHT is visible to
|
| 383 | * other CPUs before counting busy requests. Otherwise,
|
| 384 | * reordering can cause CPUs to race and miss an eh wakeup
|
| 385 | * when no CPU sees all busy requests as done or timed out.
|
| 386 |
|
| 387 | smp_mb();
|
| 388 |
|
| 389 | unsigned int busy = scsi_host_busy(shost);
|
| 390 |
|
| 391 | spin_lock_irqsave(shost->host_lock, flags);
|
| 392 | if (shost->host_failed || shost->host_eh_scheduled)
|
| 393 | scsi_eh_wakeup(shost, busy);
|
| 394 | spin_unlock_irqrestore(shost->host_lock, flags);
|
| 395 | }
|
| 396 | rcu_read_unlock();
|
| 397 | }
|
| 398 |
|
| 399 | void scsi_device_unbusy(struct scsi_device *sdev, struct scsi_cmnd *cmd)
|
| 400 | {
|
| 401 | struct Scsi_Host *shost = sdev->host;
|
| 402 | struct scsi_target *starget = scsi_target(sdev);
|
| 403 |
|
| 404 | scsi_dec_host_busy(shost, cmd);
|
| 405 |
|
| 406 | if (starget->can_queue > 0)
|
| 407 | atomic_dec(&starget->target_busy);
|
| 408 |
|
| 409 | if (sdev->budget_map.map)
|
| 410 | sbitmap_put(&sdev->budget_map, cmd->budget_token);
|
| 411 | cmd->budget_token = -1;
|
| 412 | }
|
| 413 |
|
| 414 | |
| 415 | * Kick the queue of SCSI device @sdev if @sdev != current_sdev. Called with
|
| 416 | * interrupts disabled.
|
| 417 |
|
| 418 | static void scsi_kick_sdev_queue(struct scsi_device *sdev, void *data)
|
| 419 | {
|
| 420 | struct scsi_device *current_sdev = data;
|
| 421 |
|
| 422 | if (sdev != current_sdev)
|
| 423 | blk_mq_run_hw_queues(sdev->request_queue, true);
|
| 424 | }
|
| 425 |
|
| 426 | |
| 427 | * Called for single_lun devices on IO completion. Clear starget_sdev_user,
|
| 428 | * and call blk_run_queue for all the scsi_devices on the target -
|
| 429 | * including current_sdev first.
|
| 430 | *
|
| 431 | * Called with *no* scsi locks held.
|
| 432 |
|
| 433 | static void scsi_single_lun_run(struct scsi_device *current_sdev)
|
| 434 | {
|
| 435 | struct Scsi_Host *shost = current_sdev->host;
|
| 436 | struct scsi_target *starget = scsi_target(current_sdev);
|
| 437 | unsigned long flags;
|
| 438 |
|
| 439 | spin_lock_irqsave(shost->host_lock, flags);
|
| 440 | starget->starget_sdev_user = NULL;
|
| 441 | spin_unlock_irqrestore(shost->host_lock, flags);
|
| 442 |
|
| 443 | |
| 444 | * Call blk_run_queue for all LUNs on the target, starting with
|
| 445 | * current_sdev. We race with others (to set starget_sdev_user),
|
| 446 | * but in most cases, we will be first. Ideally, each LU on the
|
| 447 | * target would get some limited time or requests on the target.
|
| 448 |
|
| 449 | blk_mq_run_hw_queues(current_sdev->request_queue,
|
| 450 | shost->queuecommand_may_block);
|
| 451 |
|
| 452 | spin_lock_irqsave(shost->host_lock, flags);
|
| 453 | if (!starget->starget_sdev_user)
|
| 454 | __starget_for_each_device(starget, current_sdev,
|
| 455 | scsi_kick_sdev_queue);
|
| 456 | spin_unlock_irqrestore(shost->host_lock, flags);
|
| 457 | }
|
| 458 |
|
| 459 | static inline bool scsi_device_is_busy(struct scsi_device *sdev)
|
| 460 | {
|
| 461 | if (scsi_device_busy(sdev) >= sdev->queue_depth)
|
| 462 | return true;
|
| 463 | if (atomic_read(&sdev->device_blocked) > 0)
|
| 464 | return true;
|
| 465 | return false;
|
| 466 | }
|
| 467 |
|
| 468 | static inline bool scsi_target_is_busy(struct scsi_target *starget)
|
| 469 | {
|
| 470 | if (starget->can_queue > 0) {
|
| 471 | if (atomic_read(&starget->target_busy) >= starget->can_queue)
|
| 472 | return true;
|
| 473 | if (atomic_read(&starget->target_blocked) > 0)
|
| 474 | return true;
|
| 475 | }
|
| 476 | return false;
|
| 477 | }
|
| 478 |
|
| 479 | static inline bool scsi_host_is_busy(struct Scsi_Host *shost)
|
| 480 | {
|
| 481 | if (atomic_read(&shost->host_blocked) > 0)
|
| 482 | return true;
|
| 483 | if (shost->host_self_blocked)
|
| 484 | return true;
|
| 485 | return false;
|
| 486 | }
|
| 487 |
|
| 488 | static void scsi_starved_list_run(struct Scsi_Host *shost)
|
| 489 | {
|
| 490 | LIST_HEAD(starved_list);
|
| 491 | struct scsi_device *sdev;
|
| 492 | unsigned long flags;
|
| 493 |
|
| 494 | spin_lock_irqsave(shost->host_lock, flags);
|
| 495 | list_splice_init(&shost->starved_list, &starved_list);
|
| 496 |
|
| 497 | while (!list_empty(&starved_list)) {
|
| 498 | struct request_queue *slq;
|
| 499 |
|
| 500 | |
| 501 | * As long as shost is accepting commands and we have
|
| 502 | * starved queues, call blk_run_queue. scsi_request_fn
|
| 503 | * drops the queue_lock and can add us back to the
|
| 504 | * starved_list.
|
| 505 | *
|
| 506 | * host_lock protects the starved_list and starved_entry.
|
| 507 | * scsi_request_fn must get the host_lock before checking
|
| 508 | * or modifying starved_list or starved_entry.
|
| 509 |
|
| 510 | if (scsi_host_is_busy(shost))
|
| 511 | break;
|
| 512 |
|
| 513 | sdev = list_entry(starved_list.next,
|
| 514 | struct scsi_device, starved_entry);
|
| 515 | list_del_init(&sdev->starved_entry);
|
| 516 | if (scsi_target_is_busy(scsi_target(sdev))) {
|
| 517 | list_move_tail(&sdev->starved_entry,
|
| 518 | &shost->starved_list);
|
| 519 | continue;
|
| 520 | }
|
| 521 |
|
| 522 | |
| 523 | * Once we drop the host lock, a racing scsi_remove_device()
|
| 524 | * call may remove the sdev from the starved list and destroy
|
| 525 | * it and the queue. Mitigate by taking a reference to the
|
| 526 | * queue and never touching the sdev again after we drop the
|
| 527 | * host lock. Note: if __scsi_remove_device() invokes
|
| 528 | * blk_mq_destroy_queue() before the queue is run from this
|
| 529 | * function then blk_run_queue() will return immediately since
|
| 530 | * blk_mq_destroy_queue() marks the queue with QUEUE_FLAG_DYING.
|
| 531 |
|
| 532 | slq = sdev->request_queue;
|
| 533 | if (!blk_get_queue(slq))
|
| 534 | continue;
|
| 535 | spin_unlock_irqrestore(shost->host_lock, flags);
|
| 536 |
|
| 537 | blk_mq_run_hw_queues(slq, false);
|
| 538 | blk_put_queue(slq);
|
| 539 |
|
| 540 | spin_lock_irqsave(shost->host_lock, flags);
|
| 541 | }
|
| 542 |
|
| 543 | list_splice(&starved_list, &shost->starved_list);
|
| 544 | spin_unlock_irqrestore(shost->host_lock, flags);
|
| 545 | }
|
| 546 |
|
| 547 | |
| 548 | * scsi_run_queue - Select a proper request queue to serve next.
|
| 549 | * @q: last request's queue
|
| 550 | *
|
| 551 | * The previous command was completely finished, start a new one if possible.
|
| 552 |
|
| 553 | static void scsi_run_queue(struct request_queue *q)
|
| 554 | {
|
| 555 | struct scsi_device *sdev = q->queuedata;
|
| 556 |
|
| 557 | if (scsi_target(sdev)->single_lun)
|
| 558 | scsi_single_lun_run(sdev);
|
| 559 | if (!list_empty(&sdev->host->starved_list))
|
| 560 | scsi_starved_list_run(sdev->host);
|
| 561 |
|
| 562 |
|
| 563 | blk_mq_kick_requeue_list(q);
|
| 564 | }
|
| 565 |
|
| 566 | void scsi_requeue_run_queue(struct work_struct *work)
|
| 567 | {
|
| 568 | struct scsi_device *sdev;
|
| 569 | struct request_queue *q;
|
| 570 |
|
| 571 | sdev = container_of(work, struct scsi_device, requeue_work);
|
| 572 | q = sdev->request_queue;
|
| 573 | scsi_run_queue(q);
|
| 574 | }
|
| 575 |
|
| 576 | void scsi_run_host_queues(struct Scsi_Host *shost)
|
| 577 | {
|
| 578 | struct scsi_device *sdev, *prev = NULL;
|
| 579 | unsigned long flags;
|
| 580 |
|
| 581 | spin_lock_irqsave(shost->host_lock, flags);
|
| 582 | __shost_for_each_device(sdev, shost) {
|
| 583 | |
| 584 | * Only skip devices so deep into removal they will never need
|
| 585 | * another kick to their queues. Thus scsi_device_get() cannot
|
| 586 | * be used as it would skip devices in SDEV_CANCEL state which
|
| 587 | * may need a queue kick.
|
| 588 |
|
| 589 | if (sdev->sdev_state == SDEV_DEL ||
|
| 590 | !get_device(&sdev->sdev_gendev))
|
| 591 | continue;
|
| 592 | spin_unlock_irqrestore(shost->host_lock, flags);
|
| 593 |
|
| 594 | if (prev)
|
| 595 | put_device(&prev->sdev_gendev);
|
| 596 | scsi_run_queue(sdev->request_queue);
|
| 597 |
|
| 598 | prev = sdev;
|
| 599 |
|
| 600 | spin_lock_irqsave(shost->host_lock, flags);
|
| 601 | }
|
| 602 | spin_unlock_irqrestore(shost->host_lock, flags);
|
| 603 | if (prev)
|
| 604 | put_device(&prev->sdev_gendev);
|
| 605 | }
|
| 606 |
|
| 607 | static void scsi_uninit_cmd(struct scsi_cmnd *cmd)
|
| 608 | {
|
| 609 | if (!blk_rq_is_passthrough(scsi_cmd_to_rq(cmd))) {
|
| 610 | struct scsi_driver *drv = scsi_cmd_to_driver(cmd);
|
| 611 |
|
| 612 | if (drv->uninit_command)
|
| 613 | drv->uninit_command(cmd);
|
| 614 | }
|
| 615 | }
|
| 616 |
|
| 617 | void scsi_free_sgtables(struct scsi_cmnd *cmd)
|
| 618 | {
|
| 619 | if (cmd->sdb.table.nents)
|
| 620 | sg_free_table_chained(&cmd->sdb.table,
|
| 621 | SCSI_INLINE_SG_CNT);
|
| 622 | if (scsi_prot_sg_count(cmd))
|
| 623 | sg_free_table_chained(&cmd->prot_sdb->table,
|
| 624 | SCSI_INLINE_PROT_SG_CNT);
|
| 625 | }
|
| 626 | EXPORT_SYMBOL_GPL(scsi_free_sgtables);
|
| 627 |
|
| 628 | static void scsi_mq_uninit_cmd(struct scsi_cmnd *cmd)
|
| 629 | {
|
| 630 | scsi_free_sgtables(cmd);
|
| 631 | scsi_uninit_cmd(cmd);
|
| 632 | }
|
| 633 |
|
| 634 | static void scsi_run_queue_async(struct scsi_device *sdev)
|
| 635 | {
|
| 636 | if (scsi_host_in_recovery(sdev->host))
|
| 637 | return;
|
| 638 |
|
| 639 | if (scsi_target(sdev)->single_lun ||
|
| 640 | !list_empty(&sdev->host->starved_list)) {
|
| 641 | kblockd_schedule_work(&sdev->requeue_work);
|
| 642 | } else {
|
| 643 | |
| 644 | * smp_mb() present in sbitmap_queue_clear() or implied in
|
| 645 | * .end_io is for ordering writing .device_busy in
|
| 646 | * scsi_device_unbusy() and reading sdev->restarts.
|
| 647 |
|
| 648 | int old = atomic_read(&sdev->restarts);
|
| 649 |
|
| 650 | |
| 651 | * ->restarts has to be kept as non-zero if new budget
|
| 652 | * contention occurs.
|
| 653 | *
|
| 654 | * No need to run queue when either another re-run
|
| 655 | * queue wins in updating ->restarts or a new budget
|
| 656 | * contention occurs.
|
| 657 |
|
| 658 | if (old && atomic_cmpxchg(&sdev->restarts, old, 0) == old)
|
| 659 | blk_mq_run_hw_queues(sdev->request_queue, true);
|
| 660 | }
|
| 661 | }
|
| 662 |
|
| 663 |
|
| 664 | static bool scsi_end_request(struct request *req, blk_status_t error,
|
| 665 | unsigned int bytes)
|
| 666 | {
|
| 667 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
|
| 668 | struct scsi_device *sdev = cmd->device;
|
| 669 | struct request_queue *q = sdev->request_queue;
|
| 670 |
|
| 671 | if (blk_update_request(req, error, bytes))
|
| 672 | return true;
|
| 673 |
|
| 674 | if (q->limits.features & BLK_FEAT_ADD_RANDOM)
|
| 675 | add_disk_randomness(req->q->disk);
|
| 676 |
|
| 677 | WARN_ON_ONCE(!blk_rq_is_passthrough(req) &&
|
| 678 | !(cmd->flags & SCMD_INITIALIZED));
|
| 679 | cmd->flags = 0;
|
| 680 |
|
| 681 | |
| 682 | * Calling rcu_barrier() is not necessary here because the
|
| 683 | * SCSI error handler guarantees that the function called by
|
| 684 | * call_rcu() has been called before scsi_end_request() is
|
| 685 | * called.
|
| 686 |
|
| 687 | destroy_rcu_head(&cmd->rcu);
|
| 688 |
|
| 689 | |
| 690 | * In the MQ case the command gets freed by __blk_mq_end_request,
|
| 691 | * so we have to do all cleanup that depends on it earlier.
|
| 692 | *
|
| 693 | * We also can't kick the queues from irq context, so we
|
| 694 | * will have to defer it to a workqueue.
|
| 695 |
|
| 696 | scsi_mq_uninit_cmd(cmd);
|
| 697 |
|
| 698 | |
| 699 | * queue is still alive, so grab the ref for preventing it
|
| 700 | * from being cleaned up during running queue.
|
| 701 |
|
| 702 | percpu_ref_get(&q->q_usage_counter);
|
| 703 |
|
| 704 | __blk_mq_end_request(req, error);
|
| 705 |
|
| 706 | scsi_run_queue_async(sdev);
|
| 707 |
|
| 708 | percpu_ref_put(&q->q_usage_counter);
|
| 709 | return false;
|
| 710 | }
|
| 711 |
|
| 712 | |
| 713 | * scsi_result_to_blk_status - translate a SCSI result code into blk_status_t
|
| 714 | * @result: scsi error code
|
| 715 | *
|
| 716 | * Translate a SCSI result code into a blk_status_t value.
|
| 717 |
|
| 718 | static blk_status_t scsi_result_to_blk_status(int result)
|
| 719 | {
|
| 720 | |
| 721 | * Check the scsi-ml byte first in case we converted a host or status
|
| 722 | * byte.
|
| 723 |
|
| 724 | switch (scsi_ml_byte(result)) {
|
| 725 | case SCSIML_STAT_OK:
|
| 726 | break;
|
| 727 | case SCSIML_STAT_RESV_CONFLICT:
|
| 728 | return BLK_STS_RESV_CONFLICT;
|
| 729 | case SCSIML_STAT_NOSPC:
|
| 730 | return BLK_STS_NOSPC;
|
| 731 | case SCSIML_STAT_MED_ERROR:
|
| 732 | return BLK_STS_MEDIUM;
|
| 733 | case SCSIML_STAT_TGT_FAILURE:
|
| 734 | return BLK_STS_TARGET;
|
| 735 | case SCSIML_STAT_DL_TIMEOUT:
|
| 736 | return BLK_STS_DURATION_LIMIT;
|
| 737 | }
|
| 738 |
|
| 739 | switch (host_byte(result)) {
|
| 740 | case DID_OK:
|
| 741 | if (scsi_status_is_good(result))
|
| 742 | return BLK_STS_OK;
|
| 743 | return BLK_STS_IOERR;
|
| 744 | case DID_TRANSPORT_FAILFAST:
|
| 745 | case DID_TRANSPORT_MARGINAL:
|
| 746 | return BLK_STS_TRANSPORT;
|
| 747 | default:
|
| 748 | return BLK_STS_IOERR;
|
| 749 | }
|
| 750 | }
|
| 751 |
|
| 752 | |
| 753 | * scsi_rq_err_bytes - determine number of bytes till the next failure boundary
|
| 754 | * @rq: request to examine
|
| 755 | *
|
| 756 | * Description:
|
| 757 | * A request could be merge of IOs which require different failure
|
| 758 | * handling. This function determines the number of bytes which
|
| 759 | * can be failed from the beginning of the request without
|
| 760 | * crossing into area which need to be retried further.
|
| 761 | *
|
| 762 | * Return:
|
| 763 | * The number of bytes to fail.
|
| 764 |
|
| 765 | static unsigned int scsi_rq_err_bytes(const struct request *rq)
|
| 766 | {
|
| 767 | blk_opf_t ff = rq->cmd_flags & REQ_FAILFAST_MASK;
|
| 768 | unsigned int bytes = 0;
|
| 769 | struct bio *bio;
|
| 770 |
|
| 771 | if (!(rq->rq_flags & RQF_MIXED_MERGE))
|
| 772 | return blk_rq_bytes(rq);
|
| 773 |
|
| 774 | |
| 775 | * Currently the only 'mixing' which can happen is between
|
| 776 | * different fastfail types. We can safely fail portions
|
| 777 | * which have all the failfast bits that the first one has -
|
| 778 | * the ones which are at least as eager to fail as the first
|
| 779 | * one.
|
| 780 |
|
| 781 | for (bio = rq->bio; bio; bio = bio->bi_next) {
|
| 782 | if ((bio->bi_opf & ff) != ff)
|
| 783 | break;
|
| 784 | bytes += bio->bi_iter.bi_size;
|
| 785 | }
|
| 786 |
|
| 787 |
|
| 788 | BUG_ON(blk_rq_bytes(rq) && !bytes);
|
| 789 | return bytes;
|
| 790 | }
|
| 791 |
|
| 792 | static bool scsi_cmd_runtime_exceeced(struct scsi_cmnd *cmd)
|
| 793 | {
|
| 794 | struct request *req = scsi_cmd_to_rq(cmd);
|
| 795 | unsigned long wait_for;
|
| 796 |
|
| 797 | if (cmd->allowed == SCSI_CMD_RETRIES_NO_LIMIT)
|
| 798 | return false;
|
| 799 |
|
| 800 | wait_for = (cmd->allowed + 1) * req->timeout;
|
| 801 | if (time_before(cmd->jiffies_at_alloc + wait_for, jiffies)) {
|
| 802 | scmd_printk(KERN_ERR, cmd, "timing out command, waited %lus\n",
|
| 803 | wait_for/HZ);
|
| 804 | return true;
|
| 805 | }
|
| 806 | return false;
|
| 807 | }
|
| 808 |
|
| 809 | |
| 810 | * When ALUA transition state is returned, reprep the cmd to
|
| 811 | * use the ALUA handler's transition timeout. Delay the reprep
|
| 812 | * 1 sec to avoid aggressive retries of the target in that
|
| 813 | * state.
|
| 814 |
|
| 815 | #define ALUA_TRANSITION_REPREP_DELAY 1000
|
| 816 |
|
| 817 |
|
| 818 | static void scsi_io_completion_action(struct scsi_cmnd *cmd, int result)
|
| 819 | {
|
| 820 | struct request *req = scsi_cmd_to_rq(cmd);
|
| 821 | int level = 0;
|
| 822 | enum {ACTION_FAIL, ACTION_REPREP, ACTION_DELAYED_REPREP,
|
| 823 | ACTION_RETRY, ACTION_DELAYED_RETRY} action;
|
| 824 | struct scsi_sense_hdr sshdr;
|
| 825 | bool sense_valid;
|
| 826 | bool sense_current = true;
|
| 827 | blk_status_t blk_stat;
|
| 828 |
|
| 829 | sense_valid = scsi_command_normalize_sense(cmd, &sshdr);
|
| 830 | if (sense_valid)
|
| 831 | sense_current = !scsi_sense_is_deferred(&sshdr);
|
| 832 |
|
| 833 | blk_stat = scsi_result_to_blk_status(result);
|
| 834 |
|
| 835 | if (host_byte(result) == DID_RESET) {
|
| 836 | |
| 837 | * reasons. Just retry the command and see what
|
| 838 | * happens.
|
| 839 |
|
| 840 | action = ACTION_RETRY;
|
| 841 | } else if (sense_valid && sense_current) {
|
| 842 | switch (sshdr.sense_key) {
|
| 843 | case UNIT_ATTENTION:
|
| 844 | if (cmd->device->removable) {
|
| 845 | |
| 846 | * and quietly refuse further access.
|
| 847 |
|
| 848 | cmd->device->changed = 1;
|
| 849 | action = ACTION_FAIL;
|
| 850 | } else {
|
| 851 | |
| 852 | * bus reset. Could not have been a
|
| 853 | * media change, so we just retry the
|
| 854 | * command and see what happens.
|
| 855 |
|
| 856 | action = ACTION_RETRY;
|
| 857 | }
|
| 858 | break;
|
| 859 | case ILLEGAL_REQUEST:
|
| 860 | |
| 861 | * we may have performed an unsupported
|
| 862 | * command. The only thing this should be
|
| 863 | * would be a ten byte read where only a six
|
| 864 | * byte read was supported. Also, on a system
|
| 865 | * where READ CAPACITY failed, we may have
|
| 866 | * read past the end of the disk.
|
| 867 |
|
| 868 | if ((cmd->device->use_10_for_rw &&
|
| 869 | sshdr.asc == 0x20 && sshdr.ascq == 0x00) &&
|
| 870 | (cmd->cmnd[0] == READ_10 ||
|
| 871 | cmd->cmnd[0] == WRITE_10)) {
|
| 872 |
|
| 873 | cmd->device->use_10_for_rw = 0;
|
| 874 | action = ACTION_REPREP;
|
| 875 | } else if (sshdr.asc == 0x10) {
|
| 876 | action = ACTION_FAIL;
|
| 877 | blk_stat = BLK_STS_PROTECTION;
|
| 878 |
|
| 879 | } else if (sshdr.asc == 0x20 || sshdr.asc == 0x24) {
|
| 880 | action = ACTION_FAIL;
|
| 881 | blk_stat = BLK_STS_TARGET;
|
| 882 | } else
|
| 883 | action = ACTION_FAIL;
|
| 884 | break;
|
| 885 | case ABORTED_COMMAND:
|
| 886 | action = ACTION_FAIL;
|
| 887 | if (sshdr.asc == 0x10)
|
| 888 | blk_stat = BLK_STS_PROTECTION;
|
| 889 | break;
|
| 890 | case NOT_READY:
|
| 891 | |
| 892 | * ready, or has a temporary blockage, retry.
|
| 893 |
|
| 894 | if (sshdr.asc == 0x04) {
|
| 895 | switch (sshdr.ascq) {
|
| 896 | case 0x01:
|
| 897 | case 0x04:
|
| 898 | case 0x05:
|
| 899 | case 0x06:
|
| 900 | case 0x07:
|
| 901 | case 0x08:
|
| 902 | case 0x09:
|
| 903 | case 0x11:
|
| 904 | case 0x14:
|
| 905 | case 0x1a:
|
| 906 | case 0x1b:
|
| 907 | case 0x1d:
|
| 908 | action = ACTION_DELAYED_RETRY;
|
| 909 | break;
|
| 910 | case 0x0a:
|
| 911 | action = ACTION_DELAYED_REPREP;
|
| 912 | break;
|
| 913 | |
| 914 | * Depopulation might take many hours,
|
| 915 | * thus it is not worthwhile to retry.
|
| 916 |
|
| 917 | case 0x24:
|
| 918 | case 0x25:
|
| 919 | fallthrough;
|
| 920 | default:
|
| 921 | action = ACTION_FAIL;
|
| 922 | break;
|
| 923 | }
|
| 924 | } else
|
| 925 | action = ACTION_FAIL;
|
| 926 | break;
|
| 927 | case VOLUME_OVERFLOW:
|
| 928 |
|
| 929 | action = ACTION_FAIL;
|
| 930 | break;
|
| 931 | case DATA_PROTECT:
|
| 932 | action = ACTION_FAIL;
|
| 933 | if ((sshdr.asc == 0x0C && sshdr.ascq == 0x12) ||
|
| 934 | (sshdr.asc == 0x55 &&
|
| 935 | (sshdr.ascq == 0x0E || sshdr.ascq == 0x0F))) {
|
| 936 |
|
| 937 | blk_stat = BLK_STS_ZONE_OPEN_RESOURCE;
|
| 938 | }
|
| 939 | break;
|
| 940 | case COMPLETED:
|
| 941 | fallthrough;
|
| 942 | default:
|
| 943 | action = ACTION_FAIL;
|
| 944 | break;
|
| 945 | }
|
| 946 | } else
|
| 947 | action = ACTION_FAIL;
|
| 948 |
|
| 949 | if (action != ACTION_FAIL && scsi_cmd_runtime_exceeced(cmd))
|
| 950 | action = ACTION_FAIL;
|
| 951 |
|
| 952 | switch (action) {
|
| 953 | case ACTION_FAIL:
|
| 954 |
|
| 955 | if (!(req->rq_flags & RQF_QUIET)) {
|
| 956 | static DEFINE_RATELIMIT_STATE(_rs,
|
| 957 | DEFAULT_RATELIMIT_INTERVAL,
|
| 958 | DEFAULT_RATELIMIT_BURST);
|
| 959 |
|
| 960 | if (unlikely(scsi_logging_level))
|
| 961 | level =
|
| 962 | SCSI_LOG_LEVEL(SCSI_LOG_MLCOMPLETE_SHIFT,
|
| 963 | SCSI_LOG_MLCOMPLETE_BITS);
|
| 964 |
|
| 965 | |
| 966 | * if logging is enabled the failure will be printed
|
| 967 | * in scsi_log_completion(), so avoid duplicate messages
|
| 968 |
|
| 969 | if (!level && __ratelimit(&_rs)) {
|
| 970 | scsi_print_result(cmd, NULL, FAILED);
|
| 971 | if (sense_valid)
|
| 972 | scsi_print_sense(cmd);
|
| 973 | scsi_print_command(cmd);
|
| 974 | }
|
| 975 | }
|
| 976 | if (!scsi_end_request(req, blk_stat, scsi_rq_err_bytes(req)))
|
| 977 | return;
|
| 978 | fallthrough;
|
| 979 | case ACTION_REPREP:
|
| 980 | scsi_mq_requeue_cmd(cmd, 0);
|
| 981 | break;
|
| 982 | case ACTION_DELAYED_REPREP:
|
| 983 | scsi_mq_requeue_cmd(cmd, ALUA_TRANSITION_REPREP_DELAY);
|
| 984 | break;
|
| 985 | case ACTION_RETRY:
|
| 986 |
|
| 987 | __scsi_queue_insert(cmd, SCSI_MLQUEUE_EH_RETRY, false);
|
| 988 | break;
|
| 989 | case ACTION_DELAYED_RETRY:
|
| 990 |
|
| 991 | __scsi_queue_insert(cmd, SCSI_MLQUEUE_DEVICE_BUSY, false);
|
| 992 | break;
|
| 993 | }
|
| 994 | }
|
| 995 |
|
| 996 | |
| 997 | * Helper for scsi_io_completion() when cmd->result is non-zero. Returns a
|
| 998 | * new result that may suppress further error checking. Also modifies
|
| 999 | * *blk_statp in some cases.
|
| 1000 |
|
| 1001 | static int scsi_io_completion_nz_result(struct scsi_cmnd *cmd, int result,
|
| 1002 | blk_status_t *blk_statp)
|
| 1003 | {
|
| 1004 | bool sense_valid;
|
| 1005 | bool sense_current = true;
|
| 1006 | struct request *req = scsi_cmd_to_rq(cmd);
|
| 1007 | struct scsi_sense_hdr sshdr;
|
| 1008 |
|
| 1009 | sense_valid = scsi_command_normalize_sense(cmd, &sshdr);
|
| 1010 | if (sense_valid)
|
| 1011 | sense_current = !scsi_sense_is_deferred(&sshdr);
|
| 1012 |
|
| 1013 | if (blk_rq_is_passthrough(req)) {
|
| 1014 | if (sense_valid) {
|
| 1015 | |
| 1016 | * SG_IO wants current and deferred errors
|
| 1017 |
|
| 1018 | cmd->sense_len = min(8 + cmd->sense_buffer[7],
|
| 1019 | SCSI_SENSE_BUFFERSIZE);
|
| 1020 | }
|
| 1021 | if (sense_current)
|
| 1022 | *blk_statp = scsi_result_to_blk_status(result);
|
| 1023 | } else if (blk_rq_bytes(req) == 0 && sense_current) {
|
| 1024 | |
| 1025 | * Flush commands do not transfers any data, and thus cannot use
|
| 1026 | * good_bytes != blk_rq_bytes(req) as the signal for an error.
|
| 1027 | * This sets *blk_statp explicitly for the problem case.
|
| 1028 |
|
| 1029 | *blk_statp = scsi_result_to_blk_status(result);
|
| 1030 | }
|
| 1031 | |
| 1032 | * Recovered errors need reporting, but they're always treated as
|
| 1033 | * success, so fiddle the result code here. For passthrough requests
|
| 1034 | * we already took a copy of the original into sreq->result which
|
| 1035 | * is what gets returned to the user
|
| 1036 |
|
| 1037 | if (sense_valid && (sshdr.sense_key == RECOVERED_ERROR)) {
|
| 1038 | bool do_print = true;
|
| 1039 | |
| 1040 | * if ATA PASS-THROUGH INFORMATION AVAILABLE [0x0, 0x1d]
|
| 1041 | * skip print since caller wants ATA registers. Only occurs
|
| 1042 | * on SCSI ATA PASS_THROUGH commands when CK_COND=1
|
| 1043 |
|
| 1044 | if ((sshdr.asc == 0x0) && (sshdr.ascq == 0x1d))
|
| 1045 | do_print = false;
|
| 1046 | else if (req->rq_flags & RQF_QUIET)
|
| 1047 | do_print = false;
|
| 1048 | if (do_print)
|
| 1049 | scsi_print_sense(cmd);
|
| 1050 | result = 0;
|
| 1051 |
|
| 1052 | *blk_statp = BLK_STS_OK;
|
| 1053 | }
|
| 1054 | |
| 1055 | * Another corner case: the SCSI status byte is non-zero but 'good'.
|
| 1056 | * Example: PRE-FETCH command returns SAM_STAT_CONDITION_MET when
|
| 1057 | * it is able to fit nominated LBs in its cache (and SAM_STAT_GOOD
|
| 1058 | * if it can't fit). Treat SAM_STAT_CONDITION_MET and the related
|
| 1059 | * intermediate statuses (both obsolete in SAM-4) as good.
|
| 1060 |
|
| 1061 | if ((result & 0xff) && scsi_status_is_good(result)) {
|
| 1062 | result = 0;
|
| 1063 | *blk_statp = BLK_STS_OK;
|
| 1064 | }
|
| 1065 | return result;
|
| 1066 | }
|
| 1067 |
|
| 1068 | |
| 1069 | * scsi_io_completion - Completion processing for SCSI commands.
|
| 1070 | * @cmd: command that is finished.
|
| 1071 | * @good_bytes: number of processed bytes.
|
| 1072 | *
|
| 1073 | * We will finish off the specified number of sectors. If we are done, the
|
| 1074 | * command block will be released and the queue function will be goosed. If we
|
| 1075 | * are not done then we have to figure out what to do next:
|
| 1076 | *
|
| 1077 | * a) We can call scsi_mq_requeue_cmd(). The request will be
|
| 1078 | * unprepared and put back on the queue. Then a new command will
|
| 1079 | * be created for it. This should be used if we made forward
|
| 1080 | * progress, or if we want to switch from READ(10) to READ(6) for
|
| 1081 | * example.
|
| 1082 | *
|
| 1083 | * b) We can call scsi_io_completion_action(). The request will be
|
| 1084 | * put back on the queue and retried using the same command as
|
| 1085 | * before, possibly after a delay.
|
| 1086 | *
|
| 1087 | * c) We can call scsi_end_request() with blk_stat other than
|
| 1088 | * BLK_STS_OK, to fail the remainder of the request.
|
| 1089 |
|
| 1090 | void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes)
|
| 1091 | {
|
| 1092 | int result = cmd->result;
|
| 1093 | struct request *req = scsi_cmd_to_rq(cmd);
|
| 1094 | blk_status_t blk_stat = BLK_STS_OK;
|
| 1095 |
|
| 1096 | if (unlikely(result))
|
| 1097 | result = scsi_io_completion_nz_result(cmd, result, &blk_stat);
|
| 1098 |
|
| 1099 | |
| 1100 | * Next deal with any sectors which we were able to correctly
|
| 1101 | * handle.
|
| 1102 |
|
| 1103 | SCSI_LOG_HLCOMPLETE(1, scmd_printk(KERN_INFO, cmd,
|
| 1104 | "%u sectors total, %d bytes done.\n",
|
| 1105 | blk_rq_sectors(req), good_bytes));
|
| 1106 |
|
| 1107 | |
| 1108 | * Failed, zero length commands always need to drop down
|
| 1109 | * to retry code. Fast path should return in this block.
|
| 1110 |
|
| 1111 | if (likely(blk_rq_bytes(req) > 0 || blk_stat == BLK_STS_OK)) {
|
| 1112 | if (likely(!scsi_end_request(req, blk_stat, good_bytes)))
|
| 1113 | return;
|
| 1114 | }
|
| 1115 |
|
| 1116 |
|
| 1117 | if (unlikely(blk_stat && scsi_noretry_cmd(cmd))) {
|
| 1118 | if (scsi_end_request(req, blk_stat, blk_rq_bytes(req)))
|
| 1119 | WARN_ONCE(true,
|
| 1120 | "Bytes remaining after failed, no-retry command");
|
| 1121 | return;
|
| 1122 | }
|
| 1123 |
|
| 1124 | |
| 1125 | * If there had been no error, but we have leftover bytes in the
|
| 1126 | * request just queue the command up again.
|
| 1127 |
|
| 1128 | if (likely(result == 0))
|
| 1129 | scsi_mq_requeue_cmd(cmd, 0);
|
| 1130 | else
|
| 1131 | scsi_io_completion_action(cmd, result);
|
| 1132 | }
|
| 1133 |
|
| 1134 | static inline bool scsi_cmd_needs_dma_drain(struct scsi_device *sdev,
|
| 1135 | struct request *rq)
|
| 1136 | {
|
| 1137 | return sdev->dma_drain_len && blk_rq_is_passthrough(rq) &&
|
| 1138 | !op_is_write(req_op(rq)) &&
|
| 1139 | sdev->host->hostt->dma_need_drain(rq);
|
| 1140 | }
|
| 1141 |
|
| 1142 | |
| 1143 | * scsi_alloc_sgtables - Allocate and initialize data and integrity scatterlists
|
| 1144 | * @cmd: SCSI command data structure to initialize.
|
| 1145 | *
|
| 1146 | * Initializes @cmd->sdb and also @cmd->prot_sdb if data integrity is enabled
|
| 1147 | * for @cmd.
|
| 1148 | *
|
| 1149 | * Returns:
|
| 1150 | * * BLK_STS_OK - on success
|
| 1151 | * * BLK_STS_RESOURCE - if the failure is retryable
|
| 1152 | * * BLK_STS_IOERR - if the failure is fatal
|
| 1153 |
|
| 1154 | blk_status_t scsi_alloc_sgtables(struct scsi_cmnd *cmd)
|
| 1155 | {
|
| 1156 | struct scsi_device *sdev = cmd->device;
|
| 1157 | struct request *rq = scsi_cmd_to_rq(cmd);
|
| 1158 | unsigned short nr_segs = blk_rq_nr_phys_segments(rq);
|
| 1159 | struct scatterlist *last_sg = NULL;
|
| 1160 | blk_status_t ret;
|
| 1161 | bool need_drain = scsi_cmd_needs_dma_drain(sdev, rq);
|
| 1162 | int count;
|
| 1163 |
|
| 1164 | if (WARN_ON_ONCE(!nr_segs))
|
| 1165 | return BLK_STS_IOERR;
|
| 1166 |
|
| 1167 | |
| 1168 | * Make sure there is space for the drain. The driver must adjust
|
| 1169 | * max_hw_segments to be prepared for this.
|
| 1170 |
|
| 1171 | if (need_drain)
|
| 1172 | nr_segs++;
|
| 1173 |
|
| 1174 | |
| 1175 | * If sg table allocation fails, requeue request later.
|
| 1176 |
|
| 1177 | if (unlikely(sg_alloc_table_chained(&cmd->sdb.table, nr_segs,
|
| 1178 | cmd->sdb.table.sgl, SCSI_INLINE_SG_CNT)))
|
| 1179 | return BLK_STS_RESOURCE;
|
| 1180 |
|
| 1181 | |
| 1182 | * Next, walk the list, and fill in the addresses and sizes of
|
| 1183 | * each segment.
|
| 1184 |
|
| 1185 | count = __blk_rq_map_sg(rq, cmd->sdb.table.sgl, &last_sg);
|
| 1186 |
|
| 1187 | if (blk_rq_bytes(rq) & rq->q->limits.dma_pad_mask) {
|
| 1188 | unsigned int pad_len =
|
| 1189 | (rq->q->limits.dma_pad_mask & ~blk_rq_bytes(rq)) + 1;
|
| 1190 | unsigned int data_len = last_sg->length;
|
| 1191 |
|
| 1192 | last_sg->length += pad_len;
|
| 1193 | sg_zero_buffer(last_sg, 1, pad_len, data_len);
|
| 1194 | cmd->extra_len += pad_len;
|
| 1195 | }
|
| 1196 |
|
| 1197 | if (need_drain) {
|
| 1198 | sg_unmark_end(last_sg);
|
| 1199 | last_sg = sg_next(last_sg);
|
| 1200 | sg_set_buf(last_sg, sdev->dma_drain_buf, sdev->dma_drain_len);
|
| 1201 | sg_mark_end(last_sg);
|
| 1202 |
|
| 1203 | cmd->extra_len += sdev->dma_drain_len;
|
| 1204 | count++;
|
| 1205 | }
|
| 1206 |
|
| 1207 | BUG_ON(count > cmd->sdb.table.nents);
|
| 1208 | cmd->sdb.table.nents = count;
|
| 1209 | cmd->sdb.length = blk_rq_payload_bytes(rq);
|
| 1210 |
|
| 1211 | if (blk_integrity_rq(rq)) {
|
| 1212 | struct scsi_data_buffer *prot_sdb = cmd->prot_sdb;
|
| 1213 |
|
| 1214 | if (WARN_ON_ONCE(!prot_sdb)) {
|
| 1215 | |
| 1216 | * This can happen if someone (e.g. multipath)
|
| 1217 | * queues a command to a device on an adapter
|
| 1218 | * that does not support DIX.
|
| 1219 |
|
| 1220 | ret = BLK_STS_IOERR;
|
| 1221 | goto out_free_sgtables;
|
| 1222 | }
|
| 1223 |
|
| 1224 | if (sg_alloc_table_chained(&prot_sdb->table,
|
| 1225 | rq->nr_integrity_segments,
|
| 1226 | prot_sdb->table.sgl,
|
| 1227 | SCSI_INLINE_PROT_SG_CNT)) {
|
| 1228 | ret = BLK_STS_RESOURCE;
|
| 1229 | goto out_free_sgtables;
|
| 1230 | }
|
| 1231 |
|
| 1232 | count = blk_rq_map_integrity_sg(rq, prot_sdb->table.sgl);
|
| 1233 | cmd->prot_sdb = prot_sdb;
|
| 1234 | cmd->prot_sdb->table.nents = count;
|
| 1235 | }
|
| 1236 |
|
| 1237 | return BLK_STS_OK;
|
| 1238 | out_free_sgtables:
|
| 1239 | scsi_free_sgtables(cmd);
|
| 1240 | return ret;
|
| 1241 | }
|
| 1242 | EXPORT_SYMBOL(scsi_alloc_sgtables);
|
| 1243 |
|
| 1244 | |
| 1245 | * scsi_initialize_rq - initialize struct scsi_cmnd partially
|
| 1246 | * @rq: Request associated with the SCSI command to be initialized.
|
| 1247 | *
|
| 1248 | * This function initializes the members of struct scsi_cmnd that must be
|
| 1249 | * initialized before request processing starts and that won't be
|
| 1250 | * reinitialized if a SCSI command is requeued.
|
| 1251 |
|
| 1252 | static void scsi_initialize_rq(struct request *rq)
|
| 1253 | {
|
| 1254 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq);
|
| 1255 |
|
| 1256 | memset(cmd->cmnd, 0, sizeof(cmd->cmnd));
|
| 1257 | cmd->cmd_len = MAX_COMMAND_SIZE;
|
| 1258 | cmd->sense_len = 0;
|
| 1259 | init_rcu_head(&cmd->rcu);
|
| 1260 | cmd->jiffies_at_alloc = jiffies;
|
| 1261 | cmd->retries = 0;
|
| 1262 | }
|
| 1263 |
|
| 1264 | |
| 1265 | * scsi_alloc_request - allocate a block request and partially
|
| 1266 | * initialize its &scsi_cmnd
|
| 1267 | * @q: the device's request queue
|
| 1268 | * @opf: the request operation code
|
| 1269 | * @flags: block layer allocation flags
|
| 1270 | *
|
| 1271 | * Return: &struct request pointer on success or %NULL on failure
|
| 1272 |
|
| 1273 | struct request *scsi_alloc_request(struct request_queue *q, blk_opf_t opf,
|
| 1274 | blk_mq_req_flags_t flags)
|
| 1275 | {
|
| 1276 | struct request *rq;
|
| 1277 |
|
| 1278 | rq = blk_mq_alloc_request(q, opf, flags);
|
| 1279 | if (!IS_ERR(rq))
|
| 1280 | scsi_initialize_rq(rq);
|
| 1281 | return rq;
|
| 1282 | }
|
| 1283 | EXPORT_SYMBOL_GPL(scsi_alloc_request);
|
| 1284 |
|
| 1285 | |
| 1286 | * Only called when the request isn't completed by SCSI, and not freed by
|
| 1287 | * SCSI
|
| 1288 |
|
| 1289 | static void scsi_cleanup_rq(struct request *rq)
|
| 1290 | {
|
| 1291 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq);
|
| 1292 |
|
| 1293 | cmd->flags = 0;
|
| 1294 |
|
| 1295 | if (rq->rq_flags & RQF_DONTPREP) {
|
| 1296 | scsi_mq_uninit_cmd(cmd);
|
| 1297 | rq->rq_flags &= ~RQF_DONTPREP;
|
| 1298 | }
|
| 1299 | }
|
| 1300 |
|
| 1301 |
|
| 1302 | void scsi_init_command(struct scsi_device *dev, struct scsi_cmnd *cmd)
|
| 1303 | {
|
| 1304 | struct request *rq = scsi_cmd_to_rq(cmd);
|
| 1305 |
|
| 1306 | if (!blk_rq_is_passthrough(rq) && !(cmd->flags & SCMD_INITIALIZED)) {
|
| 1307 | cmd->flags |= SCMD_INITIALIZED;
|
| 1308 | scsi_initialize_rq(rq);
|
| 1309 | }
|
| 1310 |
|
| 1311 | cmd->device = dev;
|
| 1312 | INIT_LIST_HEAD(&cmd->eh_entry);
|
| 1313 | INIT_DELAYED_WORK(&cmd->abort_work, scmd_eh_abort_handler);
|
| 1314 | }
|
| 1315 |
|
| 1316 | static blk_status_t scsi_setup_scsi_cmnd(struct scsi_device *sdev,
|
| 1317 | struct request *req)
|
| 1318 | {
|
| 1319 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
|
| 1320 |
|
| 1321 | |
| 1322 | * Passthrough requests may transfer data, in which case they must
|
| 1323 | * a bio attached to them. Or they might contain a SCSI command
|
| 1324 | * that does not transfer data, in which case they may optionally
|
| 1325 | * submit a request without an attached bio.
|
| 1326 |
|
| 1327 | if (req->bio) {
|
| 1328 | blk_status_t ret = scsi_alloc_sgtables(cmd);
|
| 1329 | if (unlikely(ret != BLK_STS_OK))
|
| 1330 | return ret;
|
| 1331 | } else {
|
| 1332 | BUG_ON(blk_rq_bytes(req));
|
| 1333 |
|
| 1334 | memset(&cmd->sdb, 0, sizeof(cmd->sdb));
|
| 1335 | }
|
| 1336 |
|
| 1337 | cmd->transfersize = blk_rq_bytes(req);
|
| 1338 | return BLK_STS_OK;
|
| 1339 | }
|
| 1340 |
|
| 1341 | static blk_status_t
|
| 1342 | scsi_device_state_check(struct scsi_device *sdev, struct request *req)
|
| 1343 | {
|
| 1344 | switch (sdev->sdev_state) {
|
| 1345 | case SDEV_CREATED:
|
| 1346 | return BLK_STS_OK;
|
| 1347 | case SDEV_OFFLINE:
|
| 1348 | case SDEV_TRANSPORT_OFFLINE:
|
| 1349 | |
| 1350 | * If the device is offline we refuse to process any
|
| 1351 | * commands. The device must be brought online
|
| 1352 | * before trying any recovery commands.
|
| 1353 |
|
| 1354 | if (!sdev->offline_already) {
|
| 1355 | sdev->offline_already = true;
|
| 1356 | sdev_printk(KERN_ERR, sdev,
|
| 1357 | "rejecting I/O to offline device\n");
|
| 1358 | }
|
| 1359 | return BLK_STS_IOERR;
|
| 1360 | case SDEV_DEL:
|
| 1361 | |
| 1362 | * If the device is fully deleted, we refuse to
|
| 1363 | * process any commands as well.
|
| 1364 |
|
| 1365 | sdev_printk(KERN_ERR, sdev,
|
| 1366 | "rejecting I/O to dead device\n");
|
| 1367 | return BLK_STS_IOERR;
|
| 1368 | case SDEV_BLOCK:
|
| 1369 | case SDEV_CREATED_BLOCK:
|
| 1370 | return BLK_STS_RESOURCE;
|
| 1371 | case SDEV_QUIESCE:
|
| 1372 | |
| 1373 | * If the device is blocked we only accept power management
|
| 1374 | * commands.
|
| 1375 |
|
| 1376 | if (req && WARN_ON_ONCE(!(req->rq_flags & RQF_PM)))
|
| 1377 | return BLK_STS_RESOURCE;
|
| 1378 | return BLK_STS_OK;
|
| 1379 | default:
|
| 1380 | |
| 1381 | * For any other not fully online state we only allow
|
| 1382 | * power management commands.
|
| 1383 |
|
| 1384 | if (req && !(req->rq_flags & RQF_PM))
|
| 1385 | return BLK_STS_OFFLINE;
|
| 1386 | return BLK_STS_OK;
|
| 1387 | }
|
| 1388 | }
|
| 1389 |
|
| 1390 | |
| 1391 | * scsi_dev_queue_ready: if we can send requests to sdev, assign one token
|
| 1392 | * and return the token else return -1.
|
| 1393 |
|
| 1394 | static inline int scsi_dev_queue_ready(struct request_queue *q,
|
| 1395 | struct scsi_device *sdev)
|
| 1396 | {
|
| 1397 | int token;
|
| 1398 |
|
| 1399 | if (!sdev->budget_map.map)
|
| 1400 | return INT_MAX;
|
| 1401 |
|
| 1402 | token = sbitmap_get(&sdev->budget_map);
|
| 1403 | if (token < 0)
|
| 1404 | return -1;
|
| 1405 |
|
| 1406 | if (!atomic_read(&sdev->device_blocked))
|
| 1407 | return token;
|
| 1408 |
|
| 1409 | |
| 1410 | * Only unblock if no other commands are pending and
|
| 1411 | * if device_blocked has decreased to zero
|
| 1412 |
|
| 1413 | if (scsi_device_busy(sdev) > 1 ||
|
| 1414 | atomic_dec_return(&sdev->device_blocked) > 0) {
|
| 1415 | sbitmap_put(&sdev->budget_map, token);
|
| 1416 | return -1;
|
| 1417 | }
|
| 1418 |
|
| 1419 | SCSI_LOG_MLQUEUE(3, sdev_printk(KERN_INFO, sdev,
|
| 1420 | "unblocking device at zero depth\n"));
|
| 1421 |
|
| 1422 | return token;
|
| 1423 | }
|
| 1424 |
|
| 1425 | |
| 1426 | * scsi_target_queue_ready: checks if there we can send commands to target
|
| 1427 | * @sdev: scsi device on starget to check.
|
| 1428 |
|
| 1429 | static inline int scsi_target_queue_ready(struct Scsi_Host *shost,
|
| 1430 | struct scsi_device *sdev)
|
| 1431 | {
|
| 1432 | struct scsi_target *starget = scsi_target(sdev);
|
| 1433 | unsigned int busy;
|
| 1434 |
|
| 1435 | if (starget->single_lun) {
|
| 1436 | spin_lock_irq(shost->host_lock);
|
| 1437 | if (starget->starget_sdev_user &&
|
| 1438 | starget->starget_sdev_user != sdev) {
|
| 1439 | spin_unlock_irq(shost->host_lock);
|
| 1440 | return 0;
|
| 1441 | }
|
| 1442 | starget->starget_sdev_user = sdev;
|
| 1443 | spin_unlock_irq(shost->host_lock);
|
| 1444 | }
|
| 1445 |
|
| 1446 | if (starget->can_queue <= 0)
|
| 1447 | return 1;
|
| 1448 |
|
| 1449 | busy = atomic_inc_return(&starget->target_busy) - 1;
|
| 1450 | if (atomic_read(&starget->target_blocked) > 0) {
|
| 1451 | if (busy)
|
| 1452 | goto starved;
|
| 1453 |
|
| 1454 | |
| 1455 | * unblock after target_blocked iterates to zero
|
| 1456 |
|
| 1457 | if (atomic_dec_return(&starget->target_blocked) > 0)
|
| 1458 | goto out_dec;
|
| 1459 |
|
| 1460 | SCSI_LOG_MLQUEUE(3, starget_printk(KERN_INFO, starget,
|
| 1461 | "unblocking target at zero depth\n"));
|
| 1462 | }
|
| 1463 |
|
| 1464 | if (busy >= starget->can_queue)
|
| 1465 | goto starved;
|
| 1466 |
|
| 1467 | return 1;
|
| 1468 |
|
| 1469 | starved:
|
| 1470 | spin_lock_irq(shost->host_lock);
|
| 1471 | list_move_tail(&sdev->starved_entry, &shost->starved_list);
|
| 1472 | spin_unlock_irq(shost->host_lock);
|
| 1473 | out_dec:
|
| 1474 | if (starget->can_queue > 0)
|
| 1475 | atomic_dec(&starget->target_busy);
|
| 1476 | return 0;
|
| 1477 | }
|
| 1478 |
|
| 1479 | |
| 1480 | * scsi_host_queue_ready: if we can send requests to shost, return 1 else
|
| 1481 | * return 0. We must end up running the queue again whenever 0 is
|
| 1482 | * returned, else IO can hang.
|
| 1483 |
|
| 1484 | static inline int scsi_host_queue_ready(struct request_queue *q,
|
| 1485 | struct Scsi_Host *shost,
|
| 1486 | struct scsi_device *sdev,
|
| 1487 | struct scsi_cmnd *cmd)
|
| 1488 | {
|
| 1489 | if (atomic_read(&shost->host_blocked) > 0) {
|
| 1490 | if (scsi_host_busy(shost) > 0)
|
| 1491 | goto starved;
|
| 1492 |
|
| 1493 | |
| 1494 | * unblock after host_blocked iterates to zero
|
| 1495 |
|
| 1496 | if (atomic_dec_return(&shost->host_blocked) > 0)
|
| 1497 | goto out_dec;
|
| 1498 |
|
| 1499 | SCSI_LOG_MLQUEUE(3,
|
| 1500 | shost_printk(KERN_INFO, shost,
|
| 1501 | "unblocking host at zero depth\n"));
|
| 1502 | }
|
| 1503 |
|
| 1504 | if (shost->host_self_blocked)
|
| 1505 | goto starved;
|
| 1506 |
|
| 1507 |
|
| 1508 | if (!list_empty(&sdev->starved_entry)) {
|
| 1509 | spin_lock_irq(shost->host_lock);
|
| 1510 | if (!list_empty(&sdev->starved_entry))
|
| 1511 | list_del_init(&sdev->starved_entry);
|
| 1512 | spin_unlock_irq(shost->host_lock);
|
| 1513 | }
|
| 1514 |
|
| 1515 | __set_bit(SCMD_STATE_INFLIGHT, &cmd->state);
|
| 1516 |
|
| 1517 | return 1;
|
| 1518 |
|
| 1519 | starved:
|
| 1520 | spin_lock_irq(shost->host_lock);
|
| 1521 | if (list_empty(&sdev->starved_entry))
|
| 1522 | list_add_tail(&sdev->starved_entry, &shost->starved_list);
|
| 1523 | spin_unlock_irq(shost->host_lock);
|
| 1524 | out_dec:
|
| 1525 | scsi_dec_host_busy(shost, cmd);
|
| 1526 | return 0;
|
| 1527 | }
|
| 1528 |
|
| 1529 | |
| 1530 | * Busy state exporting function for request stacking drivers.
|
| 1531 | *
|
| 1532 | * For efficiency, no lock is taken to check the busy state of
|
| 1533 | * shost/starget/sdev, since the returned value is not guaranteed and
|
| 1534 | * may be changed after request stacking drivers call the function,
|
| 1535 | * regardless of taking lock or not.
|
| 1536 | *
|
| 1537 | * When scsi can't dispatch I/Os anymore and needs to kill I/Os scsi
|
| 1538 | * needs to return 'not busy'. Otherwise, request stacking drivers
|
| 1539 | * may hold requests forever.
|
| 1540 |
|
| 1541 | static bool scsi_mq_lld_busy(struct request_queue *q)
|
| 1542 | {
|
| 1543 | struct scsi_device *sdev = q->queuedata;
|
| 1544 | struct Scsi_Host *shost;
|
| 1545 |
|
| 1546 | if (blk_queue_dying(q))
|
| 1547 | return false;
|
| 1548 |
|
| 1549 | shost = sdev->host;
|
| 1550 |
|
| 1551 | |
| 1552 | * Ignore host/starget busy state.
|
| 1553 | * Since block layer does not have a concept of fairness across
|
| 1554 | * multiple queues, congestion of host/starget needs to be handled
|
| 1555 | * in SCSI layer.
|
| 1556 |
|
| 1557 | if (scsi_host_in_recovery(shost) || scsi_device_is_busy(sdev))
|
| 1558 | return true;
|
| 1559 |
|
| 1560 | return false;
|
| 1561 | }
|
| 1562 |
|
| 1563 | |
| 1564 | * Block layer request completion callback. May be called from interrupt
|
| 1565 | * context.
|
| 1566 |
|
| 1567 | static void scsi_complete(struct request *rq)
|
| 1568 | {
|
| 1569 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq);
|
| 1570 | enum scsi_disposition disposition;
|
| 1571 |
|
| 1572 | if (blk_mq_is_reserved_rq(rq)) {
|
| 1573 |
|
| 1574 | WARN_ON_ONCE(!blk_rq_is_passthrough(scsi_cmd_to_rq(cmd)));
|
| 1575 | scsi_mq_uninit_cmd(cmd);
|
| 1576 | __blk_mq_end_request(rq, scsi_result_to_blk_status(cmd->result));
|
| 1577 | return;
|
| 1578 | }
|
| 1579 |
|
| 1580 | INIT_LIST_HEAD(&cmd->eh_entry);
|
| 1581 |
|
| 1582 | atomic_inc(&cmd->device->iodone_cnt);
|
| 1583 | if (cmd->result)
|
| 1584 | atomic_inc(&cmd->device->ioerr_cnt);
|
| 1585 |
|
| 1586 | disposition = scsi_decide_disposition(cmd);
|
| 1587 | if (disposition != SUCCESS && scsi_cmd_runtime_exceeced(cmd))
|
| 1588 | disposition = SUCCESS;
|
| 1589 |
|
| 1590 | scsi_log_completion(cmd, disposition);
|
| 1591 |
|
| 1592 | switch (disposition) {
|
| 1593 | case SUCCESS:
|
| 1594 | scsi_finish_command(cmd);
|
| 1595 | break;
|
| 1596 | case NEEDS_RETRY:
|
| 1597 | scsi_queue_insert(cmd, SCSI_MLQUEUE_EH_RETRY);
|
| 1598 | break;
|
| 1599 | case ADD_TO_MLQUEUE:
|
| 1600 | scsi_queue_insert(cmd, SCSI_MLQUEUE_DEVICE_BUSY);
|
| 1601 | break;
|
| 1602 | default:
|
| 1603 | scsi_eh_scmd_add(cmd);
|
| 1604 | break;
|
| 1605 | }
|
| 1606 | }
|
| 1607 |
|
| 1608 | |
| 1609 | * scsi_dispatch_cmd - Dispatch a command to the low-level driver.
|
| 1610 | * @cmd: command block we are dispatching.
|
| 1611 | *
|
| 1612 | * Return: nonzero return request was rejected and device's queue needs to be
|
| 1613 | * plugged.
|
| 1614 |
|
| 1615 | static enum scsi_qc_status scsi_dispatch_cmd(struct scsi_cmnd *cmd)
|
| 1616 | {
|
| 1617 | struct Scsi_Host *host = cmd->device->host;
|
| 1618 | int rtn = 0;
|
| 1619 |
|
| 1620 | atomic_inc(&cmd->device->iorequest_cnt);
|
| 1621 |
|
| 1622 |
|
| 1623 | if (unlikely(cmd->device->sdev_state == SDEV_DEL)) {
|
| 1624 | |
| 1625 | * returns an immediate error upwards, and signals
|
| 1626 | * that the device is no longer present
|
| 1627 | cmd->result = DID_NO_CONNECT << 16;
|
| 1628 | goto done;
|
| 1629 | }
|
| 1630 |
|
| 1631 |
|
| 1632 | if (unlikely(scsi_device_blocked(cmd->device))) {
|
| 1633 | |
| 1634 | * in blocked state, the command is just put back on
|
| 1635 | * the device queue. The suspend state has already
|
| 1636 | * blocked the queue so future requests should not
|
| 1637 | * occur until the device transitions out of the
|
| 1638 | * suspend state.
|
| 1639 |
|
| 1640 | SCSI_LOG_MLQUEUE(3, scmd_printk(KERN_INFO, cmd,
|
| 1641 | "queuecommand : device blocked\n"));
|
| 1642 | atomic_dec(&cmd->device->iorequest_cnt);
|
| 1643 | return SCSI_MLQUEUE_DEVICE_BUSY;
|
| 1644 | }
|
| 1645 |
|
| 1646 |
|
| 1647 | if (cmd->device->lun_in_cdb)
|
| 1648 | cmd->cmnd[1] = (cmd->cmnd[1] & 0x1f) |
|
| 1649 | (cmd->device->lun << 5 & 0xe0);
|
| 1650 |
|
| 1651 | scsi_log_send(cmd);
|
| 1652 |
|
| 1653 | |
| 1654 | * Before we queue this command, check if the command
|
| 1655 | * length exceeds what the host adapter can handle.
|
| 1656 |
|
| 1657 | if (cmd->cmd_len > cmd->device->host->max_cmd_len) {
|
| 1658 | SCSI_LOG_MLQUEUE(3, scmd_printk(KERN_INFO, cmd,
|
| 1659 | "queuecommand : command too long. "
|
| 1660 | "cdb_size=%d host->max_cmd_len=%d\n",
|
| 1661 | cmd->cmd_len, cmd->device->host->max_cmd_len));
|
| 1662 | cmd->result = (DID_ABORT << 16);
|
| 1663 | goto done;
|
| 1664 | }
|
| 1665 |
|
| 1666 | if (unlikely(scsi_get_host_state(host) == SHOST_DEL)) {
|
| 1667 | cmd->result = (DID_NO_CONNECT << 16);
|
| 1668 | goto done;
|
| 1669 | }
|
| 1670 |
|
| 1671 | trace_scsi_dispatch_cmd_start(cmd);
|
| 1672 | rtn = host->hostt->queuecommand(host, cmd);
|
| 1673 | if (rtn) {
|
| 1674 | atomic_dec(&cmd->device->iorequest_cnt);
|
| 1675 | trace_scsi_dispatch_cmd_error(cmd, rtn);
|
| 1676 | if (rtn != SCSI_MLQUEUE_DEVICE_BUSY &&
|
| 1677 | rtn != SCSI_MLQUEUE_TARGET_BUSY)
|
| 1678 | rtn = SCSI_MLQUEUE_HOST_BUSY;
|
| 1679 |
|
| 1680 | SCSI_LOG_MLQUEUE(3, scmd_printk(KERN_INFO, cmd,
|
| 1681 | "queuecommand : request rejected\n"));
|
| 1682 | }
|
| 1683 |
|
| 1684 | return rtn;
|
| 1685 | done:
|
| 1686 | scsi_done(cmd);
|
| 1687 | return 0;
|
| 1688 | }
|
| 1689 |
|
| 1690 |
|
| 1691 | static unsigned int scsi_mq_inline_sgl_size(struct Scsi_Host *shost)
|
| 1692 | {
|
| 1693 | return min_t(unsigned int, shost->sg_tablesize, SCSI_INLINE_SG_CNT) *
|
| 1694 | sizeof(struct scatterlist);
|
| 1695 | }
|
| 1696 |
|
| 1697 | static blk_status_t scsi_prepare_cmd(struct request *req)
|
| 1698 | {
|
| 1699 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
|
| 1700 | struct scsi_device *sdev = req->q->queuedata;
|
| 1701 | struct Scsi_Host *shost = sdev->host;
|
| 1702 | bool in_flight = test_bit(SCMD_STATE_INFLIGHT, &cmd->state);
|
| 1703 | struct scatterlist *sg;
|
| 1704 |
|
| 1705 | scsi_init_command(sdev, cmd);
|
| 1706 |
|
| 1707 | cmd->eh_eflags = 0;
|
| 1708 | cmd->prot_type = 0;
|
| 1709 | cmd->prot_flags = 0;
|
| 1710 | cmd->submitter = 0;
|
| 1711 | memset(&cmd->sdb, 0, sizeof(cmd->sdb));
|
| 1712 | cmd->underflow = 0;
|
| 1713 | cmd->transfersize = 0;
|
| 1714 | cmd->host_scribble = NULL;
|
| 1715 | cmd->result = 0;
|
| 1716 | cmd->extra_len = 0;
|
| 1717 | cmd->state = 0;
|
| 1718 | if (in_flight)
|
| 1719 | __set_bit(SCMD_STATE_INFLIGHT, &cmd->state);
|
| 1720 |
|
| 1721 | cmd->prot_op = SCSI_PROT_NORMAL;
|
| 1722 | if (blk_rq_bytes(req))
|
| 1723 | cmd->sc_data_direction = rq_dma_dir(req);
|
| 1724 | else
|
| 1725 | cmd->sc_data_direction = DMA_NONE;
|
| 1726 |
|
| 1727 | sg = (void *)cmd + sizeof(struct scsi_cmnd) + shost->hostt->cmd_size;
|
| 1728 | cmd->sdb.table.sgl = sg;
|
| 1729 |
|
| 1730 | if (scsi_host_get_prot(shost)) {
|
| 1731 | memset(cmd->prot_sdb, 0, sizeof(struct scsi_data_buffer));
|
| 1732 |
|
| 1733 | cmd->prot_sdb->table.sgl =
|
| 1734 | (struct scatterlist *)(cmd->prot_sdb + 1);
|
| 1735 | }
|
| 1736 |
|
| 1737 | |
| 1738 | * Special handling for passthrough commands, which don't go to the ULP
|
| 1739 | * at all:
|
| 1740 |
|
| 1741 | if (blk_rq_is_passthrough(req))
|
| 1742 | return scsi_setup_scsi_cmnd(sdev, req);
|
| 1743 |
|
| 1744 | if (sdev->handler && sdev->handler->prep_fn) {
|
| 1745 | blk_status_t ret = sdev->handler->prep_fn(sdev, req);
|
| 1746 |
|
| 1747 | if (ret != BLK_STS_OK)
|
| 1748 | return ret;
|
| 1749 | }
|
| 1750 |
|
| 1751 |
|
| 1752 | cmd->allowed = 0;
|
| 1753 | memset(cmd->cmnd, 0, sizeof(cmd->cmnd));
|
| 1754 | return scsi_cmd_to_driver(cmd)->init_command(cmd);
|
| 1755 | }
|
| 1756 |
|
| 1757 | static void scsi_done_internal(struct scsi_cmnd *cmd, bool complete_directly)
|
| 1758 | {
|
| 1759 | struct request *req = scsi_cmd_to_rq(cmd);
|
| 1760 |
|
| 1761 | switch (cmd->submitter) {
|
| 1762 | case SUBMITTED_BY_BLOCK_LAYER:
|
| 1763 | break;
|
| 1764 | case SUBMITTED_BY_SCSI_ERROR_HANDLER:
|
| 1765 | return scsi_eh_done(cmd);
|
| 1766 | case SUBMITTED_BY_SCSI_RESET_IOCTL:
|
| 1767 | return;
|
| 1768 | }
|
| 1769 |
|
| 1770 | if (unlikely(blk_should_fake_timeout(scsi_cmd_to_rq(cmd)->q)))
|
| 1771 | return;
|
| 1772 | if (unlikely(test_and_set_bit(SCMD_STATE_COMPLETE, &cmd->state)))
|
| 1773 | return;
|
| 1774 | trace_scsi_dispatch_cmd_done(cmd);
|
| 1775 |
|
| 1776 | if (complete_directly)
|
| 1777 | blk_mq_complete_request_direct(req, scsi_complete);
|
| 1778 | else
|
| 1779 | blk_mq_complete_request(req);
|
| 1780 | }
|
| 1781 |
|
| 1782 | void scsi_done(struct scsi_cmnd *cmd)
|
| 1783 | {
|
| 1784 | scsi_done_internal(cmd, false);
|
| 1785 | }
|
| 1786 | EXPORT_SYMBOL(scsi_done);
|
| 1787 |
|
| 1788 | void scsi_done_direct(struct scsi_cmnd *cmd)
|
| 1789 | {
|
| 1790 | scsi_done_internal(cmd, true);
|
| 1791 | }
|
| 1792 | EXPORT_SYMBOL(scsi_done_direct);
|
| 1793 |
|
| 1794 | static void scsi_mq_put_budget(struct request_queue *q, int budget_token)
|
| 1795 | {
|
| 1796 | struct scsi_device *sdev = q->queuedata;
|
| 1797 |
|
| 1798 | if (sdev->budget_map.map)
|
| 1799 | sbitmap_put(&sdev->budget_map, budget_token);
|
| 1800 | }
|
| 1801 |
|
| 1802 | |
| 1803 | * When to reinvoke queueing after a resource shortage. It's 3 msecs to
|
| 1804 | * not change behaviour from the previous unplug mechanism, experimentation
|
| 1805 | * may prove this needs changing.
|
| 1806 |
|
| 1807 | #define SCSI_QUEUE_DELAY 3
|
| 1808 |
|
| 1809 | static int scsi_mq_get_budget(struct request_queue *q)
|
| 1810 | {
|
| 1811 | struct scsi_device *sdev = q->queuedata;
|
| 1812 | int token = scsi_dev_queue_ready(q, sdev);
|
| 1813 |
|
| 1814 | if (token >= 0)
|
| 1815 | return token;
|
| 1816 |
|
| 1817 | atomic_inc(&sdev->restarts);
|
| 1818 |
|
| 1819 | |
| 1820 | * Orders atomic_inc(&sdev->restarts) and atomic_read(&sdev->device_busy).
|
| 1821 | * .restarts must be incremented before .device_busy is read because the
|
| 1822 | * code in scsi_run_queue_async() depends on the order of these operations.
|
| 1823 |
|
| 1824 | smp_mb__after_atomic();
|
| 1825 |
|
| 1826 | |
| 1827 | * If all in-flight requests originated from this LUN are completed
|
| 1828 | * before reading .device_busy, sdev->device_busy will be observed as
|
| 1829 | * zero, then blk_mq_delay_run_hw_queues() will dispatch this request
|
| 1830 | * soon. Otherwise, completion of one of these requests will observe
|
| 1831 | * the .restarts flag, and the request queue will be run for handling
|
| 1832 | * this request, see scsi_end_request().
|
| 1833 |
|
| 1834 | if (unlikely(scsi_device_busy(sdev) == 0 &&
|
| 1835 | !scsi_device_blocked(sdev)))
|
| 1836 | blk_mq_delay_run_hw_queues(sdev->request_queue, SCSI_QUEUE_DELAY);
|
| 1837 | return -1;
|
| 1838 | }
|
| 1839 |
|
| 1840 | static void scsi_mq_set_rq_budget_token(struct request *req, int token)
|
| 1841 | {
|
| 1842 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
|
| 1843 |
|
| 1844 | cmd->budget_token = token;
|
| 1845 | }
|
| 1846 |
|
| 1847 | static int scsi_mq_get_rq_budget_token(struct request *req)
|
| 1848 | {
|
| 1849 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
|
| 1850 |
|
| 1851 | return cmd->budget_token;
|
| 1852 | }
|
| 1853 |
|
| 1854 | static blk_status_t scsi_queue_rq(struct blk_mq_hw_ctx *hctx,
|
| 1855 | const struct blk_mq_queue_data *bd)
|
| 1856 | {
|
| 1857 | struct request *req = bd->rq;
|
| 1858 | struct request_queue *q = req->q;
|
| 1859 | struct scsi_device *sdev = q->queuedata;
|
| 1860 | struct Scsi_Host *shost = sdev->host;
|
| 1861 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
|
| 1862 | blk_status_t ret;
|
| 1863 | enum scsi_qc_status reason;
|
| 1864 |
|
| 1865 | WARN_ON_ONCE(cmd->budget_token < 0);
|
| 1866 |
|
| 1867 | |
| 1868 | * Bypass the SCSI device, SCSI target and SCSI host checks for
|
| 1869 | * reserved commands.
|
| 1870 |
|
| 1871 | if (!blk_mq_is_reserved_rq(req)) {
|
| 1872 | |
| 1873 | * If the device is not in running state we will reject some or
|
| 1874 | * all commands.
|
| 1875 |
|
| 1876 | if (unlikely(sdev->sdev_state != SDEV_RUNNING)) {
|
| 1877 | ret = scsi_device_state_check(sdev, req);
|
| 1878 | if (ret != BLK_STS_OK)
|
| 1879 | goto out_put_budget;
|
| 1880 | }
|
| 1881 |
|
| 1882 | ret = BLK_STS_RESOURCE;
|
| 1883 | if (!scsi_target_queue_ready(shost, sdev))
|
| 1884 | goto out_put_budget;
|
| 1885 | if (unlikely(scsi_host_in_recovery(shost))) {
|
| 1886 | if (cmd->flags & SCMD_FAIL_IF_RECOVERING)
|
| 1887 | ret = BLK_STS_OFFLINE;
|
| 1888 | goto out_dec_target_busy;
|
| 1889 | }
|
| 1890 | if (!scsi_host_queue_ready(q, shost, sdev, cmd))
|
| 1891 | goto out_dec_target_busy;
|
| 1892 | }
|
| 1893 |
|
| 1894 | |
| 1895 | * Only clear the driver-private command data if the LLD does not supply
|
| 1896 | * a function to initialize that data.
|
| 1897 |
|
| 1898 | if (shost->hostt->cmd_size && !shost->hostt->init_cmd_priv)
|
| 1899 | memset(scsi_cmd_priv(cmd), 0, shost->hostt->cmd_size);
|
| 1900 |
|
| 1901 | if (!(req->rq_flags & RQF_DONTPREP)) {
|
| 1902 | ret = scsi_prepare_cmd(req);
|
| 1903 | if (ret != BLK_STS_OK)
|
| 1904 | goto out_dec_host_busy;
|
| 1905 | req->rq_flags |= RQF_DONTPREP;
|
| 1906 | } else {
|
| 1907 | clear_bit(SCMD_STATE_COMPLETE, &cmd->state);
|
| 1908 | }
|
| 1909 |
|
| 1910 | cmd->flags &= SCMD_PRESERVED_FLAGS;
|
| 1911 | if (sdev->simple_tags)
|
| 1912 | cmd->flags |= SCMD_TAGGED;
|
| 1913 | if (bd->last)
|
| 1914 | cmd->flags |= SCMD_LAST;
|
| 1915 |
|
| 1916 | scsi_set_resid(cmd, 0);
|
| 1917 | memset(cmd->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
|
| 1918 | cmd->submitter = SUBMITTED_BY_BLOCK_LAYER;
|
| 1919 |
|
| 1920 | blk_mq_start_request(req);
|
| 1921 | if (blk_mq_is_reserved_rq(req)) {
|
| 1922 | reason = shost->hostt->queue_reserved_command(shost, cmd);
|
| 1923 | if (reason) {
|
| 1924 | ret = BLK_STS_RESOURCE;
|
| 1925 | goto out_put_budget;
|
| 1926 | }
|
| 1927 | return BLK_STS_OK;
|
| 1928 | }
|
| 1929 | reason = scsi_dispatch_cmd(cmd);
|
| 1930 | if (reason) {
|
| 1931 | scsi_set_blocked(cmd, reason);
|
| 1932 | ret = BLK_STS_RESOURCE;
|
| 1933 | goto out_dec_host_busy;
|
| 1934 | }
|
| 1935 |
|
| 1936 | return BLK_STS_OK;
|
| 1937 |
|
| 1938 | out_dec_host_busy:
|
| 1939 | scsi_dec_host_busy(shost, cmd);
|
| 1940 | out_dec_target_busy:
|
| 1941 | if (scsi_target(sdev)->can_queue > 0)
|
| 1942 | atomic_dec(&scsi_target(sdev)->target_busy);
|
| 1943 | out_put_budget:
|
| 1944 | scsi_mq_put_budget(q, cmd->budget_token);
|
| 1945 | cmd->budget_token = -1;
|
| 1946 | switch (ret) {
|
| 1947 | case BLK_STS_OK:
|
| 1948 | break;
|
| 1949 | case BLK_STS_RESOURCE:
|
| 1950 | if (scsi_device_blocked(sdev))
|
| 1951 | ret = BLK_STS_DEV_RESOURCE;
|
| 1952 | break;
|
| 1953 | case BLK_STS_AGAIN:
|
| 1954 | cmd->result = DID_BUS_BUSY << 16;
|
| 1955 | if (req->rq_flags & RQF_DONTPREP)
|
| 1956 | scsi_mq_uninit_cmd(cmd);
|
| 1957 | break;
|
| 1958 | default:
|
| 1959 | if (unlikely(!scsi_device_online(sdev)))
|
| 1960 | cmd->result = DID_NO_CONNECT << 16;
|
| 1961 | else
|
| 1962 | cmd->result = DID_ERROR << 16;
|
| 1963 | |
| 1964 | * Make sure to release all allocated resources when
|
| 1965 | * we hit an error, as we will never see this command
|
| 1966 | * again.
|
| 1967 |
|
| 1968 | if (req->rq_flags & RQF_DONTPREP)
|
| 1969 | scsi_mq_uninit_cmd(cmd);
|
| 1970 | scsi_run_queue_async(sdev);
|
| 1971 | break;
|
| 1972 | }
|
| 1973 | return ret;
|
| 1974 | }
|
| 1975 |
|
| 1976 | static int scsi_mq_init_request(struct blk_mq_tag_set *set, struct request *rq,
|
| 1977 | unsigned int hctx_idx, int numa_node)
|
| 1978 | {
|
| 1979 | struct Scsi_Host *shost = set->driver_data;
|
| 1980 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq);
|
| 1981 | struct scatterlist *sg;
|
| 1982 | int ret = 0;
|
| 1983 |
|
| 1984 | cmd->sense_buffer =
|
| 1985 | kmem_cache_alloc_node(scsi_sense_cache, GFP_KERNEL, numa_node);
|
| 1986 | if (!cmd->sense_buffer)
|
| 1987 | return -ENOMEM;
|
| 1988 |
|
| 1989 | if (scsi_host_get_prot(shost)) {
|
| 1990 | sg = (void *)cmd + sizeof(struct scsi_cmnd) +
|
| 1991 | shost->hostt->cmd_size;
|
| 1992 | cmd->prot_sdb = (void *)sg + scsi_mq_inline_sgl_size(shost);
|
| 1993 | }
|
| 1994 |
|
| 1995 | if (shost->hostt->init_cmd_priv) {
|
| 1996 | ret = shost->hostt->init_cmd_priv(shost, cmd);
|
| 1997 | if (ret < 0)
|
| 1998 | kmem_cache_free(scsi_sense_cache, cmd->sense_buffer);
|
| 1999 | }
|
| 2000 |
|
| 2001 | return ret;
|
| 2002 | }
|
| 2003 |
|
| 2004 | static void scsi_mq_exit_request(struct blk_mq_tag_set *set, struct request *rq,
|
| 2005 | unsigned int hctx_idx)
|
| 2006 | {
|
| 2007 | struct Scsi_Host *shost = set->driver_data;
|
| 2008 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq);
|
| 2009 |
|
| 2010 | if (shost->hostt->exit_cmd_priv)
|
| 2011 | shost->hostt->exit_cmd_priv(shost, cmd);
|
| 2012 | kmem_cache_free(scsi_sense_cache, cmd->sense_buffer);
|
| 2013 | }
|
| 2014 |
|
| 2015 |
|
| 2016 | static int scsi_mq_poll(struct blk_mq_hw_ctx *hctx, struct io_comp_batch *iob)
|
| 2017 | {
|
| 2018 | struct Scsi_Host *shost = hctx->driver_data;
|
| 2019 |
|
| 2020 | if (shost->hostt->mq_poll)
|
| 2021 | return shost->hostt->mq_poll(shost, hctx->queue_num);
|
| 2022 |
|
| 2023 | return 0;
|
| 2024 | }
|
| 2025 |
|
| 2026 | static int scsi_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
|
| 2027 | unsigned int hctx_idx)
|
| 2028 | {
|
| 2029 | struct Scsi_Host *shost = data;
|
| 2030 |
|
| 2031 | hctx->driver_data = shost;
|
| 2032 | return 0;
|
| 2033 | }
|
| 2034 |
|
| 2035 | static void scsi_map_queues(struct blk_mq_tag_set *set)
|
| 2036 | {
|
| 2037 | struct Scsi_Host *shost = container_of(set, struct Scsi_Host, tag_set);
|
| 2038 |
|
| 2039 | if (shost->hostt->map_queues)
|
| 2040 | return shost->hostt->map_queues(shost);
|
| 2041 | blk_mq_map_queues(&set->map[HCTX_TYPE_DEFAULT]);
|
| 2042 | }
|
| 2043 |
|
| 2044 | void scsi_init_limits(struct Scsi_Host *shost, struct queue_limits *lim)
|
| 2045 | {
|
| 2046 | struct device *dev = shost->dma_dev;
|
| 2047 |
|
| 2048 | memset(lim, 0, sizeof(*lim));
|
| 2049 | lim->max_segments =
|
| 2050 | min_t(unsigned short, shost->sg_tablesize, SG_MAX_SEGMENTS);
|
| 2051 |
|
| 2052 | if (scsi_host_prot_dma(shost)) {
|
| 2053 | shost->sg_prot_tablesize =
|
| 2054 | min_not_zero(shost->sg_prot_tablesize,
|
| 2055 | (unsigned short)SCSI_MAX_PROT_SG_SEGMENTS);
|
| 2056 | BUG_ON(shost->sg_prot_tablesize < shost->sg_tablesize);
|
| 2057 | lim->max_integrity_segments = shost->sg_prot_tablesize;
|
| 2058 | }
|
| 2059 |
|
| 2060 | lim->max_hw_sectors = shost->max_sectors;
|
| 2061 | lim->seg_boundary_mask = shost->dma_boundary;
|
| 2062 | lim->max_segment_size = shost->max_segment_size;
|
| 2063 | lim->virt_boundary_mask = shost->virt_boundary_mask;
|
| 2064 | lim->dma_alignment = max_t(unsigned int,
|
| 2065 | shost->dma_alignment, dma_get_cache_alignment() - 1);
|
| 2066 |
|
| 2067 | |
| 2068 | * Propagate the DMA formation properties to the dma-mapping layer as
|
| 2069 | * a courtesy service to the LLDDs. This needs to check that the buses
|
| 2070 | * actually support the DMA API first, though.
|
| 2071 |
|
| 2072 | if (dev->dma_parms) {
|
| 2073 | dma_set_seg_boundary(dev, shost->dma_boundary);
|
| 2074 | dma_set_max_seg_size(dev, shost->max_segment_size);
|
| 2075 | }
|
| 2076 | }
|
| 2077 | EXPORT_SYMBOL_GPL(scsi_init_limits);
|
| 2078 |
|
| 2079 | static const struct blk_mq_ops scsi_mq_ops_no_commit = {
|
| 2080 | .get_budget = scsi_mq_get_budget,
|
| 2081 | .put_budget = scsi_mq_put_budget,
|
| 2082 | .queue_rq = scsi_queue_rq,
|
| 2083 | .complete = scsi_complete,
|
| 2084 | .timeout = scsi_timeout,
|
| 2085 | #ifdef CONFIG_BLK_DEBUG_FS
|
| 2086 | .show_rq = scsi_show_rq,
|
| 2087 | #endif
|
| 2088 | .init_request = scsi_mq_init_request,
|
| 2089 | .exit_request = scsi_mq_exit_request,
|
| 2090 | .cleanup_rq = scsi_cleanup_rq,
|
| 2091 | .busy = scsi_mq_lld_busy,
|
| 2092 | .map_queues = scsi_map_queues,
|
| 2093 | .init_hctx = scsi_init_hctx,
|
| 2094 | .poll = scsi_mq_poll,
|
| 2095 | .set_rq_budget_token = scsi_mq_set_rq_budget_token,
|
| 2096 | .get_rq_budget_token = scsi_mq_get_rq_budget_token,
|
| 2097 | };
|
| 2098 |
|
| 2099 |
|
| 2100 | static void scsi_commit_rqs(struct blk_mq_hw_ctx *hctx)
|
| 2101 | {
|
| 2102 | struct Scsi_Host *shost = hctx->driver_data;
|
| 2103 |
|
| 2104 | shost->hostt->commit_rqs(shost, hctx->queue_num);
|
| 2105 | }
|
| 2106 |
|
| 2107 | static const struct blk_mq_ops scsi_mq_ops = {
|
| 2108 | .get_budget = scsi_mq_get_budget,
|
| 2109 | .put_budget = scsi_mq_put_budget,
|
| 2110 | .queue_rq = scsi_queue_rq,
|
| 2111 | .commit_rqs = scsi_commit_rqs,
|
| 2112 | .complete = scsi_complete,
|
| 2113 | .timeout = scsi_timeout,
|
| 2114 | #ifdef CONFIG_BLK_DEBUG_FS
|
| 2115 | .show_rq = scsi_show_rq,
|
| 2116 | #endif
|
| 2117 | .init_request = scsi_mq_init_request,
|
| 2118 | .exit_request = scsi_mq_exit_request,
|
| 2119 | .cleanup_rq = scsi_cleanup_rq,
|
| 2120 | .busy = scsi_mq_lld_busy,
|
| 2121 | .map_queues = scsi_map_queues,
|
| 2122 | .init_hctx = scsi_init_hctx,
|
| 2123 | .poll = scsi_mq_poll,
|
| 2124 | .set_rq_budget_token = scsi_mq_set_rq_budget_token,
|
| 2125 | .get_rq_budget_token = scsi_mq_get_rq_budget_token,
|
| 2126 | };
|
| 2127 |
|
| 2128 | int scsi_mq_setup_tags(struct Scsi_Host *shost)
|
| 2129 | {
|
| 2130 | unsigned int cmd_size, sgl_size;
|
| 2131 | struct blk_mq_tag_set *tag_set = &shost->tag_set;
|
| 2132 |
|
| 2133 | sgl_size = max_t(unsigned int, sizeof(struct scatterlist),
|
| 2134 | scsi_mq_inline_sgl_size(shost));
|
| 2135 | cmd_size = sizeof(struct scsi_cmnd) + shost->hostt->cmd_size + sgl_size;
|
| 2136 | if (scsi_host_get_prot(shost))
|
| 2137 | cmd_size += sizeof(struct scsi_data_buffer) +
|
| 2138 | sizeof(struct scatterlist) * SCSI_INLINE_PROT_SG_CNT;
|
| 2139 |
|
| 2140 | memset(tag_set, 0, sizeof(*tag_set));
|
| 2141 | if (shost->hostt->commit_rqs)
|
| 2142 | tag_set->ops = &scsi_mq_ops;
|
| 2143 | else
|
| 2144 | tag_set->ops = &scsi_mq_ops_no_commit;
|
| 2145 | tag_set->nr_hw_queues = shost->nr_hw_queues ? : 1;
|
| 2146 | tag_set->nr_maps = shost->nr_maps ? : 1;
|
| 2147 | tag_set->queue_depth = shost->can_queue + shost->nr_reserved_cmds;
|
| 2148 | tag_set->reserved_tags = shost->nr_reserved_cmds;
|
| 2149 | tag_set->cmd_size = cmd_size;
|
| 2150 | tag_set->numa_node = dev_to_node(shost->dma_dev);
|
| 2151 | if (shost->hostt->tag_alloc_policy_rr)
|
| 2152 | tag_set->flags |= BLK_MQ_F_TAG_RR;
|
| 2153 | if (shost->queuecommand_may_block)
|
| 2154 | tag_set->flags |= BLK_MQ_F_BLOCKING;
|
| 2155 | tag_set->driver_data = shost;
|
| 2156 | if (shost->host_tagset)
|
| 2157 | tag_set->flags |= BLK_MQ_F_TAG_HCTX_SHARED;
|
| 2158 |
|
| 2159 | return blk_mq_alloc_tag_set(tag_set);
|
| 2160 | }
|
| 2161 |
|
| 2162 | void scsi_mq_free_tags(struct kref *kref)
|
| 2163 | {
|
| 2164 | struct Scsi_Host *shost = container_of(kref, typeof(*shost),
|
| 2165 | tagset_refcnt);
|
| 2166 |
|
| 2167 | blk_mq_free_tag_set(&shost->tag_set);
|
| 2168 | complete(&shost->tagset_freed);
|
| 2169 | }
|
| 2170 |
|
| 2171 | |
| 2172 | * scsi_get_internal_cmd() - Allocate an internal SCSI command.
|
| 2173 | * @sdev: SCSI device from which to allocate the command
|
| 2174 | * @data_direction: Data direction for the allocated command
|
| 2175 | * @flags: request allocation flags, e.g. BLK_MQ_REQ_RESERVED or
|
| 2176 | * BLK_MQ_REQ_NOWAIT.
|
| 2177 | *
|
| 2178 | * Allocates a SCSI command for internal LLDD use.
|
| 2179 |
|
| 2180 | struct scsi_cmnd *scsi_get_internal_cmd(struct scsi_device *sdev,
|
| 2181 | enum dma_data_direction data_direction,
|
| 2182 | blk_mq_req_flags_t flags)
|
| 2183 | {
|
| 2184 | enum req_op op = data_direction == DMA_TO_DEVICE ? REQ_OP_DRV_OUT :
|
| 2185 | REQ_OP_DRV_IN;
|
| 2186 | struct scsi_cmnd *scmd;
|
| 2187 | struct request *rq;
|
| 2188 |
|
| 2189 | rq = scsi_alloc_request(sdev->request_queue, op, flags);
|
| 2190 | if (IS_ERR(rq))
|
| 2191 | return NULL;
|
| 2192 | scmd = blk_mq_rq_to_pdu(rq);
|
| 2193 | scmd->device = sdev;
|
| 2194 |
|
| 2195 | return scmd;
|
| 2196 | }
|
| 2197 | EXPORT_SYMBOL_GPL(scsi_get_internal_cmd);
|
| 2198 |
|
| 2199 | |
| 2200 | * scsi_put_internal_cmd() - Free an internal SCSI command.
|
| 2201 | * @scmd: SCSI command to be freed
|
| 2202 |
|
| 2203 | void scsi_put_internal_cmd(struct scsi_cmnd *scmd)
|
| 2204 | {
|
| 2205 | blk_mq_free_request(blk_mq_rq_from_pdu(scmd));
|
| 2206 | }
|
| 2207 | EXPORT_SYMBOL_GPL(scsi_put_internal_cmd);
|
| 2208 |
|
| 2209 | |
| 2210 | * scsi_device_from_queue - return sdev associated with a request_queue
|
| 2211 | * @q: The request queue to return the sdev from
|
| 2212 | *
|
| 2213 | * Return the sdev associated with a request queue or NULL if the
|
| 2214 | * request_queue does not reference a SCSI device.
|
| 2215 |
|
| 2216 | struct scsi_device *scsi_device_from_queue(struct request_queue *q)
|
| 2217 | {
|
| 2218 | struct scsi_device *sdev = NULL;
|
| 2219 |
|
| 2220 | if (q->mq_ops == &scsi_mq_ops_no_commit ||
|
| 2221 | q->mq_ops == &scsi_mq_ops)
|
| 2222 | sdev = q->queuedata;
|
| 2223 | if (!sdev || !get_device(&sdev->sdev_gendev))
|
| 2224 | sdev = NULL;
|
| 2225 |
|
| 2226 | return sdev;
|
| 2227 | }
|
| 2228 |
|
| 2229 | |
| 2230 | * scsi_block_requests - Utility function used by low-level drivers to prevent
|
| 2231 | * further commands from being queued to the device.
|
| 2232 | * @shost: host in question
|
| 2233 | *
|
| 2234 | * There is no timer nor any other means by which the requests get unblocked
|
| 2235 | * other than the low-level driver calling scsi_unblock_requests().
|
| 2236 |
|
| 2237 | void scsi_block_requests(struct Scsi_Host *shost)
|
| 2238 | {
|
| 2239 | shost->host_self_blocked = 1;
|
| 2240 | }
|
| 2241 | EXPORT_SYMBOL(scsi_block_requests);
|
| 2242 |
|
| 2243 | |
| 2244 | * scsi_unblock_requests - Utility function used by low-level drivers to allow
|
| 2245 | * further commands to be queued to the device.
|
| 2246 | * @shost: host in question
|
| 2247 | *
|
| 2248 | * There is no timer nor any other means by which the requests get unblocked
|
| 2249 | * other than the low-level driver calling scsi_unblock_requests(). This is done
|
| 2250 | * as an API function so that changes to the internals of the scsi mid-layer
|
| 2251 | * won't require wholesale changes to drivers that use this feature.
|
| 2252 |
|
| 2253 | void scsi_unblock_requests(struct Scsi_Host *shost)
|
| 2254 | {
|
| 2255 | shost->host_self_blocked = 0;
|
| 2256 | scsi_run_host_queues(shost);
|
| 2257 | }
|
| 2258 | EXPORT_SYMBOL(scsi_unblock_requests);
|
| 2259 |
|
| 2260 | void scsi_exit_queue(void)
|
| 2261 | {
|
| 2262 | kmem_cache_destroy(scsi_sense_cache);
|
| 2263 | }
|
| 2264 |
|
| 2265 | |
| 2266 | * scsi_mode_select - issue a mode select
|
| 2267 | * @sdev: SCSI device to be queried
|
| 2268 | * @pf: Page format bit (1 == standard, 0 == vendor specific)
|
| 2269 | * @sp: Save page bit (0 == don't save, 1 == save)
|
| 2270 | * @buffer: request buffer (may not be smaller than eight bytes)
|
| 2271 | * @len: length of request buffer.
|
| 2272 | * @timeout: command timeout
|
| 2273 | * @retries: number of retries before failing
|
| 2274 | * @data: returns a structure abstracting the mode header data
|
| 2275 | * @sshdr: place to put sense data (or NULL if no sense to be collected).
|
| 2276 | * must be SCSI_SENSE_BUFFERSIZE big.
|
| 2277 | *
|
| 2278 | * Returns zero if successful; negative error number or scsi
|
| 2279 | * status on error
|
| 2280 | *
|
| 2281 |
|
| 2282 | int scsi_mode_select(struct scsi_device *sdev, int pf, int sp,
|
| 2283 | unsigned char *buffer, int len, int timeout, int retries,
|
| 2284 | struct scsi_mode_data *data, struct scsi_sense_hdr *sshdr)
|
| 2285 | {
|
| 2286 | unsigned char cmd[10];
|
| 2287 | unsigned char *real_buffer;
|
| 2288 | const struct scsi_exec_args exec_args = {
|
| 2289 | .sshdr = sshdr,
|
| 2290 | };
|
| 2291 | int ret;
|
| 2292 |
|
| 2293 | memset(cmd, 0, sizeof(cmd));
|
| 2294 | cmd[1] = (pf ? 0x10 : 0) | (sp ? 0x01 : 0);
|
| 2295 |
|
| 2296 | |
| 2297 | * Use MODE SELECT(10) if the device asked for it or if the mode page
|
| 2298 | * and the mode select header cannot fit within the maximumm 255 bytes
|
| 2299 | * of the MODE SELECT(6) command.
|
| 2300 |
|
| 2301 | if (sdev->use_10_for_ms ||
|
| 2302 | len + 4 > 255 ||
|
| 2303 | data->block_descriptor_length > 255) {
|
| 2304 | if (len > 65535 - 8)
|
| 2305 | return -EINVAL;
|
| 2306 | real_buffer = kmalloc(8 + len, GFP_KERNEL);
|
| 2307 | if (!real_buffer)
|
| 2308 | return -ENOMEM;
|
| 2309 | memcpy(real_buffer + 8, buffer, len);
|
| 2310 | len += 8;
|
| 2311 | real_buffer[0] = 0;
|
| 2312 | real_buffer[1] = 0;
|
| 2313 | real_buffer[2] = data->medium_type;
|
| 2314 | real_buffer[3] = data->device_specific;
|
| 2315 | real_buffer[4] = data->longlba ? 0x01 : 0;
|
| 2316 | real_buffer[5] = 0;
|
| 2317 | put_unaligned_be16(data->block_descriptor_length,
|
| 2318 | &real_buffer[6]);
|
| 2319 |
|
| 2320 | cmd[0] = MODE_SELECT_10;
|
| 2321 | put_unaligned_be16(len, &cmd[7]);
|
| 2322 | } else {
|
| 2323 | if (data->longlba)
|
| 2324 | return -EINVAL;
|
| 2325 |
|
| 2326 | real_buffer = kmalloc(4 + len, GFP_KERNEL);
|
| 2327 | if (!real_buffer)
|
| 2328 | return -ENOMEM;
|
| 2329 | memcpy(real_buffer + 4, buffer, len);
|
| 2330 | len += 4;
|
| 2331 | real_buffer[0] = 0;
|
| 2332 | real_buffer[1] = data->medium_type;
|
| 2333 | real_buffer[2] = data->device_specific;
|
| 2334 | real_buffer[3] = data->block_descriptor_length;
|
| 2335 |
|
| 2336 | cmd[0] = MODE_SELECT;
|
| 2337 | cmd[4] = len;
|
| 2338 | }
|
| 2339 |
|
| 2340 | ret = scsi_execute_cmd(sdev, cmd, REQ_OP_DRV_OUT, real_buffer, len,
|
| 2341 | timeout, retries, &exec_args);
|
| 2342 | kfree(real_buffer);
|
| 2343 | return ret;
|
| 2344 | }
|
| 2345 | EXPORT_SYMBOL_GPL(scsi_mode_select);
|
| 2346 |
|
| 2347 | |
| 2348 | * scsi_mode_sense - issue a mode sense, falling back from 10 to six bytes if necessary.
|
| 2349 | * @sdev: SCSI device to be queried
|
| 2350 | * @dbd: set to prevent mode sense from returning block descriptors
|
| 2351 | * @modepage: mode page being requested
|
| 2352 | * @subpage: sub-page of the mode page being requested
|
| 2353 | * @buffer: request buffer (may not be smaller than eight bytes)
|
| 2354 | * @len: length of request buffer.
|
| 2355 | * @timeout: command timeout
|
| 2356 | * @retries: number of retries before failing
|
| 2357 | * @data: returns a structure abstracting the mode header data
|
| 2358 | * @sshdr: place to put sense data (or NULL if no sense to be collected).
|
| 2359 | * must be SCSI_SENSE_BUFFERSIZE big.
|
| 2360 | *
|
| 2361 | * Returns zero if successful, or a negative error number on failure
|
| 2362 |
|
| 2363 | int
|
| 2364 | scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage, int subpage,
|
| 2365 | unsigned char *buffer, int len, int timeout, int retries,
|
| 2366 | struct scsi_mode_data *data, struct scsi_sense_hdr *sshdr)
|
| 2367 | {
|
| 2368 | unsigned char cmd[12];
|
| 2369 | int use_10_for_ms;
|
| 2370 | int header_length;
|
| 2371 | int result;
|
| 2372 | struct scsi_sense_hdr my_sshdr;
|
| 2373 | struct scsi_failure failure_defs[] = {
|
| 2374 | {
|
| 2375 | .sense = UNIT_ATTENTION,
|
| 2376 | .asc = SCMD_FAILURE_ASC_ANY,
|
| 2377 | .ascq = SCMD_FAILURE_ASCQ_ANY,
|
| 2378 | .allowed = retries,
|
| 2379 | .result = SAM_STAT_CHECK_CONDITION,
|
| 2380 | },
|
| 2381 | {}
|
| 2382 | };
|
| 2383 | struct scsi_failures failures = {
|
| 2384 | .failure_definitions = failure_defs,
|
| 2385 | };
|
| 2386 | const struct scsi_exec_args exec_args = {
|
| 2387 |
|
| 2388 | .sshdr = sshdr ? : &my_sshdr,
|
| 2389 | .failures = &failures,
|
| 2390 | };
|
| 2391 |
|
| 2392 | memset(data, 0, sizeof(*data));
|
| 2393 | memset(&cmd[0], 0, 12);
|
| 2394 |
|
| 2395 | dbd = sdev->set_dbd_for_ms ? 8 : dbd;
|
| 2396 | cmd[1] = dbd & 0x18;
|
| 2397 | cmd[2] = modepage;
|
| 2398 | cmd[3] = subpage;
|
| 2399 |
|
| 2400 | sshdr = exec_args.sshdr;
|
| 2401 |
|
| 2402 | retry:
|
| 2403 | use_10_for_ms = sdev->use_10_for_ms || len > 255;
|
| 2404 |
|
| 2405 | if (use_10_for_ms) {
|
| 2406 | if (len < 8 || len > 65535)
|
| 2407 | return -EINVAL;
|
| 2408 |
|
| 2409 | cmd[0] = MODE_SENSE_10;
|
| 2410 | put_unaligned_be16(len, &cmd[7]);
|
| 2411 | header_length = 8;
|
| 2412 | } else {
|
| 2413 | if (len < 4)
|
| 2414 | return -EINVAL;
|
| 2415 |
|
| 2416 | cmd[0] = MODE_SENSE;
|
| 2417 | cmd[4] = len;
|
| 2418 | header_length = 4;
|
| 2419 | }
|
| 2420 |
|
| 2421 | memset(buffer, 0, len);
|
| 2422 |
|
| 2423 | result = scsi_execute_cmd(sdev, cmd, REQ_OP_DRV_IN, buffer, len,
|
| 2424 | timeout, retries, &exec_args);
|
| 2425 | if (result < 0)
|
| 2426 | return result;
|
| 2427 |
|
| 2428 | |
| 2429 | * ILLEGAL REQUEST sense return identifies the actual command
|
| 2430 | * byte as the problem. MODE_SENSE commands can return
|
| 2431 | * ILLEGAL REQUEST if the code page isn't supported
|
| 2432 |
|
| 2433 | if (!scsi_status_is_good(result)) {
|
| 2434 | if (scsi_sense_valid(sshdr)) {
|
| 2435 | if ((sshdr->sense_key == ILLEGAL_REQUEST) &&
|
| 2436 | (sshdr->asc == 0x20) && (sshdr->ascq == 0)) {
|
| 2437 | |
| 2438 | * Invalid command operation code: retry using
|
| 2439 | * MODE SENSE(6) if this was a MODE SENSE(10)
|
| 2440 | * request, except if the request mode page is
|
| 2441 | * too large for MODE SENSE single byte
|
| 2442 | * allocation length field.
|
| 2443 |
|
| 2444 | if (use_10_for_ms) {
|
| 2445 | if (len > 255)
|
| 2446 | return -EIO;
|
| 2447 | sdev->use_10_for_ms = 0;
|
| 2448 | goto retry;
|
| 2449 | }
|
| 2450 | }
|
| 2451 | }
|
| 2452 | return -EIO;
|
| 2453 | }
|
| 2454 | if (unlikely(buffer[0] == 0x86 && buffer[1] == 0x0b &&
|
| 2455 | (modepage == 6 || modepage == 8))) {
|
| 2456 |
|
| 2457 | header_length = 0;
|
| 2458 | data->length = 13;
|
| 2459 | data->medium_type = 0;
|
| 2460 | data->device_specific = 0;
|
| 2461 | data->longlba = 0;
|
| 2462 | data->block_descriptor_length = 0;
|
| 2463 | } else if (use_10_for_ms) {
|
| 2464 | data->length = get_unaligned_be16(&buffer[0]) + 2;
|
| 2465 | data->medium_type = buffer[2];
|
| 2466 | data->device_specific = buffer[3];
|
| 2467 | data->longlba = buffer[4] & 0x01;
|
| 2468 | data->block_descriptor_length = get_unaligned_be16(&buffer[6]);
|
| 2469 | } else {
|
| 2470 | data->length = buffer[0] + 1;
|
| 2471 | data->medium_type = buffer[1];
|
| 2472 | data->device_specific = buffer[2];
|
| 2473 | data->block_descriptor_length = buffer[3];
|
| 2474 | }
|
| 2475 | data->header_length = header_length;
|
| 2476 |
|
| 2477 | return 0;
|
| 2478 | }
|
| 2479 | EXPORT_SYMBOL(scsi_mode_sense);
|
| 2480 |
|
| 2481 | |
| 2482 | * scsi_test_unit_ready - test if unit is ready
|
| 2483 | * @sdev: scsi device to change the state of.
|
| 2484 | * @timeout: command timeout
|
| 2485 | * @retries: number of retries before failing
|
| 2486 | * @sshdr: outpout pointer for decoded sense information.
|
| 2487 | *
|
| 2488 | * Returns zero if successful or an error if TUR failed. For
|
| 2489 | * removable media, UNIT_ATTENTION sets ->changed flag.
|
| 2490 | *
|
| 2491 | int
|
| 2492 | scsi_test_unit_ready(struct scsi_device *sdev, int timeout, int retries,
|
| 2493 | struct scsi_sense_hdr *sshdr)
|
| 2494 | {
|
| 2495 | char cmd[] = {
|
| 2496 | TEST_UNIT_READY, 0, 0, 0, 0, 0,
|
| 2497 | };
|
| 2498 | const struct scsi_exec_args exec_args = {
|
| 2499 | .sshdr = sshdr,
|
| 2500 | };
|
| 2501 | int result;
|
| 2502 |
|
| 2503 |
|
| 2504 | do {
|
| 2505 | result = scsi_execute_cmd(sdev, cmd, REQ_OP_DRV_IN, NULL, 0,
|
| 2506 | timeout, 1, &exec_args);
|
| 2507 | if (sdev->removable && result > 0 && scsi_sense_valid(sshdr) &&
|
| 2508 | sshdr->sense_key == UNIT_ATTENTION)
|
| 2509 | sdev->changed = 1;
|
| 2510 | } while (result > 0 && scsi_sense_valid(sshdr) &&
|
| 2511 | sshdr->sense_key == UNIT_ATTENTION && --retries);
|
| 2512 |
|
| 2513 | return result;
|
| 2514 | }
|
| 2515 | EXPORT_SYMBOL(scsi_test_unit_ready);
|
| 2516 |
|
| 2517 | |
| 2518 | * scsi_device_set_state - Take the given device through the device state model.
|
| 2519 | * @sdev: scsi device to change the state of.
|
| 2520 | * @state: state to change to.
|
| 2521 | *
|
| 2522 | * Returns zero if successful or an error if the requested
|
| 2523 | * transition is illegal.
|
| 2524 |
|
| 2525 | int
|
| 2526 | scsi_device_set_state(struct scsi_device *sdev, enum scsi_device_state state)
|
| 2527 | {
|
| 2528 | enum scsi_device_state oldstate = sdev->sdev_state;
|
| 2529 |
|
| 2530 | if (state == oldstate)
|
| 2531 | return 0;
|
| 2532 |
|
| 2533 | switch (state) {
|
| 2534 | case SDEV_CREATED:
|
| 2535 | switch (oldstate) {
|
| 2536 | case SDEV_CREATED_BLOCK:
|
| 2537 | break;
|
| 2538 | default:
|
| 2539 | goto illegal;
|
| 2540 | }
|
| 2541 | break;
|
| 2542 |
|
| 2543 | case SDEV_RUNNING:
|
| 2544 | switch (oldstate) {
|
| 2545 | case SDEV_CREATED:
|
| 2546 | case SDEV_OFFLINE:
|
| 2547 | case SDEV_TRANSPORT_OFFLINE:
|
| 2548 | case SDEV_QUIESCE:
|
| 2549 | case SDEV_BLOCK:
|
| 2550 | break;
|
| 2551 | default:
|
| 2552 | goto illegal;
|
| 2553 | }
|
| 2554 | break;
|
| 2555 |
|
| 2556 | case SDEV_QUIESCE:
|
| 2557 | switch (oldstate) {
|
| 2558 | case SDEV_RUNNING:
|
| 2559 | case SDEV_OFFLINE:
|
| 2560 | case SDEV_TRANSPORT_OFFLINE:
|
| 2561 | break;
|
| 2562 | default:
|
| 2563 | goto illegal;
|
| 2564 | }
|
| 2565 | break;
|
| 2566 |
|
| 2567 | case SDEV_OFFLINE:
|
| 2568 | case SDEV_TRANSPORT_OFFLINE:
|
| 2569 | switch (oldstate) {
|
| 2570 | case SDEV_CREATED:
|
| 2571 | case SDEV_RUNNING:
|
| 2572 | case SDEV_QUIESCE:
|
| 2573 | case SDEV_BLOCK:
|
| 2574 | break;
|
| 2575 | default:
|
| 2576 | goto illegal;
|
| 2577 | }
|
| 2578 | break;
|
| 2579 |
|
| 2580 | case SDEV_BLOCK:
|
| 2581 | switch (oldstate) {
|
| 2582 | case SDEV_RUNNING:
|
| 2583 | case SDEV_CREATED_BLOCK:
|
| 2584 | case SDEV_QUIESCE:
|
| 2585 | case SDEV_OFFLINE:
|
| 2586 | break;
|
| 2587 | default:
|
| 2588 | goto illegal;
|
| 2589 | }
|
| 2590 | break;
|
| 2591 |
|
| 2592 | case SDEV_CREATED_BLOCK:
|
| 2593 | switch (oldstate) {
|
| 2594 | case SDEV_CREATED:
|
| 2595 | break;
|
| 2596 | default:
|
| 2597 | goto illegal;
|
| 2598 | }
|
| 2599 | break;
|
| 2600 |
|
| 2601 | case SDEV_CANCEL:
|
| 2602 | switch (oldstate) {
|
| 2603 | case SDEV_CREATED:
|
| 2604 | case SDEV_RUNNING:
|
| 2605 | case SDEV_QUIESCE:
|
| 2606 | case SDEV_OFFLINE:
|
| 2607 | case SDEV_TRANSPORT_OFFLINE:
|
| 2608 | break;
|
| 2609 | default:
|
| 2610 | goto illegal;
|
| 2611 | }
|
| 2612 | break;
|
| 2613 |
|
| 2614 | case SDEV_DEL:
|
| 2615 | switch (oldstate) {
|
| 2616 | case SDEV_CREATED:
|
| 2617 | case SDEV_RUNNING:
|
| 2618 | case SDEV_OFFLINE:
|
| 2619 | case SDEV_TRANSPORT_OFFLINE:
|
| 2620 | case SDEV_CANCEL:
|
| 2621 | case SDEV_BLOCK:
|
| 2622 | case SDEV_CREATED_BLOCK:
|
| 2623 | break;
|
| 2624 | default:
|
| 2625 | goto illegal;
|
| 2626 | }
|
| 2627 | break;
|
| 2628 |
|
| 2629 | }
|
| 2630 | sdev->offline_already = false;
|
| 2631 | sdev->sdev_state = state;
|
| 2632 | return 0;
|
| 2633 |
|
| 2634 | illegal:
|
| 2635 | SCSI_LOG_ERROR_RECOVERY(1,
|
| 2636 | sdev_printk(KERN_ERR, sdev,
|
| 2637 | "Illegal state transition %s->%s",
|
| 2638 | scsi_device_state_name(oldstate),
|
| 2639 | scsi_device_state_name(state))
|
| 2640 | );
|
| 2641 | return -EINVAL;
|
| 2642 | }
|
| 2643 | EXPORT_SYMBOL(scsi_device_set_state);
|
| 2644 |
|
| 2645 | |
| 2646 | * scsi_evt_emit - emit a single SCSI device uevent
|
| 2647 | * @sdev: associated SCSI device
|
| 2648 | * @evt: event to emit
|
| 2649 | *
|
| 2650 | * Send a single uevent (scsi_event) to the associated scsi_device.
|
| 2651 |
|
| 2652 | static void scsi_evt_emit(struct scsi_device *sdev, struct scsi_event *evt)
|
| 2653 | {
|
| 2654 | int idx = 0;
|
| 2655 | char *envp[3];
|
| 2656 |
|
| 2657 | switch (evt->evt_type) {
|
| 2658 | case SDEV_EVT_MEDIA_CHANGE:
|
| 2659 | envp[idx++] = "SDEV_MEDIA_CHANGE=1";
|
| 2660 | break;
|
| 2661 | case SDEV_EVT_INQUIRY_CHANGE_REPORTED:
|
| 2662 | scsi_rescan_device(sdev);
|
| 2663 | envp[idx++] = "SDEV_UA=INQUIRY_DATA_HAS_CHANGED";
|
| 2664 | break;
|
| 2665 | case SDEV_EVT_CAPACITY_CHANGE_REPORTED:
|
| 2666 | envp[idx++] = "SDEV_UA=CAPACITY_DATA_HAS_CHANGED";
|
| 2667 | break;
|
| 2668 | case SDEV_EVT_SOFT_THRESHOLD_REACHED_REPORTED:
|
| 2669 | envp[idx++] = "SDEV_UA=THIN_PROVISIONING_SOFT_THRESHOLD_REACHED";
|
| 2670 | break;
|
| 2671 | case SDEV_EVT_MODE_PARAMETER_CHANGE_REPORTED:
|
| 2672 | envp[idx++] = "SDEV_UA=MODE_PARAMETERS_CHANGED";
|
| 2673 | break;
|
| 2674 | case SDEV_EVT_LUN_CHANGE_REPORTED:
|
| 2675 | envp[idx++] = "SDEV_UA=REPORTED_LUNS_DATA_HAS_CHANGED";
|
| 2676 | break;
|
| 2677 | case SDEV_EVT_ALUA_STATE_CHANGE_REPORTED:
|
| 2678 | envp[idx++] = "SDEV_UA=ASYMMETRIC_ACCESS_STATE_CHANGED";
|
| 2679 | break;
|
| 2680 | case SDEV_EVT_POWER_ON_RESET_OCCURRED:
|
| 2681 | envp[idx++] = "SDEV_UA=POWER_ON_RESET_OCCURRED";
|
| 2682 | break;
|
| 2683 | default:
|
| 2684 |
|
| 2685 | break;
|
| 2686 | }
|
| 2687 |
|
| 2688 | envp[idx++] = NULL;
|
| 2689 |
|
| 2690 | kobject_uevent_env(&sdev->sdev_gendev.kobj, KOBJ_CHANGE, envp);
|
| 2691 | }
|
| 2692 |
|
| 2693 | |
| 2694 | * scsi_evt_thread - send a uevent for each scsi event
|
| 2695 | * @work: work struct for scsi_device
|
| 2696 | *
|
| 2697 | * Dispatch queued events to their associated scsi_device kobjects
|
| 2698 | * as uevents.
|
| 2699 |
|
| 2700 | void scsi_evt_thread(struct work_struct *work)
|
| 2701 | {
|
| 2702 | struct scsi_device *sdev;
|
| 2703 | enum scsi_device_event evt_type;
|
| 2704 | LIST_HEAD(event_list);
|
| 2705 |
|
| 2706 | sdev = container_of(work, struct scsi_device, event_work);
|
| 2707 |
|
| 2708 | for (evt_type = SDEV_EVT_FIRST; evt_type <= SDEV_EVT_LAST; evt_type++)
|
| 2709 | if (test_and_clear_bit(evt_type, sdev->pending_events))
|
| 2710 | sdev_evt_send_simple(sdev, evt_type, GFP_KERNEL);
|
| 2711 |
|
| 2712 | while (1) {
|
| 2713 | struct scsi_event *evt;
|
| 2714 | struct list_head *this, *tmp;
|
| 2715 | unsigned long flags;
|
| 2716 |
|
| 2717 | spin_lock_irqsave(&sdev->list_lock, flags);
|
| 2718 | list_splice_init(&sdev->event_list, &event_list);
|
| 2719 | spin_unlock_irqrestore(&sdev->list_lock, flags);
|
| 2720 |
|
| 2721 | if (list_empty(&event_list))
|
| 2722 | break;
|
| 2723 |
|
| 2724 | list_for_each_safe(this, tmp, &event_list) {
|
| 2725 | evt = list_entry(this, struct scsi_event, node);
|
| 2726 | list_del(&evt->node);
|
| 2727 | scsi_evt_emit(sdev, evt);
|
| 2728 | kfree(evt);
|
| 2729 | }
|
| 2730 | }
|
| 2731 | }
|
| 2732 |
|
| 2733 | |
| 2734 | * sdev_evt_send - send asserted event to uevent thread
|
| 2735 | * @sdev: scsi_device event occurred on
|
| 2736 | * @evt: event to send
|
| 2737 | *
|
| 2738 | * Assert scsi device event asynchronously.
|
| 2739 |
|
| 2740 | void sdev_evt_send(struct scsi_device *sdev, struct scsi_event *evt)
|
| 2741 | {
|
| 2742 | unsigned long flags;
|
| 2743 |
|
| 2744 | #if 0 |
| 2745 | /* FIXME: currently this check eliminates all media change events
|
| 2746 | * for polled devices. Need to update to discriminate between AN
|
| 2747 | * and polled events */
|
| 2748 | if (!test_bit(evt->evt_type, sdev->supported_events)) {
|
| 2749 | kfree(evt);
|
| 2750 | return;
|
| 2751 | }
|
| 2752 | #endif
|
| 2753 |
|
| 2754 | spin_lock_irqsave(&sdev->list_lock, flags);
|
| 2755 | list_add_tail(&evt->node, &sdev->event_list);
|
| 2756 | schedule_work(&sdev->event_work);
|
| 2757 | spin_unlock_irqrestore(&sdev->list_lock, flags);
|
| 2758 | }
|
| 2759 | EXPORT_SYMBOL_GPL(sdev_evt_send);
|
| 2760 |
|
| 2761 | |
| 2762 | * sdev_evt_alloc - allocate a new scsi event
|
| 2763 | * @evt_type: type of event to allocate
|
| 2764 | * @gfpflags: GFP flags for allocation
|
| 2765 | *
|
| 2766 | * Allocates and returns a new scsi_event.
|
| 2767 |
|
| 2768 | struct scsi_event *sdev_evt_alloc(enum scsi_device_event evt_type,
|
| 2769 | gfp_t gfpflags)
|
| 2770 | {
|
| 2771 | struct scsi_event *evt = kzalloc_obj(struct scsi_event, gfpflags);
|
| 2772 | if (!evt)
|
| 2773 | return NULL;
|
| 2774 |
|
| 2775 | evt->evt_type = evt_type;
|
| 2776 | INIT_LIST_HEAD(&evt->node);
|
| 2777 |
|
| 2778 |
|
| 2779 | switch (evt_type) {
|
| 2780 | case SDEV_EVT_MEDIA_CHANGE:
|
| 2781 | case SDEV_EVT_INQUIRY_CHANGE_REPORTED:
|
| 2782 | case SDEV_EVT_CAPACITY_CHANGE_REPORTED:
|
| 2783 | case SDEV_EVT_SOFT_THRESHOLD_REACHED_REPORTED:
|
| 2784 | case SDEV_EVT_MODE_PARAMETER_CHANGE_REPORTED:
|
| 2785 | case SDEV_EVT_LUN_CHANGE_REPORTED:
|
| 2786 | case SDEV_EVT_ALUA_STATE_CHANGE_REPORTED:
|
| 2787 | case SDEV_EVT_POWER_ON_RESET_OCCURRED:
|
| 2788 | default:
|
| 2789 |
|
| 2790 | break;
|
| 2791 | }
|
| 2792 |
|
| 2793 | return evt;
|
| 2794 | }
|
| 2795 | EXPORT_SYMBOL_GPL(sdev_evt_alloc);
|
| 2796 |
|
| 2797 | |
| 2798 | * sdev_evt_send_simple - send asserted event to uevent thread
|
| 2799 | * @sdev: scsi_device event occurred on
|
| 2800 | * @evt_type: type of event to send
|
| 2801 | * @gfpflags: GFP flags for allocation
|
| 2802 | *
|
| 2803 | * Assert scsi device event asynchronously, given an event type.
|
| 2804 |
|
| 2805 | void sdev_evt_send_simple(struct scsi_device *sdev,
|
| 2806 | enum scsi_device_event evt_type, gfp_t gfpflags)
|
| 2807 | {
|
| 2808 | struct scsi_event *evt = sdev_evt_alloc(evt_type, gfpflags);
|
| 2809 | if (!evt) {
|
| 2810 | sdev_printk(KERN_ERR, sdev, "event %d eaten due to OOM\n",
|
| 2811 | evt_type);
|
| 2812 | return;
|
| 2813 | }
|
| 2814 |
|
| 2815 | sdev_evt_send(sdev, evt);
|
| 2816 | }
|
| 2817 | EXPORT_SYMBOL_GPL(sdev_evt_send_simple);
|
| 2818 |
|
| 2819 | |
| 2820 | * scsi_device_quiesce - Block all commands except power management.
|
| 2821 | * @sdev: scsi device to quiesce.
|
| 2822 | *
|
| 2823 | * This works by trying to transition to the SDEV_QUIESCE state
|
| 2824 | * (which must be a legal transition). When the device is in this
|
| 2825 | * state, only power management requests will be accepted, all others will
|
| 2826 | * be deferred.
|
| 2827 | *
|
| 2828 | * Must be called with user context, may sleep.
|
| 2829 | *
|
| 2830 | * Returns zero if successful or an error if not.
|
| 2831 |
|
| 2832 | int
|
| 2833 | scsi_device_quiesce(struct scsi_device *sdev)
|
| 2834 | {
|
| 2835 | struct request_queue *q = sdev->request_queue;
|
| 2836 | unsigned int memflags;
|
| 2837 | int err;
|
| 2838 |
|
| 2839 | |
| 2840 | * It is allowed to call scsi_device_quiesce() multiple times from
|
| 2841 | * the same context but concurrent scsi_device_quiesce() calls are
|
| 2842 | * not allowed.
|
| 2843 |
|
| 2844 | WARN_ON_ONCE(sdev->quiesced_by && sdev->quiesced_by != current);
|
| 2845 |
|
| 2846 | if (sdev->quiesced_by == current)
|
| 2847 | return 0;
|
| 2848 |
|
| 2849 | blk_set_pm_only(q);
|
| 2850 |
|
| 2851 | memflags = blk_mq_freeze_queue(q);
|
| 2852 | |
| 2853 | * Ensure that the effect of blk_set_pm_only() will be visible
|
| 2854 | * for percpu_ref_tryget() callers that occur after the queue
|
| 2855 | * unfreeze even if the queue was already frozen before this function
|
| 2856 | * was called. See also https://lwn.net/Articles/573497/.
|
| 2857 |
|
| 2858 | synchronize_rcu();
|
| 2859 | blk_mq_unfreeze_queue(q, memflags);
|
| 2860 |
|
| 2861 | mutex_lock(&sdev->state_mutex);
|
| 2862 | err = scsi_device_set_state(sdev, SDEV_QUIESCE);
|
| 2863 | if (err == 0)
|
| 2864 | sdev->quiesced_by = current;
|
| 2865 | else
|
| 2866 | blk_clear_pm_only(q);
|
| 2867 | mutex_unlock(&sdev->state_mutex);
|
| 2868 |
|
| 2869 | return err;
|
| 2870 | }
|
| 2871 | EXPORT_SYMBOL(scsi_device_quiesce);
|
| 2872 |
|
| 2873 | |
| 2874 | * scsi_device_resume - Restart user issued commands to a quiesced device.
|
| 2875 | * @sdev: scsi device to resume.
|
| 2876 | *
|
| 2877 | * Moves the device from quiesced back to running and restarts the
|
| 2878 | * queues.
|
| 2879 | *
|
| 2880 | * Must be called with user context, may sleep.
|
| 2881 |
|
| 2882 | void scsi_device_resume(struct scsi_device *sdev)
|
| 2883 | {
|
| 2884 | |
| 2885 | * so assume the state is being managed elsewhere (for example
|
| 2886 | * device deleted during suspend)
|
| 2887 |
|
| 2888 | mutex_lock(&sdev->state_mutex);
|
| 2889 | if (sdev->sdev_state == SDEV_QUIESCE)
|
| 2890 | scsi_device_set_state(sdev, SDEV_RUNNING);
|
| 2891 | if (sdev->quiesced_by) {
|
| 2892 | sdev->quiesced_by = NULL;
|
| 2893 | blk_clear_pm_only(sdev->request_queue);
|
| 2894 | }
|
| 2895 | mutex_unlock(&sdev->state_mutex);
|
| 2896 | }
|
| 2897 | EXPORT_SYMBOL(scsi_device_resume);
|
| 2898 |
|
| 2899 | static void
|
| 2900 | device_quiesce_fn(struct scsi_device *sdev, void *data)
|
| 2901 | {
|
| 2902 | scsi_device_quiesce(sdev);
|
| 2903 | }
|
| 2904 |
|
| 2905 | void
|
| 2906 | scsi_target_quiesce(struct scsi_target *starget)
|
| 2907 | {
|
| 2908 | starget_for_each_device(starget, NULL, device_quiesce_fn);
|
| 2909 | }
|
| 2910 | EXPORT_SYMBOL(scsi_target_quiesce);
|
| 2911 |
|
| 2912 | static void
|
| 2913 | device_resume_fn(struct scsi_device *sdev, void *data)
|
| 2914 | {
|
| 2915 | scsi_device_resume(sdev);
|
| 2916 | }
|
| 2917 |
|
| 2918 | void
|
| 2919 | scsi_target_resume(struct scsi_target *starget)
|
| 2920 | {
|
| 2921 | starget_for_each_device(starget, NULL, device_resume_fn);
|
| 2922 | }
|
| 2923 | EXPORT_SYMBOL(scsi_target_resume);
|
| 2924 |
|
| 2925 | static int __scsi_internal_device_block_nowait(struct scsi_device *sdev)
|
| 2926 | {
|
| 2927 | if (scsi_device_set_state(sdev, SDEV_BLOCK))
|
| 2928 | return scsi_device_set_state(sdev, SDEV_CREATED_BLOCK);
|
| 2929 |
|
| 2930 | return 0;
|
| 2931 | }
|
| 2932 |
|
| 2933 | void scsi_start_queue(struct scsi_device *sdev)
|
| 2934 | {
|
| 2935 | if (cmpxchg(&sdev->queue_stopped, 1, 0))
|
| 2936 | blk_mq_unquiesce_queue(sdev->request_queue);
|
| 2937 | }
|
| 2938 |
|
| 2939 | static void scsi_stop_queue(struct scsi_device *sdev)
|
| 2940 | {
|
| 2941 | |
| 2942 | * The atomic variable of ->queue_stopped covers that
|
| 2943 | * blk_mq_quiesce_queue* is balanced with blk_mq_unquiesce_queue.
|
| 2944 | *
|
| 2945 | * The caller needs to wait until quiesce is done.
|
| 2946 |
|
| 2947 | if (!cmpxchg(&sdev->queue_stopped, 0, 1))
|
| 2948 | blk_mq_quiesce_queue_nowait(sdev->request_queue);
|
| 2949 | }
|
| 2950 |
|
| 2951 | |
| 2952 | * scsi_internal_device_block_nowait - try to transition to the SDEV_BLOCK state
|
| 2953 | * @sdev: device to block
|
| 2954 | *
|
| 2955 | * Pause SCSI command processing on the specified device. Does not sleep.
|
| 2956 | *
|
| 2957 | * Returns zero if successful or a negative error code upon failure.
|
| 2958 | *
|
| 2959 | * Notes:
|
| 2960 | * This routine transitions the device to the SDEV_BLOCK state (which must be
|
| 2961 | * a legal transition). When the device is in this state, command processing
|
| 2962 | * is paused until the device leaves the SDEV_BLOCK state. See also
|
| 2963 | * scsi_internal_device_unblock_nowait().
|
| 2964 |
|
| 2965 | int scsi_internal_device_block_nowait(struct scsi_device *sdev)
|
| 2966 | {
|
| 2967 | int ret = __scsi_internal_device_block_nowait(sdev);
|
| 2968 |
|
| 2969 | |
| 2970 | * The device has transitioned to SDEV_BLOCK. Stop the
|
| 2971 | * block layer from calling the midlayer with this device's
|
| 2972 | * request queue.
|
| 2973 |
|
| 2974 | if (!ret)
|
| 2975 | scsi_stop_queue(sdev);
|
| 2976 | return ret;
|
| 2977 | }
|
| 2978 | EXPORT_SYMBOL_GPL(scsi_internal_device_block_nowait);
|
| 2979 |
|
| 2980 | |
| 2981 | * scsi_device_block - try to transition to the SDEV_BLOCK state
|
| 2982 | * @sdev: device to block
|
| 2983 | * @data: dummy argument, ignored
|
| 2984 | *
|
| 2985 | * Pause SCSI command processing on the specified device. Callers must wait
|
| 2986 | * until all ongoing scsi_queue_rq() calls have finished after this function
|
| 2987 | * returns.
|
| 2988 | *
|
| 2989 | * Note:
|
| 2990 | * This routine transitions the device to the SDEV_BLOCK state (which must be
|
| 2991 | * a legal transition). When the device is in this state, command processing
|
| 2992 | * is paused until the device leaves the SDEV_BLOCK state. See also
|
| 2993 | * scsi_internal_device_unblock().
|
| 2994 |
|
| 2995 | static void scsi_device_block(struct scsi_device *sdev, void *data)
|
| 2996 | {
|
| 2997 | int err;
|
| 2998 | enum scsi_device_state state;
|
| 2999 |
|
| 3000 | mutex_lock(&sdev->state_mutex);
|
| 3001 | err = __scsi_internal_device_block_nowait(sdev);
|
| 3002 | state = sdev->sdev_state;
|
| 3003 | if (err == 0)
|
| 3004 | |
| 3005 | * scsi_stop_queue() must be called with the state_mutex
|
| 3006 | * held. Otherwise a simultaneous scsi_start_queue() call
|
| 3007 | * might unquiesce the queue before we quiesce it.
|
| 3008 |
|
| 3009 | scsi_stop_queue(sdev);
|
| 3010 |
|
| 3011 | mutex_unlock(&sdev->state_mutex);
|
| 3012 |
|
| 3013 | WARN_ONCE(err, "%s: failed to block %s in state %d\n",
|
| 3014 | __func__, dev_name(&sdev->sdev_gendev), state);
|
| 3015 | }
|
| 3016 |
|
| 3017 | |
| 3018 | * scsi_internal_device_unblock_nowait - resume a device after a block request
|
| 3019 | * @sdev: device to resume
|
| 3020 | * @new_state: state to set the device to after unblocking
|
| 3021 | *
|
| 3022 | * Restart the device queue for a previously suspended SCSI device. Does not
|
| 3023 | * sleep.
|
| 3024 | *
|
| 3025 | * Returns zero if successful or a negative error code upon failure.
|
| 3026 | *
|
| 3027 | * Notes:
|
| 3028 | * This routine transitions the device to the SDEV_RUNNING state or to one of
|
| 3029 | * the offline states (which must be a legal transition) allowing the midlayer
|
| 3030 | * to goose the queue for this device.
|
| 3031 |
|
| 3032 | int scsi_internal_device_unblock_nowait(struct scsi_device *sdev,
|
| 3033 | enum scsi_device_state new_state)
|
| 3034 | {
|
| 3035 | switch (new_state) {
|
| 3036 | case SDEV_RUNNING:
|
| 3037 | case SDEV_TRANSPORT_OFFLINE:
|
| 3038 | break;
|
| 3039 | default:
|
| 3040 | return -EINVAL;
|
| 3041 | }
|
| 3042 |
|
| 3043 | |
| 3044 | * Try to transition the scsi device to SDEV_RUNNING or one of the
|
| 3045 | * offlined states and goose the device queue if successful.
|
| 3046 |
|
| 3047 | switch (sdev->sdev_state) {
|
| 3048 | case SDEV_BLOCK:
|
| 3049 | case SDEV_TRANSPORT_OFFLINE:
|
| 3050 | sdev->sdev_state = new_state;
|
| 3051 | break;
|
| 3052 | case SDEV_CREATED_BLOCK:
|
| 3053 | if (new_state == SDEV_TRANSPORT_OFFLINE ||
|
| 3054 | new_state == SDEV_OFFLINE)
|
| 3055 | sdev->sdev_state = new_state;
|
| 3056 | else
|
| 3057 | sdev->sdev_state = SDEV_CREATED;
|
| 3058 | break;
|
| 3059 | case SDEV_CANCEL:
|
| 3060 | case SDEV_OFFLINE:
|
| 3061 | break;
|
| 3062 | default:
|
| 3063 | return -EINVAL;
|
| 3064 | }
|
| 3065 | scsi_start_queue(sdev);
|
| 3066 |
|
| 3067 | return 0;
|
| 3068 | }
|
| 3069 | EXPORT_SYMBOL_GPL(scsi_internal_device_unblock_nowait);
|
| 3070 |
|
| 3071 | |
| 3072 | * scsi_internal_device_unblock - resume a device after a block request
|
| 3073 | * @sdev: device to resume
|
| 3074 | * @new_state: state to set the device to after unblocking
|
| 3075 | *
|
| 3076 | * Restart the device queue for a previously suspended SCSI device. May sleep.
|
| 3077 | *
|
| 3078 | * Returns zero if successful or a negative error code upon failure.
|
| 3079 | *
|
| 3080 | * Notes:
|
| 3081 | * This routine transitions the device to the SDEV_RUNNING state or to one of
|
| 3082 | * the offline states (which must be a legal transition) allowing the midlayer
|
| 3083 | * to goose the queue for this device.
|
| 3084 |
|
| 3085 | static int scsi_internal_device_unblock(struct scsi_device *sdev,
|
| 3086 | enum scsi_device_state new_state)
|
| 3087 | {
|
| 3088 | int ret;
|
| 3089 |
|
| 3090 | mutex_lock(&sdev->state_mutex);
|
| 3091 | ret = scsi_internal_device_unblock_nowait(sdev, new_state);
|
| 3092 | mutex_unlock(&sdev->state_mutex);
|
| 3093 |
|
| 3094 | return ret;
|
| 3095 | }
|
| 3096 |
|
| 3097 | static int
|
| 3098 | target_block(struct device *dev, void *data)
|
| 3099 | {
|
| 3100 | if (scsi_is_target_device(dev))
|
| 3101 | starget_for_each_device(to_scsi_target(dev), NULL,
|
| 3102 | scsi_device_block);
|
| 3103 | return 0;
|
| 3104 | }
|
| 3105 |
|
| 3106 | |
| 3107 | * scsi_block_targets - transition all SCSI child devices to SDEV_BLOCK state
|
| 3108 | * @dev: a parent device of one or more scsi_target devices
|
| 3109 | * @shost: the Scsi_Host to which this device belongs
|
| 3110 | *
|
| 3111 | * Iterate over all children of @dev, which should be scsi_target devices,
|
| 3112 | * and switch all subordinate scsi devices to SDEV_BLOCK state. Wait for
|
| 3113 | * ongoing scsi_queue_rq() calls to finish. May sleep.
|
| 3114 | *
|
| 3115 | * Note:
|
| 3116 | * @dev must not itself be a scsi_target device.
|
| 3117 |
|
| 3118 | void
|
| 3119 | scsi_block_targets(struct Scsi_Host *shost, struct device *dev)
|
| 3120 | {
|
| 3121 | WARN_ON_ONCE(scsi_is_target_device(dev));
|
| 3122 | device_for_each_child(dev, NULL, target_block);
|
| 3123 | blk_mq_wait_quiesce_done(&shost->tag_set);
|
| 3124 | }
|
| 3125 | EXPORT_SYMBOL_GPL(scsi_block_targets);
|
| 3126 |
|
| 3127 | static void
|
| 3128 | device_unblock(struct scsi_device *sdev, void *data)
|
| 3129 | {
|
| 3130 | scsi_internal_device_unblock(sdev, *(enum scsi_device_state *)data);
|
| 3131 | }
|
| 3132 |
|
| 3133 | static int
|
| 3134 | target_unblock(struct device *dev, void *data)
|
| 3135 | {
|
| 3136 | if (scsi_is_target_device(dev))
|
| 3137 | starget_for_each_device(to_scsi_target(dev), data,
|
| 3138 | device_unblock);
|
| 3139 | return 0;
|
| 3140 | }
|
| 3141 |
|
| 3142 | void
|
| 3143 | scsi_target_unblock(struct device *dev, enum scsi_device_state new_state)
|
| 3144 | {
|
| 3145 | if (scsi_is_target_device(dev))
|
| 3146 | starget_for_each_device(to_scsi_target(dev), &new_state,
|
| 3147 | device_unblock);
|
| 3148 | else
|
| 3149 | device_for_each_child(dev, &new_state, target_unblock);
|
| 3150 | }
|
| 3151 | EXPORT_SYMBOL_GPL(scsi_target_unblock);
|
| 3152 |
|
| 3153 | |
| 3154 | * scsi_host_block - Try to transition all logical units to the SDEV_BLOCK state
|
| 3155 | * @shost: device to block
|
| 3156 | *
|
| 3157 | * Pause SCSI command processing for all logical units associated with the SCSI
|
| 3158 | * host and wait until pending scsi_queue_rq() calls have finished.
|
| 3159 | *
|
| 3160 | * Returns zero if successful or a negative error code upon failure.
|
| 3161 |
|
| 3162 | int
|
| 3163 | scsi_host_block(struct Scsi_Host *shost)
|
| 3164 | {
|
| 3165 | struct scsi_device *sdev;
|
| 3166 | int ret;
|
| 3167 |
|
| 3168 | |
| 3169 | * Call scsi_internal_device_block_nowait so we can avoid
|
| 3170 | * calling synchronize_rcu() for each LUN.
|
| 3171 |
|
| 3172 | shost_for_each_device(sdev, shost) {
|
| 3173 | mutex_lock(&sdev->state_mutex);
|
| 3174 | ret = scsi_internal_device_block_nowait(sdev);
|
| 3175 | mutex_unlock(&sdev->state_mutex);
|
| 3176 | if (ret) {
|
| 3177 | scsi_device_put(sdev);
|
| 3178 | return ret;
|
| 3179 | }
|
| 3180 | }
|
| 3181 |
|
| 3182 |
|
| 3183 | blk_mq_wait_quiesce_done(&shost->tag_set);
|
| 3184 |
|
| 3185 | return 0;
|
| 3186 | }
|
| 3187 | EXPORT_SYMBOL_GPL(scsi_host_block);
|
| 3188 |
|
| 3189 | int
|
| 3190 | scsi_host_unblock(struct Scsi_Host *shost, int new_state)
|
| 3191 | {
|
| 3192 | struct scsi_device *sdev;
|
| 3193 | int ret = 0;
|
| 3194 |
|
| 3195 | shost_for_each_device(sdev, shost) {
|
| 3196 | ret = scsi_internal_device_unblock(sdev, new_state);
|
| 3197 | if (ret) {
|
| 3198 | scsi_device_put(sdev);
|
| 3199 | break;
|
| 3200 | }
|
| 3201 | }
|
| 3202 | return ret;
|
| 3203 | }
|
| 3204 | EXPORT_SYMBOL_GPL(scsi_host_unblock);
|
| 3205 |
|
| 3206 | |
| 3207 | * scsi_kmap_atomic_sg - find and atomically map an sg-elemnt
|
| 3208 | * @sgl: scatter-gather list
|
| 3209 | * @sg_count: number of segments in sg
|
| 3210 | * @offset: offset in bytes into sg, on return offset into the mapped area
|
| 3211 | * @len: bytes to map, on return number of bytes mapped
|
| 3212 | *
|
| 3213 | * Returns virtual address of the start of the mapped page
|
| 3214 |
|
| 3215 | void *scsi_kmap_atomic_sg(struct scatterlist *sgl, int sg_count,
|
| 3216 | size_t *offset, size_t *len)
|
| 3217 | {
|
| 3218 | int i;
|
| 3219 | size_t sg_len = 0, len_complete = 0;
|
| 3220 | struct scatterlist *sg;
|
| 3221 | struct page *page;
|
| 3222 |
|
| 3223 | WARN_ON(!irqs_disabled());
|
| 3224 |
|
| 3225 | for_each_sg(sgl, sg, sg_count, i) {
|
| 3226 | len_complete = sg_len;
|
| 3227 | sg_len += sg->length;
|
| 3228 | if (sg_len > *offset)
|
| 3229 | break;
|
| 3230 | }
|
| 3231 |
|
| 3232 | if (unlikely(i == sg_count)) {
|
| 3233 | printk(KERN_ERR "%s: Bytes in sg: %zu, requested offset %zu, "
|
| 3234 | "elements %d\n",
|
| 3235 | __func__, sg_len, *offset, sg_count);
|
| 3236 | WARN_ON(1);
|
| 3237 | return NULL;
|
| 3238 | }
|
| 3239 |
|
| 3240 |
|
| 3241 | *offset = *offset - len_complete + sg->offset;
|
| 3242 |
|
| 3243 | page = sg_page(sg) + (*offset >> PAGE_SHIFT);
|
| 3244 | *offset &= ~PAGE_MASK;
|
| 3245 |
|
| 3246 |
|
| 3247 | sg_len = PAGE_SIZE - *offset;
|
| 3248 | if (*len > sg_len)
|
| 3249 | *len = sg_len;
|
| 3250 |
|
| 3251 | return kmap_atomic(page);
|
| 3252 | }
|
| 3253 | EXPORT_SYMBOL(scsi_kmap_atomic_sg);
|
| 3254 |
|
| 3255 | |
| 3256 | * scsi_kunmap_atomic_sg - atomically unmap a virtual address, previously mapped with scsi_kmap_atomic_sg
|
| 3257 | * @virt: virtual address to be unmapped
|
| 3258 |
|
| 3259 | void scsi_kunmap_atomic_sg(void *virt)
|
| 3260 | {
|
| 3261 | kunmap_atomic(virt);
|
| 3262 | }
|
| 3263 | EXPORT_SYMBOL(scsi_kunmap_atomic_sg);
|
| 3264 |
|
| 3265 | void sdev_disable_disk_events(struct scsi_device *sdev)
|
| 3266 | {
|
| 3267 | atomic_inc(&sdev->disk_events_disable_depth);
|
| 3268 | }
|
| 3269 | EXPORT_SYMBOL(sdev_disable_disk_events);
|
| 3270 |
|
| 3271 | void sdev_enable_disk_events(struct scsi_device *sdev)
|
| 3272 | {
|
| 3273 | if (WARN_ON_ONCE(atomic_read(&sdev->disk_events_disable_depth) <= 0))
|
| 3274 | return;
|
| 3275 | atomic_dec(&sdev->disk_events_disable_depth);
|
| 3276 | }
|
| 3277 | EXPORT_SYMBOL(sdev_enable_disk_events);
|
| 3278 |
|
| 3279 | static unsigned char designator_prio(const unsigned char *d)
|
| 3280 | {
|
| 3281 | if (d[1] & 0x30)
|
| 3282 |
|
| 3283 | return 0;
|
| 3284 |
|
| 3285 | if (d[3] == 0)
|
| 3286 |
|
| 3287 | return 0;
|
| 3288 |
|
| 3289 | |
| 3290 | * Order of preference for lun descriptor:
|
| 3291 | * - SCSI name string
|
| 3292 | * - NAA IEEE Registered Extended
|
| 3293 | * - EUI-64 based 16-byte
|
| 3294 | * - EUI-64 based 12-byte
|
| 3295 | * - NAA IEEE Registered
|
| 3296 | * - NAA IEEE Extended
|
| 3297 | * - EUI-64 based 8-byte
|
| 3298 | * - SCSI name string (truncated)
|
| 3299 | * - T10 Vendor ID
|
| 3300 | * as longer descriptors reduce the likelyhood
|
| 3301 | * of identification clashes.
|
| 3302 |
|
| 3303 |
|
| 3304 | switch (d[1] & 0xf) {
|
| 3305 | case 8:
|
| 3306 |
|
| 3307 | return 9;
|
| 3308 | case 3:
|
| 3309 | switch (d[4] >> 4) {
|
| 3310 | case 6:
|
| 3311 |
|
| 3312 | return 8;
|
| 3313 | case 5:
|
| 3314 |
|
| 3315 | return 5;
|
| 3316 | case 4:
|
| 3317 |
|
| 3318 | return 4;
|
| 3319 | case 3:
|
| 3320 |
|
| 3321 | return 1;
|
| 3322 | default:
|
| 3323 | break;
|
| 3324 | }
|
| 3325 | break;
|
| 3326 | case 2:
|
| 3327 | switch (d[3]) {
|
| 3328 | case 16:
|
| 3329 |
|
| 3330 | return 7;
|
| 3331 | case 12:
|
| 3332 |
|
| 3333 | return 6;
|
| 3334 | case 8:
|
| 3335 |
|
| 3336 | return 3;
|
| 3337 | default:
|
| 3338 | break;
|
| 3339 | }
|
| 3340 | break;
|
| 3341 | case 1:
|
| 3342 |
|
| 3343 | return 1;
|
| 3344 | default:
|
| 3345 | break;
|
| 3346 | }
|
| 3347 |
|
| 3348 | return 0;
|
| 3349 | }
|
| 3350 |
|
| 3351 | |
| 3352 | * scsi_vpd_lun_id - return a unique device identification
|
| 3353 | * @sdev: SCSI device
|
| 3354 | * @id: buffer for the identification
|
| 3355 | * @id_len: length of the buffer
|
| 3356 | *
|
| 3357 | * Copies a unique device identification into @id based
|
| 3358 | * on the information in the VPD page 0x83 of the device.
|
| 3359 | * The string will be formatted as a SCSI name string.
|
| 3360 | *
|
| 3361 | * Returns the length of the identification or error on failure.
|
| 3362 | * If the identifier is longer than the supplied buffer the actual
|
| 3363 | * identifier length is returned and the buffer is not zero-padded.
|
| 3364 |
|
| 3365 | int scsi_vpd_lun_id(struct scsi_device *sdev, char *id, size_t id_len)
|
| 3366 | {
|
| 3367 | u8 cur_id_prio = 0;
|
| 3368 | u8 cur_id_size = 0;
|
| 3369 | const unsigned char *d, *cur_id_str;
|
| 3370 | const struct scsi_vpd *vpd_pg83;
|
| 3371 | int id_size = -EINVAL;
|
| 3372 |
|
| 3373 | rcu_read_lock();
|
| 3374 | vpd_pg83 = rcu_dereference(sdev->vpd_pg83);
|
| 3375 | if (!vpd_pg83) {
|
| 3376 | rcu_read_unlock();
|
| 3377 | return -ENXIO;
|
| 3378 | }
|
| 3379 |
|
| 3380 |
|
| 3381 | if (id_len < 21) {
|
| 3382 | rcu_read_unlock();
|
| 3383 | return -EINVAL;
|
| 3384 | }
|
| 3385 |
|
| 3386 | memset(id, 0, id_len);
|
| 3387 | for (d = vpd_pg83->data + 4;
|
| 3388 | d < vpd_pg83->data + vpd_pg83->len;
|
| 3389 | d += d[3] + 4) {
|
| 3390 | u8 prio = designator_prio(d);
|
| 3391 |
|
| 3392 | if (prio == 0 || cur_id_prio > prio)
|
| 3393 | continue;
|
| 3394 |
|
| 3395 | switch (d[1] & 0xf) {
|
| 3396 | case 0x1:
|
| 3397 |
|
| 3398 | if (cur_id_size > d[3])
|
| 3399 | break;
|
| 3400 | cur_id_prio = prio;
|
| 3401 | cur_id_size = d[3];
|
| 3402 | if (cur_id_size + 4 > id_len)
|
| 3403 | cur_id_size = id_len - 4;
|
| 3404 | cur_id_str = d + 4;
|
| 3405 | id_size = snprintf(id, id_len, "t10.%*pE",
|
| 3406 | cur_id_size, cur_id_str);
|
| 3407 | break;
|
| 3408 | case 0x2:
|
| 3409 |
|
| 3410 | cur_id_prio = prio;
|
| 3411 | cur_id_size = d[3];
|
| 3412 | cur_id_str = d + 4;
|
| 3413 | switch (cur_id_size) {
|
| 3414 | case 8:
|
| 3415 | id_size = snprintf(id, id_len,
|
| 3416 | "eui.%8phN",
|
| 3417 | cur_id_str);
|
| 3418 | break;
|
| 3419 | case 12:
|
| 3420 | id_size = snprintf(id, id_len,
|
| 3421 | "eui.%12phN",
|
| 3422 | cur_id_str);
|
| 3423 | break;
|
| 3424 | case 16:
|
| 3425 | id_size = snprintf(id, id_len,
|
| 3426 | "eui.%16phN",
|
| 3427 | cur_id_str);
|
| 3428 | break;
|
| 3429 | default:
|
| 3430 | break;
|
| 3431 | }
|
| 3432 | break;
|
| 3433 | case 0x3:
|
| 3434 |
|
| 3435 | cur_id_prio = prio;
|
| 3436 | cur_id_size = d[3];
|
| 3437 | cur_id_str = d + 4;
|
| 3438 | switch (cur_id_size) {
|
| 3439 | case 8:
|
| 3440 | id_size = snprintf(id, id_len,
|
| 3441 | "naa.%8phN",
|
| 3442 | cur_id_str);
|
| 3443 | break;
|
| 3444 | case 16:
|
| 3445 | id_size = snprintf(id, id_len,
|
| 3446 | "naa.%16phN",
|
| 3447 | cur_id_str);
|
| 3448 | break;
|
| 3449 | default:
|
| 3450 | break;
|
| 3451 | }
|
| 3452 | break;
|
| 3453 | case 0x8:
|
| 3454 |
|
| 3455 | if (cur_id_size > d[3])
|
| 3456 | break;
|
| 3457 |
|
| 3458 | if (d[3] > id_len) {
|
| 3459 | prio = 2;
|
| 3460 | if (cur_id_prio > prio)
|
| 3461 | break;
|
| 3462 | }
|
| 3463 | cur_id_prio = prio;
|
| 3464 | cur_id_size = id_size = d[3];
|
| 3465 | cur_id_str = d + 4;
|
| 3466 | if (cur_id_size >= id_len)
|
| 3467 | cur_id_size = id_len - 1;
|
| 3468 | memcpy(id, cur_id_str, cur_id_size);
|
| 3469 | break;
|
| 3470 | default:
|
| 3471 | break;
|
| 3472 | }
|
| 3473 | }
|
| 3474 | rcu_read_unlock();
|
| 3475 |
|
| 3476 | return id_size;
|
| 3477 | }
|
| 3478 | EXPORT_SYMBOL(scsi_vpd_lun_id);
|
| 3479 |
|
| 3480 | |
| 3481 | * scsi_vpd_lun_serial - return a unique device serial number
|
| 3482 | * @sdev: SCSI device
|
| 3483 | * @sn: buffer for the serial number
|
| 3484 | * @sn_size: size of the buffer
|
| 3485 | *
|
| 3486 | * Copies the device serial number into @sn based on the information in
|
| 3487 | * the VPD page 0x80 of the device. The string will be null terminated
|
| 3488 | * and have leading and trailing whitespace stripped.
|
| 3489 | *
|
| 3490 | * Returns the length of the serial number or error on failure.
|
| 3491 |
|
| 3492 | int scsi_vpd_lun_serial(struct scsi_device *sdev, char *sn, size_t sn_size)
|
| 3493 | {
|
| 3494 | const struct scsi_vpd *vpd_pg80;
|
| 3495 | const unsigned char *d;
|
| 3496 | int len;
|
| 3497 |
|
| 3498 | guard(rcu)();
|
| 3499 | vpd_pg80 = rcu_dereference(sdev->vpd_pg80);
|
| 3500 | if (!vpd_pg80)
|
| 3501 | return -ENXIO;
|
| 3502 |
|
| 3503 | len = vpd_pg80->len - 4;
|
| 3504 | d = vpd_pg80->data + 4;
|
| 3505 |
|
| 3506 |
|
| 3507 | while (len > 0 && isspace(*d)) {
|
| 3508 | len--;
|
| 3509 | d++;
|
| 3510 | }
|
| 3511 |
|
| 3512 |
|
| 3513 | while (len > 0 && isspace(d[len - 1]))
|
| 3514 | len--;
|
| 3515 |
|
| 3516 | if (sn_size < len + 1)
|
| 3517 | return -EINVAL;
|
| 3518 |
|
| 3519 | memcpy(sn, d, len);
|
| 3520 | sn[len] = '\0';
|
| 3521 |
|
| 3522 | return len;
|
| 3523 | }
|
| 3524 | EXPORT_SYMBOL(scsi_vpd_lun_serial);
|
| 3525 |
|
| 3526 | |
| 3527 | * scsi_vpd_tpg_id - return a target port group identifier
|
| 3528 | * @sdev: SCSI device
|
| 3529 | * @rel_id: pointer to return relative target port in if not %NULL
|
| 3530 | *
|
| 3531 | * Returns the Target Port Group identifier from the information
|
| 3532 | * from VPD page 0x83 of the device.
|
| 3533 | * Optionally sets @rel_id to the relative target port on success.
|
| 3534 | *
|
| 3535 | * Return: the identifier or error on failure.
|
| 3536 |
|
| 3537 | int scsi_vpd_tpg_id(struct scsi_device *sdev, int *rel_id)
|
| 3538 | {
|
| 3539 | const unsigned char *d;
|
| 3540 | const struct scsi_vpd *vpd_pg83;
|
| 3541 | int group_id = -EAGAIN, rel_port = -1;
|
| 3542 |
|
| 3543 | rcu_read_lock();
|
| 3544 | vpd_pg83 = rcu_dereference(sdev->vpd_pg83);
|
| 3545 | if (!vpd_pg83) {
|
| 3546 | rcu_read_unlock();
|
| 3547 | return -ENXIO;
|
| 3548 | }
|
| 3549 |
|
| 3550 | d = vpd_pg83->data + 4;
|
| 3551 | while (d < vpd_pg83->data + vpd_pg83->len) {
|
| 3552 | switch (d[1] & 0xf) {
|
| 3553 | case 0x4:
|
| 3554 |
|
| 3555 | rel_port = get_unaligned_be16(&d[6]);
|
| 3556 | break;
|
| 3557 | case 0x5:
|
| 3558 |
|
| 3559 | group_id = get_unaligned_be16(&d[6]);
|
| 3560 | break;
|
| 3561 | default:
|
| 3562 | break;
|
| 3563 | }
|
| 3564 | d += d[3] + 4;
|
| 3565 | }
|
| 3566 | rcu_read_unlock();
|
| 3567 |
|
| 3568 | if (group_id >= 0 && rel_id && rel_port != -1)
|
| 3569 | *rel_id = rel_port;
|
| 3570 |
|
| 3571 | return group_id;
|
| 3572 | }
|
| 3573 | EXPORT_SYMBOL(scsi_vpd_tpg_id);
|
| 3574 |
|
| 3575 | |
| 3576 | * scsi_build_sense - build sense data for a command
|
| 3577 | * @scmd: scsi command for which the sense should be formatted
|
| 3578 | * @desc: Sense format (non-zero == descriptor format,
|
| 3579 | * 0 == fixed format)
|
| 3580 | * @key: Sense key
|
| 3581 | * @asc: Additional sense code
|
| 3582 | * @ascq: Additional sense code qualifier
|
| 3583 | *
|
| 3584 | *
|
| 3585 | void scsi_build_sense(struct scsi_cmnd *scmd, int desc, u8 key, u8 asc, u8 ascq)
|
| 3586 | {
|
| 3587 | scsi_build_sense_buffer(desc, scmd->sense_buffer, key, asc, ascq);
|
| 3588 | scmd->result = SAM_STAT_CHECK_CONDITION;
|
| 3589 | }
|
| 3590 | EXPORT_SYMBOL_GPL(scsi_build_sense);
|
| 3591 |
|
| 3592 | #ifdef CONFIG_SCSI_LIB_KUNIT_TEST
|
| 3593 | #include "scsi_lib_test.c"
|
| 3594 | #endif
|