};
#undef SP
-static struct kmem_cache *scsi_bidi_sdb_cache;
+struct kmem_cache *scsi_sdb_cache;
static void scsi_run_queue(struct request_queue *q);
{
struct Scsi_Host *host = cmd->device->host;
struct scsi_device *device = cmd->device;
+ struct scsi_target *starget = scsi_target(device);
struct request_queue *q = device->request_queue;
unsigned long flags;
* if a command is requeued with no other commands outstanding
* either for the device or for the host.
*/
- if (reason == SCSI_MLQUEUE_HOST_BUSY)
+ switch (reason) {
+ case SCSI_MLQUEUE_HOST_BUSY:
host->host_blocked = host->max_host_blocked;
- else if (reason == SCSI_MLQUEUE_DEVICE_BUSY)
+ break;
+ case SCSI_MLQUEUE_DEVICE_BUSY:
device->device_blocked = device->max_device_blocked;
+ break;
+ case SCSI_MLQUEUE_TARGET_BUSY:
+ starget->target_blocked = starget->max_target_blocked;
+ break;
+ }
/*
* Decrement the counters, since these commands are no longer
*/
blk_execute_rq(req->q, NULL, req, 1);
+ /*
+ * Some devices (USB mass-storage in particular) may transfer
+ * garbage data together with a residue indicating that the data
+ * is invalid. Prevent the garbage from being misinterpreted
+ * and prevent security leaks by zeroing out the excess data.
+ */
+ if (unlikely(req->data_len > 0 && req->data_len <= bufflen))
+ memset(buffer + (bufflen - req->data_len), 0, req->data_len);
+
ret = req->errors;
out:
blk_put_request(req);
scsi_set_resid(cmd, 0);
memset(cmd->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
if (cmd->cmd_len == 0)
- cmd->cmd_len = COMMAND_SIZE(cmd->cmnd[0]);
+ cmd->cmd_len = scsi_command_size(cmd->cmnd);
}
void scsi_device_unbusy(struct scsi_device *sdev)
{
struct Scsi_Host *shost = sdev->host;
+ struct scsi_target *starget = scsi_target(sdev);
unsigned long flags;
spin_lock_irqsave(shost->host_lock, flags);
shost->host_busy--;
+ starget->target_busy--;
if (unlikely(scsi_host_in_recovery(shost) &&
(shost->host_failed || shost->host_eh_scheduled)))
scsi_eh_wakeup(shost);
spin_unlock_irqrestore(shost->host_lock, flags);
}
+static inline int scsi_device_is_busy(struct scsi_device *sdev)
+{
+ if (sdev->device_busy >= sdev->queue_depth || sdev->device_blocked)
+ return 1;
+
+ return 0;
+}
+
+static inline int scsi_target_is_busy(struct scsi_target *starget)
+{
+ return ((starget->can_queue > 0 &&
+ starget->target_busy >= starget->can_queue) ||
+ starget->target_blocked);
+}
+
+static inline int scsi_host_is_busy(struct Scsi_Host *shost)
+{
+ if ((shost->can_queue > 0 && shost->host_busy >= shost->can_queue) ||
+ shost->host_blocked || shost->host_self_blocked)
+ return 1;
+
+ return 0;
+}
+
/*
* Function: scsi_run_queue()
*
*/
static void scsi_run_queue(struct request_queue *q)
{
- struct scsi_device *sdev = q->queuedata;
+ struct scsi_device *starved_head = NULL, *sdev = q->queuedata;
struct Scsi_Host *shost = sdev->host;
unsigned long flags;
scsi_single_lun_run(sdev);
spin_lock_irqsave(shost->host_lock, flags);
- while (!list_empty(&shost->starved_list) &&
- !shost->host_blocked && !shost->host_self_blocked &&
- !((shost->can_queue > 0) &&
- (shost->host_busy >= shost->can_queue))) {
+ while (!list_empty(&shost->starved_list) && !scsi_host_is_busy(shost)) {
+ int flagset;
+
/*
* As long as shost is accepting commands and we have
* starved queues, call blk_run_queue. scsi_request_fn
*/
sdev = list_entry(shost->starved_list.next,
struct scsi_device, starved_entry);
- list_del_init(&sdev->starved_entry);
- spin_unlock_irqrestore(shost->host_lock, flags);
+ /*
+ * The *queue_ready functions can add a device back onto the
+ * starved list's tail, so we must check for a infinite loop.
+ */
+ if (sdev == starved_head)
+ break;
+ if (!starved_head)
+ starved_head = sdev;
+ if (scsi_target_is_busy(scsi_target(sdev))) {
+ list_move_tail(&sdev->starved_entry,
+ &shost->starved_list);
+ continue;
+ }
- if (test_bit(QUEUE_FLAG_REENTER, &q->queue_flags) &&
- !test_and_set_bit(QUEUE_FLAG_REENTER,
- &sdev->request_queue->queue_flags)) {
- blk_run_queue(sdev->request_queue);
- clear_bit(QUEUE_FLAG_REENTER,
- &sdev->request_queue->queue_flags);
- } else
- blk_run_queue(sdev->request_queue);
+ list_del_init(&sdev->starved_entry);
+ spin_unlock(shost->host_lock);
+
+ spin_lock(sdev->request_queue->queue_lock);
+ flagset = test_bit(QUEUE_FLAG_REENTER, &q->queue_flags) &&
+ !test_bit(QUEUE_FLAG_REENTER,
+ &sdev->request_queue->queue_flags);
+ if (flagset)
+ queue_flag_set(QUEUE_FLAG_REENTER, sdev->request_queue);
+ __blk_run_queue(sdev->request_queue);
+ if (flagset)
+ queue_flag_clear(QUEUE_FLAG_REENTER, sdev->request_queue);
+ spin_unlock(sdev->request_queue->queue_lock);
- spin_lock_irqsave(shost->host_lock, flags);
- if (unlikely(!list_empty(&sdev->starved_entry)))
- /*
- * sdev lost a race, and was put back on the
- * starved list. This is unlikely but without this
- * in theory we could loop forever.
- */
- break;
+ spin_lock(shost->host_lock);
}
spin_unlock_irqrestore(shost->host_lock, flags);
leftover = req->data_len;
/* kill remainder if no retrys */
- if (error && blk_noretry_request(req))
+ if (error && scsi_noretry_cmd(cmd))
blk_end_request(req, error, leftover);
else {
if (requeue) {
struct scsi_data_buffer *bidi_sdb =
cmd->request->next_rq->special;
scsi_free_sgtable(bidi_sdb);
- kmem_cache_free(scsi_bidi_sdb_cache, bidi_sdb);
+ kmem_cache_free(scsi_sdb_cache, bidi_sdb);
cmd->request->next_rq->special = NULL;
}
+
+ if (scsi_prot_sg_count(cmd))
+ scsi_free_sgtable(cmd->prot_sdb);
}
EXPORT_SYMBOL(scsi_release_buffers);
* in req->data_len and req->next_rq->data_len. The upper-layer driver can
* decide what to do with this information.
*/
-void scsi_end_bidi_request(struct scsi_cmnd *cmd)
+static void scsi_end_bidi_request(struct scsi_cmnd *cmd)
{
struct request *req = cmd->request;
unsigned int dlen = req->data_len;
void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes)
{
int result = cmd->result;
- int this_count = scsi_bufflen(cmd);
+ int this_count;
struct request_queue *q = cmd->device->request_queue;
struct request *req = cmd->request;
- int clear_errors = 1;
+ int error = 0;
struct scsi_sense_hdr sshdr;
int sense_valid = 0;
int sense_deferred = 0;
if (blk_pc_request(req)) { /* SG_IO ioctl from block level */
req->errors = result;
if (result) {
- clear_errors = 0;
if (sense_valid && req->sense) {
/*
* SG_IO wants current and deferred errors
memcpy(req->sense, cmd->sense_buffer, len);
req->sense_len = len;
}
+ if (!sense_deferred)
+ error = -EIO;
}
if (scsi_bidi_cmnd(cmd)) {
/* will also release_buffers */
"%d bytes done.\n",
req->nr_sectors, good_bytes));
- if (clear_errors)
- req->errors = 0;
-
/* A number of bytes were successfully read. If there
* are leftovers and there is some kind of error
* (result != 0), retry the rest.
*/
- if (scsi_end_request(cmd, 0, good_bytes, result == 0) == NULL)
+ if (scsi_end_request(cmd, error, good_bytes, result == 0) == NULL)
return;
+ this_count = blk_rq_bytes(req);
/* good_bytes = 0, or (inclusive) there were leftovers and
* result = 0, so scsi_end_request couldn't retry.
* 6-byte command.
*/
scsi_requeue_command(q, cmd);
- return;
- } else {
+ } else if (sshdr.asc == 0x10) /* DIX */
+ scsi_end_request(cmd, -EIO, this_count, 0);
+ else
scsi_end_request(cmd, -EIO, this_count, 1);
+ return;
+ case ABORTED_COMMAND:
+ if (sshdr.asc == 0x10) { /* DIF */
+ scsi_end_request(cmd, -EIO, this_count, 0);
return;
}
break;
if (blk_bidi_rq(cmd->request)) {
struct scsi_data_buffer *bidi_sdb = kmem_cache_zalloc(
- scsi_bidi_sdb_cache, GFP_ATOMIC);
+ scsi_sdb_cache, GFP_ATOMIC);
if (!bidi_sdb) {
error = BLKPREP_DEFER;
goto err_exit;
goto err_exit;
}
+ if (blk_integrity_rq(cmd->request)) {
+ struct scsi_data_buffer *prot_sdb = cmd->prot_sdb;
+ int ivecs, count;
+
+ BUG_ON(prot_sdb == NULL);
+ ivecs = blk_rq_count_integrity_sg(cmd->request);
+
+ if (scsi_alloc_sgtable(prot_sdb, ivecs, gfp_mask)) {
+ error = BLKPREP_DEFER;
+ goto err_exit;
+ }
+
+ count = blk_rq_map_integrity_sg(cmd->request,
+ prot_sdb->table.sgl);
+ BUG_ON(unlikely(count > ivecs));
+
+ cmd->prot_sdb = prot_sdb;
+ cmd->prot_sdb->table.nents = count;
+ }
+
return BLKPREP_OK ;
err_exit:
cmd->tag = req->tag;
cmd->request = req;
+ cmd->cmnd = req->cmd;
+
return cmd;
}
req->buffer = NULL;
}
- BUILD_BUG_ON(sizeof(req->cmd) > sizeof(cmd->cmnd));
- memcpy(cmd->cmnd, req->cmd, sizeof(cmd->cmnd));
cmd->cmd_len = req->cmd_len;
if (!req->data_len)
cmd->sc_data_direction = DMA_NONE;
cmd->transfersize = req->data_len;
cmd->allowed = req->retries;
- cmd->timeout_per_command = req->timeout;
return BLKPREP_OK;
}
EXPORT_SYMBOL(scsi_setup_blk_pc_cmnd);
if (ret != BLKPREP_OK)
return ret;
+
+ if (unlikely(sdev->scsi_dh_data && sdev->scsi_dh_data->scsi_dh
+ && sdev->scsi_dh_data->scsi_dh->prep_fn)) {
+ ret = sdev->scsi_dh_data->scsi_dh->prep_fn(sdev, req);
+ if (ret != BLKPREP_OK)
+ return ret;
+ }
+
/*
* Filesystem requests must transfer data.
*/
if (unlikely(!cmd))
return BLKPREP_DEFER;
+ memset(cmd->cmnd, 0, BLK_MAX_CDB);
return scsi_init_io(cmd, GFP_ATOMIC);
}
EXPORT_SYMBOL(scsi_setup_fs_cmnd);
break;
case SDEV_QUIESCE:
case SDEV_BLOCK:
+ case SDEV_CREATED_BLOCK:
/*
* If the devices is blocked we defer normal commands.
*/
static inline int scsi_dev_queue_ready(struct request_queue *q,
struct scsi_device *sdev)
{
- if (sdev->device_busy >= sdev->queue_depth)
- return 0;
if (sdev->device_busy == 0 && sdev->device_blocked) {
/*
* unblock after device_blocked iterates to zero
return 0;
}
}
- if (sdev->device_blocked)
+ if (scsi_device_is_busy(sdev))
return 0;
return 1;
}
+
+/*
+ * scsi_target_queue_ready: checks if there we can send commands to target
+ * @sdev: scsi device on starget to check.
+ *
+ * Called with the host lock held.
+ */
+static inline int scsi_target_queue_ready(struct Scsi_Host *shost,
+ struct scsi_device *sdev)
+{
+ struct scsi_target *starget = scsi_target(sdev);
+
+ if (starget->single_lun) {
+ if (starget->starget_sdev_user &&
+ starget->starget_sdev_user != sdev)
+ return 0;
+ starget->starget_sdev_user = sdev;
+ }
+
+ if (starget->target_busy == 0 && starget->target_blocked) {
+ /*
+ * unblock after target_blocked iterates to zero
+ */
+ if (--starget->target_blocked == 0) {
+ SCSI_LOG_MLQUEUE(3, starget_printk(KERN_INFO, starget,
+ "unblocking target at zero depth\n"));
+ } else {
+ blk_plug_device(sdev->request_queue);
+ return 0;
+ }
+ }
+
+ if (scsi_target_is_busy(starget)) {
+ if (list_empty(&sdev->starved_entry)) {
+ list_add_tail(&sdev->starved_entry,
+ &shost->starved_list);
+ return 0;
+ }
+ }
+
+ /* We're OK to process the command, so we can't be starved */
+ if (!list_empty(&sdev->starved_entry))
+ list_del_init(&sdev->starved_entry);
+ return 1;
+}
+
/*
* scsi_host_queue_ready: if we can send requests to shost, return 1 else
* return 0. We must end up running the queue again whenever 0 is
printk("scsi%d unblocking host at zero depth\n",
shost->host_no));
} else {
- blk_plug_device(q);
return 0;
}
}
- if ((shost->can_queue > 0 && shost->host_busy >= shost->can_queue) ||
- shost->host_blocked || shost->host_self_blocked) {
+ if (scsi_host_is_busy(shost)) {
if (list_empty(&sdev->starved_entry))
list_add_tail(&sdev->starved_entry, &shost->starved_list);
return 0;
}
/*
+ * Busy state exporting function for request stacking drivers.
+ *
+ * For efficiency, no lock is taken to check the busy state of
+ * shost/starget/sdev, since the returned value is not guaranteed and
+ * may be changed after request stacking drivers call the function,
+ * regardless of taking lock or not.
+ *
+ * When scsi can't dispatch I/Os anymore and needs to kill I/Os
+ * (e.g. !sdev), scsi needs to return 'not busy'.
+ * Otherwise, request stacking drivers may hold requests forever.
+ */
+static int scsi_lld_busy(struct request_queue *q)
+{
+ struct scsi_device *sdev = q->queuedata;
+ struct Scsi_Host *shost;
+ struct scsi_target *starget;
+
+ if (!sdev)
+ return 0;
+
+ shost = sdev->host;
+ starget = scsi_target(sdev);
+
+ if (scsi_host_in_recovery(shost) || scsi_host_is_busy(shost) ||
+ scsi_target_is_busy(starget) || scsi_device_is_busy(sdev))
+ return 1;
+
+ return 0;
+}
+
+/*
* Kill a request for a dead device
*/
static void scsi_kill_request(struct request *req, struct request_queue *q)
{
struct scsi_cmnd *cmd = req->special;
struct scsi_device *sdev = cmd->device;
+ struct scsi_target *starget = scsi_target(sdev);
struct Scsi_Host *shost = sdev->host;
blkdev_dequeue_request(req);
if (unlikely(cmd == NULL)) {
printk(KERN_CRIT "impossible request in %s.\n",
- __FUNCTION__);
+ __func__);
BUG();
}
spin_unlock(sdev->request_queue->queue_lock);
spin_lock(shost->host_lock);
shost->host_busy++;
+ starget->target_busy++;
spin_unlock(shost->host_lock);
spin_lock(sdev->request_queue->queue_lock);
- __scsi_done(cmd);
+ blk_complete_request(req);
}
static void scsi_softirq_done(struct request *rq)
{
- struct scsi_cmnd *cmd = rq->completion_data;
- unsigned long wait_for = (cmd->allowed + 1) * cmd->timeout_per_command;
+ struct scsi_cmnd *cmd = rq->special;
+ unsigned long wait_for = (cmd->allowed + 1) * rq->timeout;
int disposition;
INIT_LIST_HEAD(&cmd->eh_entry);
+ /*
+ * Set the serial numbers back to zero
+ */
+ cmd->serial_number = 0;
+
+ atomic_inc(&cmd->device->iodone_cnt);
+ if (cmd->result)
+ atomic_inc(&cmd->device->ioerr_cnt);
+
disposition = scsi_decide_disposition(cmd);
if (disposition != SUCCESS &&
time_before(cmd->jiffies_at_alloc + wait_for, jiffies)) {
printk(KERN_CRIT "impossible request in %s.\n"
"please mail a stack trace to "
"linux-scsi@vger.kernel.org\n",
- __FUNCTION__);
+ __func__);
blk_dump_rq_flags(req, "foo");
BUG();
}
spin_lock(shost->host_lock);
- if (!scsi_host_queue_ready(q, shost, sdev))
+ /*
+ * We hit this when the driver is using a host wide
+ * tag map. For device level tag maps the queue_depth check
+ * in the device ready fn would prevent us from trying
+ * to allocate a tag. Since the map is a shared host resource
+ * we add the dev to the starved list so it eventually gets
+ * a run when a tag is freed.
+ */
+ if (blk_queue_tagged(q) && !blk_rq_tagged(req)) {
+ if (list_empty(&sdev->starved_entry))
+ list_add_tail(&sdev->starved_entry,
+ &shost->starved_list);
goto not_ready;
- if (scsi_target(sdev)->single_lun) {
- if (scsi_target(sdev)->starget_sdev_user &&
- scsi_target(sdev)->starget_sdev_user != sdev)
- goto not_ready;
- scsi_target(sdev)->starget_sdev_user = sdev;
}
+
+ if (!scsi_target_queue_ready(shost, sdev))
+ goto not_ready;
+
+ if (!scsi_host_queue_ready(q, shost, sdev))
+ goto not_ready;
+
+ scsi_target(sdev)->target_busy++;
shost->host_busy++;
/*
blk_queue_max_segment_size(q, dma_get_max_seg_size(dev));
+ /* New queue, no concurrency on queue_flags */
if (!shost->use_clustering)
- clear_bit(QUEUE_FLAG_CLUSTER, &q->queue_flags);
+ queue_flag_clear_unlocked(QUEUE_FLAG_CLUSTER, q);
/*
* set a reasonable default alignment on word boundaries: the
blk_queue_prep_rq(q, scsi_prep_fn);
blk_queue_softirq_done(q, scsi_softirq_done);
+ blk_queue_rq_timed_out(q, scsi_times_out);
+ blk_queue_lld_busy(q, scsi_lld_busy);
return q;
}
return -ENOMEM;
}
- scsi_bidi_sdb_cache = kmem_cache_create("scsi_bidi_sdb",
- sizeof(struct scsi_data_buffer),
- 0, 0, NULL);
- if (!scsi_bidi_sdb_cache) {
- printk(KERN_ERR "SCSI: can't init scsi bidi sdb cache\n");
+ scsi_sdb_cache = kmem_cache_create("scsi_data_buffer",
+ sizeof(struct scsi_data_buffer),
+ 0, 0, NULL);
+ if (!scsi_sdb_cache) {
+ printk(KERN_ERR "SCSI: can't init scsi sdb cache\n");
goto cleanup_io_context;
}
if (!sgp->slab) {
printk(KERN_ERR "SCSI: can't init sg slab %s\n",
sgp->name);
- goto cleanup_bidi_sdb;
+ goto cleanup_sdb;
}
sgp->pool = mempool_create_slab_pool(SG_MEMPOOL_SIZE,
if (!sgp->pool) {
printk(KERN_ERR "SCSI: can't init sg mempool %s\n",
sgp->name);
- goto cleanup_bidi_sdb;
+ goto cleanup_sdb;
}
}
return 0;
-cleanup_bidi_sdb:
+cleanup_sdb:
for (i = 0; i < SG_MEMPOOL_NR; i++) {
struct scsi_host_sg_pool *sgp = scsi_sg_pools + i;
if (sgp->pool)
if (sgp->slab)
kmem_cache_destroy(sgp->slab);
}
- kmem_cache_destroy(scsi_bidi_sdb_cache);
+ kmem_cache_destroy(scsi_sdb_cache);
cleanup_io_context:
kmem_cache_destroy(scsi_io_context_cache);
int i;
kmem_cache_destroy(scsi_io_context_cache);
- kmem_cache_destroy(scsi_bidi_sdb_cache);
+ kmem_cache_destroy(scsi_sdb_cache);
for (i = 0; i < SG_MEMPOOL_NR; i++) {
struct scsi_host_sg_pool *sgp = scsi_sg_pools + i;
do {
result = scsi_execute_req(sdev, cmd, DMA_NONE, NULL, 0, sshdr,
timeout, retries);
- } while ((driver_byte(result) & DRIVER_SENSE) &&
- sshdr && sshdr->sense_key == UNIT_ATTENTION &&
- --retries);
+ if (sdev->removable && scsi_sense_valid(sshdr) &&
+ sshdr->sense_key == UNIT_ATTENTION)
+ sdev->changed = 1;
+ } while (scsi_sense_valid(sshdr) &&
+ sshdr->sense_key == UNIT_ATTENTION && --retries);
if (!sshdr)
/* could not allocate sense buffer, so can't process it */
return result;
- if ((driver_byte(result) & DRIVER_SENSE) && sdev->removable) {
-
- if ((scsi_sense_valid(sshdr)) &&
- ((sshdr->sense_key == UNIT_ATTENTION) ||
- (sshdr->sense_key == NOT_READY))) {
- sdev->changed = 1;
- result = 0;
- }
+ if (sdev->removable && scsi_sense_valid(sshdr) &&
+ (sshdr->sense_key == UNIT_ATTENTION ||
+ sshdr->sense_key == NOT_READY)) {
+ sdev->changed = 1;
+ result = 0;
}
if (!sshdr_external)
kfree(sshdr);
switch (state) {
case SDEV_CREATED:
- /* There are no legal states that come back to
- * created. This is the manually initialised start
- * state */
- goto illegal;
+ switch (oldstate) {
+ case SDEV_CREATED_BLOCK:
+ break;
+ default:
+ goto illegal;
+ }
+ break;
case SDEV_RUNNING:
switch (oldstate) {
case SDEV_BLOCK:
switch (oldstate) {
- case SDEV_CREATED:
case SDEV_RUNNING:
+ case SDEV_CREATED_BLOCK:
+ break;
+ default:
+ goto illegal;
+ }
+ break;
+
+ case SDEV_CREATED_BLOCK:
+ switch (oldstate) {
+ case SDEV_CREATED:
break;
default:
goto illegal;
int err = 0;
err = scsi_device_set_state(sdev, SDEV_BLOCK);
- if (err)
- return err;
+ if (err) {
+ err = scsi_device_set_state(sdev, SDEV_CREATED_BLOCK);
+
+ if (err)
+ return err;
+ }
/*
* The device has transitioned to SDEV_BLOCK. Stop the
* and goose the device queue if successful.
*/
err = scsi_device_set_state(sdev, SDEV_RUNNING);
- if (err)
- return err;
+ if (err) {
+ err = scsi_device_set_state(sdev, SDEV_CREATED);
+
+ if (err)
+ return err;
+ }
spin_lock_irqsave(q->queue_lock, flags);
blk_start_queue(q);
if (unlikely(i == sg_count)) {
printk(KERN_ERR "%s: Bytes in sg: %zu, requested offset %zu, "
"elements %d\n",
- __FUNCTION__, sg_len, *offset, sg_count);
+ __func__, sg_len, *offset, sg_count);
WARN_ON(1);
return NULL;
}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff