summaryrefslogtreecommitdiffstats
path: root/drivers/scsi/scsi_lib.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/scsi/scsi_lib.c')
-rw-r--r--drivers/scsi/scsi_lib.c142
1 files changed, 63 insertions, 79 deletions
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index faee4757c03a..3d04a9f386ac 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -19,18 +19,18 @@
#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 {
@@ -83,7 +83,7 @@ static void scsi_unprep_request(struct request *req)
struct scsi_cmnd *cmd = req->special;
req->flags &= ~REQ_DONTPREP;
- req->special = (req->flags & REQ_SPECIAL) ? cmd->sc_request : NULL;
+ req->special = NULL;
scsi_put_command(cmd);
}
@@ -161,72 +161,6 @@ int scsi_queue_insert(struct scsi_cmnd *cmd, int reason)
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
@@ -566,7 +500,7 @@ 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);
@@ -1300,15 +1234,7 @@ static int scsi_prep_fn(struct request_queue *q, struct request *req)
* at request->cmd, as this tells us the real story.
*/
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;
+ cmd = req->special;
} else if (req->flags & (REQ_CMD | REQ_BLOCK_PC)) {
if(unlikely(specials_only) && !(req->flags & REQ_SPECIAL)) {
@@ -2363,3 +2289,61 @@ scsi_target_unblock(struct device *dev)
device_for_each_child(dev, NULL, target_unblock);
}
EXPORT_SYMBOL_GPL(scsi_target_unblock);
+
+/**
+ * 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
+ *
+ * Returns virtual address of the start of the mapped page
+ */
+void *scsi_kmap_atomic_sg(struct scatterlist *sg, int sg_count,
+ size_t *offset, size_t *len)
+{
+ int i;
+ size_t sg_len = 0, len_complete = 0;
+ struct page *page;
+
+ for (i = 0; i < sg_count; i++) {
+ len_complete = sg_len; /* Complete sg-entries */
+ sg_len += sg[i].length;
+ if (sg_len > *offset)
+ break;
+ }
+
+ 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 NULL;
+ }
+
+ /* Offset starting from the beginning of first page in this sg-entry */
+ *offset = *offset - len_complete + sg[i].offset;
+
+ /* 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(scsi_kunmap_atomic_sg);