#include <linux/hardirq.h>
#include <scsi/scsi.h>
+#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_dbg.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_driver.h>
#include <scsi/scsi_eh.h>
#include <scsi/scsi_host.h>
-#include <scsi/scsi_request.h>
#include "scsi_priv.h"
#include "scsi_logging.h"
-#define SG_MEMPOOL_NR (sizeof(scsi_sg_pools)/sizeof(struct scsi_host_sg_pool))
+#define SG_MEMPOOL_NR ARRAY_SIZE(scsi_sg_pools)
#define SG_MEMPOOL_SIZE 32
struct scsi_host_sg_pool {
size_t size;
char *name;
- kmem_cache_t *slab;
+ struct kmem_cache *slab;
mempool_t *pool;
};
{
struct scsi_cmnd *cmd = req->special;
- req->flags &= ~REQ_DONTPREP;
- req->special = (req->flags & REQ_SPECIAL) ? cmd->sc_request : NULL;
+ req->cmd_flags &= ~REQ_DONTPREP;
+ req->special = NULL;
scsi_put_command(cmd);
}
return 0;
}
-/*
- * Function: scsi_do_req
- *
- * Purpose: Queue a SCSI request
- *
- * Arguments: sreq - command descriptor.
- * cmnd - actual SCSI command to be performed.
- * buffer - data buffer.
- * bufflen - size of data buffer.
- * done - completion function to be run.
- * timeout - how long to let it run before timeout.
- * retries - number of retries we allow.
- *
- * Lock status: No locks held upon entry.
- *
- * Returns: Nothing.
- *
- * Notes: This function is only used for queueing requests for things
- * like ioctls and character device requests - this is because
- * we essentially just inject a request into the queue for the
- * device.
- *
- * In order to support the scsi_device_quiesce function, we
- * now inject requests on the *head* of the device queue
- * rather than the tail.
- */
-void scsi_do_req(struct scsi_request *sreq, const void *cmnd,
- void *buffer, unsigned bufflen,
- void (*done)(struct scsi_cmnd *),
- int timeout, int retries)
-{
- /*
- * If the upper level driver is reusing these things, then
- * we should release the low-level block now. Another one will
- * be allocated later when this request is getting queued.
- */
- __scsi_release_request(sreq);
-
- /*
- * Our own function scsi_done (which marks the host as not busy,
- * disables the timeout counter, etc) will be called by us or by the
- * scsi_hosts[host].queuecommand() function needs to also call
- * the completion function for the high level driver.
- */
- memcpy(sreq->sr_cmnd, cmnd, sizeof(sreq->sr_cmnd));
- sreq->sr_bufflen = bufflen;
- sreq->sr_buffer = buffer;
- sreq->sr_allowed = retries;
- sreq->sr_done = done;
- sreq->sr_timeout_per_command = timeout;
-
- if (sreq->sr_cmd_len == 0)
- sreq->sr_cmd_len = COMMAND_SIZE(sreq->sr_cmnd[0]);
-
- /*
- * head injection *required* here otherwise quiesce won't work
- *
- * Because users of this function are apt to reuse requests with no
- * modification, we have to sanitise the request flags here
- */
- sreq->sr_request->flags &= ~REQ_DONTPREP;
- blk_insert_request(sreq->sr_device->request_queue, sreq->sr_request,
- 1, sreq);
-}
-EXPORT_SYMBOL(scsi_do_req);
-
/**
* scsi_execute - insert request and wait for the result
* @sdev: scsi device
req->sense_len = 0;
req->retries = retries;
req->timeout = timeout;
- req->flags |= flags | REQ_BLOCK_PC | REQ_SPECIAL | REQ_QUIET;
+ req->cmd_type = REQ_TYPE_BLOCK_PC;
+ req->cmd_flags |= flags | REQ_QUIET | REQ_PREEMPT;
/*
* head injection *required* here otherwise quiesce won't work
int result;
if (sshdr) {
- sense = kmalloc(SCSI_SENSE_BUFFERSIZE, GFP_NOIO);
+ sense = kzalloc(SCSI_SENSE_BUFFERSIZE, GFP_NOIO);
if (!sense)
return DRIVER_ERROR << 24;
- memset(sense, 0, SCSI_SENSE_BUFFERSIZE);
}
result = scsi_execute(sdev, cmd, data_direction, buffer, bufflen,
- sense, timeout, retries, 0);
+ sense, timeout, retries, 0);
if (sshdr)
scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, sshdr);
char sense[SCSI_SENSE_BUFFERSIZE];
};
-static kmem_cache_t *scsi_io_context_cache;
+static struct kmem_cache *scsi_io_context_cache;
static void scsi_end_async(struct request *req, int uptodate)
{
if (!rq->bio)
blk_rq_bio_prep(q, rq, bio);
- else if (!q->back_merge_fn(q, rq, bio))
+ else if (!ll_back_merge_fn(q, rq, bio))
return -EINVAL;
else {
rq->biotail->bi_next = bio;
rq->biotail = bio;
- rq->hard_nr_sectors += bio_sectors(bio);
- rq->nr_sectors = rq->hard_nr_sectors;
}
return 0;
req = blk_get_request(sdev->request_queue, write, gfp);
if (!req)
goto free_sense;
- req->flags |= REQ_BLOCK_PC | REQ_QUIET;
+ req->cmd_type = REQ_TYPE_BLOCK_PC;
+ req->cmd_flags |= REQ_QUIET;
if (use_sg)
err = scsi_req_map_sg(req, buffer, use_sg, bufflen, gfp);
free_req:
blk_put_request(req);
free_sense:
- kfree(sioc);
+ kmem_cache_free(scsi_io_context_cache, sioc);
return DRIVER_ERROR << 24;
}
EXPORT_SYMBOL_GPL(scsi_execute_async);
*
* Arguments: cmd - command that is ready to be queued.
*
- * Returns: Nothing
- *
* Notes: This function has the job of initializing a number of
* fields related to error handling. Typically this will
* be called once for each command, as required.
*/
-static int scsi_init_cmd_errh(struct scsi_cmnd *cmd)
+static void scsi_init_cmd_errh(struct scsi_cmnd *cmd)
{
cmd->serial_number = 0;
-
memset(cmd->sense_buffer, 0, sizeof cmd->sense_buffer);
-
if (cmd->cmd_len == 0)
cmd->cmd_len = COMMAND_SIZE(cmd->cmnd[0]);
-
- /*
- * We need saved copies of a number of fields - this is because
- * error handling may need to overwrite these with different values
- * to run different commands, and once error handling is complete,
- * we will need to restore these values prior to running the actual
- * command.
- */
- cmd->old_use_sg = cmd->use_sg;
- cmd->old_cmd_len = cmd->cmd_len;
- cmd->sc_old_data_direction = cmd->sc_data_direction;
- cmd->old_underflow = cmd->underflow;
- memcpy(cmd->data_cmnd, cmd->cmnd, sizeof(cmd->cmnd));
- cmd->buffer = cmd->request_buffer;
- cmd->bufflen = cmd->request_bufflen;
-
- return 1;
-}
-
-/*
- * Function: scsi_setup_cmd_retry()
- *
- * Purpose: Restore the command state for a retry
- *
- * Arguments: cmd - command to be restored
- *
- * Returns: Nothing
- *
- * Notes: Immediately prior to retrying a command, we need
- * to restore certain fields that we saved above.
- */
-void scsi_setup_cmd_retry(struct scsi_cmnd *cmd)
-{
- memcpy(cmd->cmnd, cmd->data_cmnd, sizeof(cmd->data_cmnd));
- cmd->request_buffer = cmd->buffer;
- cmd->request_bufflen = cmd->bufflen;
- cmd->use_sg = cmd->old_use_sg;
- cmd->cmd_len = cmd->old_cmd_len;
- cmd->sc_data_direction = cmd->sc_old_data_direction;
- cmd->underflow = cmd->old_underflow;
}
void scsi_device_unbusy(struct scsi_device *sdev)
spin_lock_irqsave(shost->host_lock, flags);
shost->host_busy--;
if (unlikely(scsi_host_in_recovery(shost) &&
- shost->host_failed))
+ (shost->host_failed || shost->host_eh_scheduled)))
scsi_eh_wakeup(shost);
spin_unlock(shost->host_lock);
spin_lock(sdev->request_queue->queue_lock);
list_del_init(&sdev->starved_entry);
spin_unlock_irqrestore(shost->host_lock, flags);
- blk_run_queue(sdev->request_queue);
+
+ 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);
spin_lock_irqsave(shost->host_lock, flags);
if (unlikely(!list_empty(&sdev->starved_entry)))
return NULL;
}
-static struct scatterlist *scsi_alloc_sgtable(struct scsi_cmnd *cmd, gfp_t gfp_mask)
+struct scatterlist *scsi_alloc_sgtable(struct scsi_cmnd *cmd, gfp_t gfp_mask)
{
struct scsi_host_sg_pool *sgp;
struct scatterlist *sgl;
return sgl;
}
-static void scsi_free_sgtable(struct scatterlist *sgl, int index)
+EXPORT_SYMBOL(scsi_alloc_sgtable);
+
+void scsi_free_sgtable(struct scatterlist *sgl, int index)
{
struct scsi_host_sg_pool *sgp;
mempool_free(sgl, sgp->pool);
}
+EXPORT_SYMBOL(scsi_free_sgtable);
+
/*
* Function: scsi_release_buffers()
*
*/
static void scsi_release_buffers(struct scsi_cmnd *cmd)
{
- struct request *req = cmd->request;
-
- /*
- * Free up any indirection buffers we allocated for DMA purposes.
- */
if (cmd->use_sg)
scsi_free_sgtable(cmd->request_buffer, cmd->sglist_len);
- else if (cmd->request_buffer != req->buffer)
- kfree(cmd->request_buffer);
/*
* Zero these out. They now point to freed memory, and it is
* dangerous to hang onto the pointers.
*/
- cmd->buffer = NULL;
- cmd->bufflen = 0;
cmd->request_buffer = NULL;
cmd->request_bufflen = 0;
}
* b) We can just use scsi_requeue_command() here. This would
* be used if we just wanted to retry, for example.
*/
-void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes,
- unsigned int block_bytes)
+void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes)
{
int result = cmd->result;
- int this_count = cmd->bufflen;
+ int this_count = cmd->request_bufflen;
request_queue_t *q = cmd->device->request_queue;
struct request *req = cmd->request;
int clear_errors = 1;
int sense_valid = 0;
int sense_deferred = 0;
- /*
- * Free up any indirection buffers we allocated for DMA purposes.
- * For the case of a READ, we need to copy the data out of the
- * bounce buffer and into the real buffer.
- */
- if (cmd->use_sg)
- scsi_free_sgtable(cmd->buffer, cmd->sglist_len);
- else if (cmd->buffer != req->buffer) {
- if (rq_data_dir(req) == READ) {
- unsigned long flags;
- char *to = bio_kmap_irq(req->bio, &flags);
- memcpy(to, cmd->buffer, cmd->bufflen);
- bio_kunmap_irq(to, &flags);
- }
- kfree(cmd->buffer);
- }
+ scsi_release_buffers(cmd);
if (result) {
sense_valid = scsi_command_normalize_sense(cmd, &sshdr);
if (sense_valid)
sense_deferred = scsi_sense_is_deferred(&sshdr);
}
+
if (blk_pc_request(req)) { /* SG_IO ioctl from block level */
req->errors = result;
if (result) {
req->data_len = cmd->resid;
}
- /*
- * Zero these out. They now point to freed memory, and it is
- * dangerous to hang onto the pointers.
- */
- cmd->buffer = NULL;
- cmd->bufflen = 0;
- cmd->request_buffer = NULL;
- cmd->request_bufflen = 0;
-
/*
* Next deal with any sectors which we were able to correctly
* handle.
*/
- if (good_bytes >= 0) {
- SCSI_LOG_HLCOMPLETE(1, printk("%ld sectors total, %d bytes done.\n",
- req->nr_sectors, good_bytes));
- SCSI_LOG_HLCOMPLETE(1, printk("use_sg is %d\n", cmd->use_sg));
+ SCSI_LOG_HLCOMPLETE(1, printk("%ld sectors total, "
+ "%d bytes done.\n",
+ req->nr_sectors, good_bytes));
+ SCSI_LOG_HLCOMPLETE(1, printk("use_sg is %d\n", cmd->use_sg));
- if (clear_errors)
- req->errors = 0;
- /*
- * If multiple sectors are requested in one buffer, then
- * they will have been finished off by the first command.
- * If not, then we have a multi-buffer command.
- *
- * If block_bytes != 0, it means we had a medium error
- * of some sort, and that we want to mark some number of
- * sectors as not uptodate. Thus we want to inhibit
- * requeueing right here - we will requeue down below
- * when we handle the bad sectors.
- */
+ if (clear_errors)
+ req->errors = 0;
- /*
- * If the command completed without error, then either
- * finish off the rest of the command, or start a new one.
- */
- if (scsi_end_request(cmd, 1, good_bytes, result == 0) == NULL)
- return;
- }
- /*
- * Now, if we were good little boys and girls, Santa left us a request
- * sense buffer. We can extract information from this, so we
- * can choose a block to remap, etc.
+ /* 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, 1, good_bytes, result == 0) == NULL)
+ return;
+
+ /* good_bytes = 0, or (inclusive) there were leftovers and
+ * result = 0, so scsi_end_request couldn't retry.
*/
if (sense_valid && !sense_deferred) {
switch (sshdr.sense_key) {
case UNIT_ATTENTION:
if (cmd->device->removable) {
- /* detected disc change. set a bit
+ /* Detected disc change. Set a bit
* and quietly refuse further access.
*/
cmd->device->changed = 1;
- scsi_end_request(cmd, 0,
- this_count, 1);
+ scsi_end_request(cmd, 0, this_count, 1);
return;
} else {
- /*
- * Must have been a power glitch, or a
- * bus reset. Could not have been a
- * media change, so we just retry the
- * request and see what happens.
- */
+ /* Must have been a power glitch, or a
+ * bus reset. Could not have been a
+ * media change, so we just retry the
+ * request and see what happens.
+ */
scsi_requeue_command(q, cmd);
return;
}
break;
case ILLEGAL_REQUEST:
- /*
- * If we had an ILLEGAL REQUEST returned, then we may
- * have performed an unsupported command. The only
- * thing this should be would be a ten byte read where
- * only a six byte read was supported. Also, on a
- * system where READ CAPACITY failed, we may have read
- * past the end of the disk.
- */
+ /* If we had an ILLEGAL REQUEST returned, then
+ * we may have performed an unsupported
+ * command. The only thing this should be
+ * would be a ten byte read where only a six
+ * byte read was supported. Also, on a system
+ * where READ CAPACITY failed, we may have
+ * read past the end of the disk.
+ */
if ((cmd->device->use_10_for_rw &&
sshdr.asc == 0x20 && sshdr.ascq == 0x00) &&
(cmd->cmnd[0] == READ_10 ||
cmd->cmnd[0] == WRITE_10)) {
cmd->device->use_10_for_rw = 0;
- /*
- * This will cause a retry with a 6-byte
- * command.
+ /* This will cause a retry with a
+ * 6-byte command.
*/
scsi_requeue_command(q, cmd);
- result = 0;
+ return;
} else {
scsi_end_request(cmd, 0, this_count, 1);
return;
}
break;
case NOT_READY:
- /*
- * If the device is in the process of becoming ready,
- * retry.
+ /* If the device is in the process of becoming
+ * ready, or has a temporary blockage, retry.
*/
- if (sshdr.asc == 0x04 && sshdr.ascq == 0x01) {
- scsi_requeue_command(q, cmd);
- return;
+ if (sshdr.asc == 0x04) {
+ switch (sshdr.ascq) {
+ case 0x01: /* becoming ready */
+ case 0x04: /* format in progress */
+ case 0x05: /* rebuild in progress */
+ case 0x06: /* recalculation in progress */
+ case 0x07: /* operation in progress */
+ case 0x08: /* Long write in progress */
+ case 0x09: /* self test in progress */
+ scsi_requeue_command(q, cmd);
+ return;
+ default:
+ break;
+ }
}
- if (!(req->flags & REQ_QUIET))
+ if (!(req->cmd_flags & REQ_QUIET)) {
scmd_printk(KERN_INFO, cmd,
- "Device not ready.\n");
+ "Device not ready: ");
+ scsi_print_sense_hdr("", &sshdr);
+ }
scsi_end_request(cmd, 0, this_count, 1);
return;
case VOLUME_OVERFLOW:
- if (!(req->flags & REQ_QUIET)) {
+ if (!(req->cmd_flags & REQ_QUIET)) {
scmd_printk(KERN_INFO, cmd,
- "Volume overflow, CDB: ");
- __scsi_print_command(cmd->data_cmnd);
+ "Volume overflow, CDB: ");
+ __scsi_print_command(cmd->cmnd);
scsi_print_sense("", cmd);
}
- scsi_end_request(cmd, 0, block_bytes, 1);
+ /* See SSC3rXX or current. */
+ scsi_end_request(cmd, 0, this_count, 1);
return;
default:
break;
}
- } /* driver byte != 0 */
+ }
if (host_byte(result) == DID_RESET) {
- /*
- * Third party bus reset or reset for error
- * recovery reasons. Just retry the request
- * and see what happens.
+ /* Third party bus reset or reset for error recovery
+ * reasons. Just retry the request and see what
+ * happens.
*/
scsi_requeue_command(q, cmd);
return;
}
if (result) {
- if (!(req->flags & REQ_QUIET)) {
+ if (!(req->cmd_flags & REQ_QUIET)) {
scmd_printk(KERN_INFO, cmd,
- "SCSI error: return code = 0x%x\n", result);
-
+ "SCSI error: return code = 0x%08x\n",
+ result);
if (driver_byte(result) & DRIVER_SENSE)
scsi_print_sense("", cmd);
}
- /*
- * Mark a single buffer as not uptodate. Queue the remainder.
- * We sometimes get this cruft in the event that a medium error
- * isn't properly reported.
- */
- block_bytes = req->hard_cur_sectors << 9;
- if (!block_bytes)
- block_bytes = req->data_len;
- scsi_end_request(cmd, 0, block_bytes, 1);
}
+ scsi_end_request(cmd, 0, this_count, !result);
}
EXPORT_SYMBOL(scsi_io_completion);
int count;
/*
- * if this is a rq->data based REQ_BLOCK_PC, setup for a non-sg xfer
- */
- if ((req->flags & REQ_BLOCK_PC) && !req->bio) {
- cmd->request_bufflen = req->data_len;
- cmd->request_buffer = req->data;
- req->buffer = req->data;
- cmd->use_sg = 0;
- return 0;
- }
-
- /*
- * we used to not use scatter-gather for single segment request,
+ * We used to not use scatter-gather for single segment request,
* but now we do (it makes highmem I/O easier to support without
* kmapping pages)
*/
cmd->use_sg = req->nr_phys_segments;
/*
- * if sg table allocation fails, requeue request later.
+ * If sg table allocation fails, requeue request later.
*/
sgpnt = scsi_alloc_sgtable(cmd, GFP_ATOMIC);
if (unlikely(!sgpnt)) {
return BLKPREP_DEFER;
}
+ req->buffer = NULL;
cmd->request_buffer = (char *) sgpnt;
- cmd->request_bufflen = req->nr_sectors << 9;
if (blk_pc_request(req))
cmd->request_bufflen = req->data_len;
- req->buffer = NULL;
+ else
+ cmd->request_bufflen = req->nr_sectors << 9;
/*
* Next, walk the list, and fill in the addresses and sizes of
* each segment.
*/
count = blk_rq_map_sg(req->q, req, cmd->request_buffer);
-
- /*
- * mapped well, send it off
- */
if (likely(count <= cmd->use_sg)) {
cmd->use_sg = count;
- return 0;
+ return BLKPREP_OK;
}
printk(KERN_ERR "Incorrect number of segments after building list\n");
return -EOPNOTSUPP;
}
+static struct scsi_cmnd *scsi_get_cmd_from_req(struct scsi_device *sdev,
+ struct request *req)
+{
+ struct scsi_cmnd *cmd;
+
+ if (!req->special) {
+ cmd = scsi_get_command(sdev, GFP_ATOMIC);
+ if (unlikely(!cmd))
+ return NULL;
+ req->special = cmd;
+ } else {
+ cmd = req->special;
+ }
+
+ /* pull a tag out of the request if we have one */
+ cmd->tag = req->tag;
+ cmd->request = req;
+
+ return cmd;
+}
+
static void scsi_blk_pc_done(struct scsi_cmnd *cmd)
{
BUG_ON(!blk_pc_request(cmd->request));
* successfully. Since this is a REQ_BLOCK_PC command the
* caller should check the request's errors value
*/
- scsi_io_completion(cmd, cmd->bufflen, 0);
+ scsi_io_completion(cmd, cmd->request_bufflen);
}
-static void scsi_setup_blk_pc_cmnd(struct scsi_cmnd *cmd)
+static int scsi_setup_blk_pc_cmnd(struct scsi_device *sdev, struct request *req)
{
- struct request *req = cmd->request;
+ struct scsi_cmnd *cmd;
+
+ cmd = scsi_get_cmd_from_req(sdev, req);
+ if (unlikely(!cmd))
+ return BLKPREP_DEFER;
+
+ /*
+ * BLOCK_PC requests may transfer data, in which case they must
+ * a bio attached to them. Or they might contain a SCSI command
+ * that does not transfer data, in which case they may optionally
+ * submit a request without an attached bio.
+ */
+ if (req->bio) {
+ int ret;
+
+ BUG_ON(!req->nr_phys_segments);
+
+ ret = scsi_init_io(cmd);
+ if (unlikely(ret))
+ return ret;
+ } else {
+ BUG_ON(req->data_len);
+ BUG_ON(req->data);
+
+ cmd->request_bufflen = 0;
+ cmd->request_buffer = NULL;
+ cmd->use_sg = 0;
+ req->buffer = NULL;
+ }
- BUG_ON(sizeof(req->cmd) > sizeof(cmd->cmnd));
+ 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->allowed = req->retries;
cmd->timeout_per_command = req->timeout;
cmd->done = scsi_blk_pc_done;
+ return BLKPREP_OK;
}
-static int scsi_prep_fn(struct request_queue *q, struct request *req)
+/*
+ * Setup a REQ_TYPE_FS command. These are simple read/write request
+ * from filesystems that still need to be translated to SCSI CDBs from
+ * the ULD.
+ */
+static int scsi_setup_fs_cmnd(struct scsi_device *sdev, struct request *req)
{
- struct scsi_device *sdev = q->queuedata;
struct scsi_cmnd *cmd;
- int specials_only = 0;
+ struct scsi_driver *drv;
+ int ret;
/*
- * Just check to see if the device is online. If it isn't, we
- * refuse to process any commands. The device must be brought
- * online before trying any recovery commands
+ * Filesystem requests must transfer data.
*/
- if (unlikely(!scsi_device_online(sdev))) {
- sdev_printk(KERN_ERR, sdev,
- "rejecting I/O to offline device\n");
- goto kill;
- }
- if (unlikely(sdev->sdev_state != SDEV_RUNNING)) {
- /* OK, we're not in a running state don't prep
- * user commands */
- if (sdev->sdev_state == SDEV_DEL) {
- /* Device is fully deleted, no commands
- * at all allowed down */
- sdev_printk(KERN_ERR, sdev,
- "rejecting I/O to dead device\n");
- goto kill;
- }
- /* OK, we only allow special commands (i.e. not
- * user initiated ones */
- specials_only = sdev->sdev_state;
- }
+ BUG_ON(!req->nr_phys_segments);
+
+ cmd = scsi_get_cmd_from_req(sdev, req);
+ if (unlikely(!cmd))
+ return BLKPREP_DEFER;
+
+ ret = scsi_init_io(cmd);
+ if (unlikely(ret))
+ return ret;
/*
- * Find the actual device driver associated with this command.
- * The SPECIAL requests are things like character device or
- * ioctls, which did not originate from ll_rw_blk. Note that
- * the special field is also used to indicate the cmd for
- * the remainder of a partially fulfilled request that can
- * come up when there is a medium error. We have to treat
- * these two cases differently. We differentiate by looking
- * at request->cmd, as this tells us the real story.
+ * Initialize the actual SCSI command for this request.
*/
- if (req->flags & REQ_SPECIAL && req->special) {
- struct scsi_request *sreq = req->special;
-
- if (sreq->sr_magic == SCSI_REQ_MAGIC) {
- cmd = scsi_get_command(sreq->sr_device, GFP_ATOMIC);
- if (unlikely(!cmd))
- goto defer;
- scsi_init_cmd_from_req(cmd, sreq);
- } else
- cmd = req->special;
- } else if (req->flags & (REQ_CMD | REQ_BLOCK_PC)) {
+ drv = *(struct scsi_driver **)req->rq_disk->private_data;
+ if (unlikely(!drv->init_command(cmd))) {
+ scsi_release_buffers(cmd);
+ scsi_put_command(cmd);
+ return BLKPREP_KILL;
+ }
- if(unlikely(specials_only) && !(req->flags & REQ_SPECIAL)) {
- if(specials_only == SDEV_QUIESCE ||
- specials_only == SDEV_BLOCK)
- goto defer;
-
+ return BLKPREP_OK;
+}
+
+static int scsi_prep_fn(struct request_queue *q, struct request *req)
+{
+ struct scsi_device *sdev = q->queuedata;
+ int ret = BLKPREP_OK;
+
+ /*
+ * If the device is not in running state we will reject some
+ * or all commands.
+ */
+ if (unlikely(sdev->sdev_state != SDEV_RUNNING)) {
+ switch (sdev->sdev_state) {
+ case SDEV_OFFLINE:
+ /*
+ * If the device is offline we refuse to process any
+ * commands. The device must be brought online
+ * before trying any recovery commands.
+ */
sdev_printk(KERN_ERR, sdev,
- "rejecting I/O to device being removed\n");
- goto kill;
+ "rejecting I/O to offline device\n");
+ ret = BLKPREP_KILL;
+ break;
+ case SDEV_DEL:
+ /*
+ * If the device is fully deleted, we refuse to
+ * process any commands as well.
+ */
+ sdev_printk(KERN_ERR, sdev,
+ "rejecting I/O to dead device\n");
+ ret = BLKPREP_KILL;
+ break;
+ case SDEV_QUIESCE:
+ case SDEV_BLOCK:
+ /*
+ * If the devices is blocked we defer normal commands.
+ */
+ if (!(req->cmd_flags & REQ_PREEMPT))
+ ret = BLKPREP_DEFER;
+ break;
+ default:
+ /*
+ * For any other not fully online state we only allow
+ * special commands. In particular any user initiated
+ * command is not allowed.
+ */
+ if (!(req->cmd_flags & REQ_PREEMPT))
+ ret = BLKPREP_KILL;
+ break;
}
-
-
- /*
- * Now try and find a command block that we can use.
- */
- if (!req->special) {
- cmd = scsi_get_command(sdev, GFP_ATOMIC);
- if (unlikely(!cmd))
- goto defer;
- } else
- cmd = req->special;
-
- /* pull a tag out of the request if we have one */
- cmd->tag = req->tag;
- } else {
- blk_dump_rq_flags(req, "SCSI bad req");
- goto kill;
+
+ if (ret != BLKPREP_OK)
+ goto out;
}
-
- /* note the overloading of req->special. When the tag
- * is active it always means cmd. If the tag goes
- * back for re-queueing, it may be reset */
- req->special = cmd;
- cmd->request = req;
-
- /*
- * FIXME: drop the lock here because the functions below
- * expect to be called without the queue lock held. Also,
- * previously, we dequeued the request before dropping the
- * lock. We hope REQ_STARTED prevents anything untoward from
- * happening now.
- */
- if (req->flags & (REQ_CMD | REQ_BLOCK_PC)) {
- int ret;
+ switch (req->cmd_type) {
+ case REQ_TYPE_BLOCK_PC:
+ ret = scsi_setup_blk_pc_cmnd(sdev, req);
+ break;
+ case REQ_TYPE_FS:
+ ret = scsi_setup_fs_cmnd(sdev, req);
+ break;
+ default:
/*
- * This will do a couple of things:
- * 1) Fill in the actual SCSI command.
- * 2) Fill in any other upper-level specific fields
- * (timeout).
+ * All other command types are not supported.
*
- * If this returns 0, it means that the request failed
- * (reading past end of disk, reading offline device,
- * etc). This won't actually talk to the device, but
- * some kinds of consistency checking may cause the
- * request to be rejected immediately.
+ * Note that these days the SCSI subsystem does not use
+ * REQ_TYPE_SPECIAL requests anymore. These are only used
+ * (directly or via blk_insert_request) by non-SCSI drivers.
*/
+ blk_dump_rq_flags(req, "SCSI bad req");
+ ret = BLKPREP_KILL;
+ break;
+ }
- /*
- * This sets up the scatter-gather table (allocating if
- * required).
- */
- ret = scsi_init_io(cmd);
- switch(ret) {
- /* For BLKPREP_KILL/DEFER the cmd was released */
- case BLKPREP_KILL:
- goto kill;
- case BLKPREP_DEFER:
- goto defer;
- }
-
+ out:
+ switch (ret) {
+ case BLKPREP_KILL:
+ req->errors = DID_NO_CONNECT << 16;
+ break;
+ case BLKPREP_DEFER:
/*
- * Initialize the actual SCSI command for this request.
+ * If we defer, the elv_next_request() returns NULL, but the
+ * queue must be restarted, so we plug here if no returning
+ * command will automatically do that.
*/
- if (req->flags & REQ_BLOCK_PC) {
- scsi_setup_blk_pc_cmnd(cmd);
- } else if (req->rq_disk) {
- struct scsi_driver *drv;
-
- drv = *(struct scsi_driver **)req->rq_disk->private_data;
- if (unlikely(!drv->init_command(cmd))) {
- scsi_release_buffers(cmd);
- scsi_put_command(cmd);
- goto kill;
- }
- }
+ if (sdev->device_busy == 0)
+ blk_plug_device(q);
+ break;
+ default:
+ req->cmd_flags |= REQ_DONTPREP;
}
- /*
- * The request is now prepped, no need to come back here
- */
- req->flags |= REQ_DONTPREP;
- return BLKPREP_OK;
-
- defer:
- /* If we defer, the elv_next_request() returns NULL, but the
- * queue must be restarted, so we plug here if no returning
- * command will automatically do that. */
- if (sdev->device_busy == 0)
- blk_plug_device(q);
- return BLKPREP_DEFER;
- kill:
- req->errors = DID_NO_CONNECT << 16;
- return BLKPREP_KILL;
+ return ret;
}
/*
static void scsi_kill_request(struct request *req, request_queue_t *q)
{
struct scsi_cmnd *cmd = req->special;
+ struct scsi_device *sdev = cmd->device;
+ struct Scsi_Host *shost = sdev->host;
blkdev_dequeue_request(req);
scsi_init_cmd_errh(cmd);
cmd->result = DID_NO_CONNECT << 16;
atomic_inc(&cmd->device->iorequest_cnt);
+
+ /*
+ * SCSI request completion path will do scsi_device_unbusy(),
+ * bump busy counts. To bump the counters, we need to dance
+ * with the locks as normal issue path does.
+ */
+ sdev->device_busy++;
+ spin_unlock(sdev->request_queue->queue_lock);
+ spin_lock(shost->host_lock);
+ shost->host_busy++;
+ spin_unlock(shost->host_lock);
+ spin_lock(sdev->request_queue->queue_lock);
+
__scsi_done(cmd);
}
if (unlikely(cmd == NULL)) {
printk(KERN_CRIT "impossible request in %s.\n"
"please mail a stack trace to "
- "linux-scsi@vger.kernel.org",
+ "linux-scsi@vger.kernel.org\n",
__FUNCTION__);
+ blk_dump_rq_flags(req, "foo");
BUG();
}
spin_lock(shost->host_lock);
}
EXPORT_SYMBOL(scsi_calculate_bounce_limit);
-struct request_queue *scsi_alloc_queue(struct scsi_device *sdev)
+struct request_queue *__scsi_alloc_queue(struct Scsi_Host *shost,
+ request_fn_proc *request_fn)
{
- struct Scsi_Host *shost = sdev->host;
struct request_queue *q;
- q = blk_init_queue(scsi_request_fn, NULL);
+ q = blk_init_queue(request_fn, NULL);
if (!q)
return NULL;
- blk_queue_prep_rq(q, scsi_prep_fn);
-
blk_queue_max_hw_segments(q, shost->sg_tablesize);
blk_queue_max_phys_segments(q, SCSI_MAX_PHYS_SEGMENTS);
blk_queue_max_sectors(q, shost->max_sectors);
blk_queue_bounce_limit(q, scsi_calculate_bounce_limit(shost));
blk_queue_segment_boundary(q, shost->dma_boundary);
- blk_queue_issue_flush_fn(q, scsi_issue_flush_fn);
- blk_queue_softirq_done(q, scsi_softirq_done);
if (!shost->use_clustering)
clear_bit(QUEUE_FLAG_CLUSTER, &q->queue_flags);
return q;
}
+EXPORT_SYMBOL(__scsi_alloc_queue);
+
+struct request_queue *scsi_alloc_queue(struct scsi_device *sdev)
+{
+ struct request_queue *q;
+
+ q = __scsi_alloc_queue(sdev->host, scsi_request_fn);
+ if (!q)
+ return NULL;
+
+ blk_queue_prep_rq(q, scsi_prep_fn);
+ blk_queue_issue_flush_fn(q, scsi_issue_flush_fn);
+ blk_queue_softirq_done(q, scsi_softirq_done);
+ return q;
+}
void scsi_free_queue(struct request_queue *q)
{
sgp->name);
}
- sgp->pool = mempool_create(SG_MEMPOOL_SIZE,
- mempool_alloc_slab, mempool_free_slab,
- sgp->slab);
+ sgp->pool = mempool_create_slab_pool(SG_MEMPOOL_SIZE,
+ sgp->slab);
if (!sgp->pool) {
printk(KERN_ERR "SCSI: can't init sg mempool %s\n",
sgp->name);
kmem_cache_destroy(sgp->slab);
}
}
+
+/**
+ * scsi_mode_select - issue a mode select
+ * @sdev: SCSI device to be queried
+ * @pf: Page format bit (1 == standard, 0 == vendor specific)
+ * @sp: Save page bit (0 == don't save, 1 == save)
+ * @modepage: mode page being requested
+ * @buffer: request buffer (may not be smaller than eight bytes)
+ * @len: length of request buffer.
+ * @timeout: command timeout
+ * @retries: number of retries before failing
+ * @data: returns a structure abstracting the mode header data
+ * @sense: place to put sense data (or NULL if no sense to be collected).
+ * must be SCSI_SENSE_BUFFERSIZE big.
+ *
+ * Returns zero if successful; negative error number or scsi
+ * status on error
+ *
+ */
+int
+scsi_mode_select(struct scsi_device *sdev, int pf, int sp, int modepage,
+ unsigned char *buffer, int len, int timeout, int retries,
+ struct scsi_mode_data *data, struct scsi_sense_hdr *sshdr)
+{
+ unsigned char cmd[10];
+ unsigned char *real_buffer;
+ int ret;
+
+ memset(cmd, 0, sizeof(cmd));
+ cmd[1] = (pf ? 0x10 : 0) | (sp ? 0x01 : 0);
+
+ if (sdev->use_10_for_ms) {
+ if (len > 65535)
+ return -EINVAL;
+ real_buffer = kmalloc(8 + len, GFP_KERNEL);
+ if (!real_buffer)
+ return -ENOMEM;
+ memcpy(real_buffer + 8, buffer, len);
+ len += 8;
+ real_buffer[0] = 0;
+ real_buffer[1] = 0;
+ real_buffer[2] = data->medium_type;
+ real_buffer[3] = data->device_specific;
+ real_buffer[4] = data->longlba ? 0x01 : 0;
+ real_buffer[5] = 0;
+ real_buffer[6] = data->block_descriptor_length >> 8;
+ real_buffer[7] = data->block_descriptor_length;
+
+ cmd[0] = MODE_SELECT_10;
+ cmd[7] = len >> 8;
+ cmd[8] = len;
+ } else {
+ if (len > 255 || data->block_descriptor_length > 255 ||
+ data->longlba)
+ return -EINVAL;
+
+ real_buffer = kmalloc(4 + len, GFP_KERNEL);
+ if (!real_buffer)
+ return -ENOMEM;
+ memcpy(real_buffer + 4, buffer, len);
+ len += 4;
+ real_buffer[0] = 0;
+ real_buffer[1] = data->medium_type;
+ real_buffer[2] = data->device_specific;
+ real_buffer[3] = data->block_descriptor_length;
+
+
+ cmd[0] = MODE_SELECT;
+ cmd[4] = len;
+ }
+
+ ret = scsi_execute_req(sdev, cmd, DMA_TO_DEVICE, real_buffer, len,
+ sshdr, timeout, retries);
+ kfree(real_buffer);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(scsi_mode_select);
+
/**
* scsi_mode_sense - issue a mode sense, falling back from 10 to
* six bytes if necessary.
int
scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage,
unsigned char *buffer, int len, int timeout, int retries,
- struct scsi_mode_data *data, struct scsi_sense_hdr *sshdr) {
+ struct scsi_mode_data *data, struct scsi_sense_hdr *sshdr)
+{
unsigned char cmd[12];
int use_10_for_ms;
int header_length;
}
if(scsi_status_is_good(result)) {
- data->header_length = header_length;
- if(use_10_for_ms) {
+ if (unlikely(buffer[0] == 0x86 && buffer[1] == 0x0b &&
+ (modepage == 6 || modepage == 8))) {
+ /* Initio breakage? */
+ header_length = 0;
+ data->length = 13;
+ data->medium_type = 0;
+ data->device_specific = 0;
+ data->longlba = 0;
+ data->block_descriptor_length = 0;
+ } else if(use_10_for_ms) {
data->length = buffer[0]*256 + buffer[1] + 2;
data->medium_type = buffer[2];
data->device_specific = buffer[3];
data->device_specific = buffer[2];
data->block_descriptor_length = buffer[3];
}
+ data->header_length = header_length;
}
return result;
switch (oldstate) {
case SDEV_CREATED:
case SDEV_RUNNING:
+ case SDEV_QUIESCE:
case SDEV_OFFLINE:
case SDEV_BLOCK:
break;
case SDEV_DEL:
switch (oldstate) {
+ case SDEV_CREATED:
+ case SDEV_RUNNING:
+ case SDEV_OFFLINE:
case SDEV_CANCEL:
break;
default:
}
EXPORT_SYMBOL_GPL(scsi_target_unblock);
-
-struct work_queue_work {
- struct work_struct work;
- void (*fn)(void *);
- void *data;
-};
-
-static void execute_in_process_context_work(void *data)
-{
- void (*fn)(void *data);
- struct work_queue_work *wqw = data;
-
- fn = wqw->fn;
- data = wqw->data;
-
- kfree(wqw);
-
- fn(data);
-}
-
/**
- * scsi_execute_in_process_context - reliably execute the routine with user context
- * @fn: the function to execute
- * @data: data to pass to the function
+ * scsi_kmap_atomic_sg - find and atomically map an sg-elemnt
+ * @sg: scatter-gather list
+ * @sg_count: number of segments in sg
+ * @offset: offset in bytes into sg, on return offset into the mapped area
+ * @len: bytes to map, on return number of bytes mapped
*
- * Executes the function immediately if process context is available,
- * otherwise schedules the function for delayed execution.
- *
- * Returns: 0 - function was executed
- * 1 - function was scheduled for execution
- * <0 - error
+ * Returns virtual address of the start of the mapped page
*/
-int scsi_execute_in_process_context(void (*fn)(void *data), void *data)
+void *scsi_kmap_atomic_sg(struct scatterlist *sg, int sg_count,
+ size_t *offset, size_t *len)
{
- struct work_queue_work *wqw;
+ int i;
+ size_t sg_len = 0, len_complete = 0;
+ struct page *page;
- if (!in_interrupt()) {
- fn(data);
- return 0;
+ for (i = 0; i < sg_count; i++) {
+ len_complete = sg_len; /* Complete sg-entries */
+ sg_len += sg[i].length;
+ if (sg_len > *offset)
+ break;
}
- wqw = kmalloc(sizeof(struct work_queue_work), GFP_ATOMIC);
-
- if (unlikely(!wqw)) {
- printk(KERN_ERR "Failed to allocate memory\n");
+ 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);
WARN_ON(1);
- return -ENOMEM;
+ return NULL;
}
- INIT_WORK(&wqw->work, execute_in_process_context_work, wqw);
- wqw->fn = fn;
- wqw->data = data;
- schedule_work(&wqw->work);
+ /* Offset starting from the beginning of first page in this sg-entry */
+ *offset = *offset - len_complete + sg[i].offset;
- return 1;
+ /* Assumption: contiguous pages can be accessed as "page + i" */
+ page = nth_page(sg[i].page, (*offset >> PAGE_SHIFT));
+ *offset &= ~PAGE_MASK;
+
+ /* Bytes in this sg-entry from *offset to the end of the page */
+ sg_len = PAGE_SIZE - *offset;
+ if (*len > sg_len)
+ *len = sg_len;
+
+ return kmap_atomic(page, KM_BIO_SRC_IRQ);
+}
+EXPORT_SYMBOL(scsi_kmap_atomic_sg);
+
+/**
+ * scsi_kunmap_atomic_sg - atomically unmap a virtual address, previously
+ * mapped with scsi_kmap_atomic_sg
+ * @virt: virtual address to be unmapped
+ */
+void scsi_kunmap_atomic_sg(void *virt)
+{
+ kunmap_atomic(virt, KM_BIO_SRC_IRQ);
}
-EXPORT_SYMBOL_GPL(scsi_execute_in_process_context);
+EXPORT_SYMBOL(scsi_kunmap_atomic_sg);
git://git.onelab.eu / linux-2.6.git / blobdiff