#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 {
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);
}
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
*
* 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)
*/
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
+ /* If the device is in the process of becoming
* ready, or has a temporary blockage, retry.
*/
if (sshdr.asc == 0x04) {
}
if (!(req->flags & REQ_QUIET)) {
scmd_printk(KERN_INFO, cmd,
- "Device not ready: ");
+ "Device not ready: ");
scsi_print_sense_hdr("", &sshdr);
}
scsi_end_request(cmd, 0, this_count, 1);
case VOLUME_OVERFLOW:
if (!(req->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)) {
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);
* 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)
* 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)) {
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:
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);