scsi: revert "[SCSI] Get rid of scsi_cmnd->done"

This reverts commit 6f5391c283d7fdcf24bf40786ea79061919d1e1d ("[SCSI]
Get rid of scsi_cmnd->done") that was supposed to be a cleanup commit,
but apparently it causes regressions:

  Bug 9370 - v2.6.24-rc2-409-g9418d5d: attempt to access beyond end of device
  http://bugzilla.kernel.org/show_bug.cgi?id=9370

this patch should be reintroduced in a more split-up form to make
testing of it easier.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Matthew Wilcox <matthew@wil.cx>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 14 insertions, 0 deletions

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 0e81e4c..8df8267 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -1092,6 +1092,7 @@ void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes)
 	}
 	scsi_end_request(cmd, 0, this_count, !result);
 }
+EXPORT_SYMBOL(scsi_io_completion);
 
 /*
  * Function:    scsi_init_io()
@@ -1170,6 +1171,18 @@ static struct scsi_cmnd *scsi_get_cmd_from_req(struct scsi_device *sdev,
 	return cmd;
 }
 
+static void scsi_blk_pc_done(struct scsi_cmnd *cmd)
+{
+	BUG_ON(!blk_pc_request(cmd->request));
+	/*
+	 * This will complete the whole command with uptodate=1 so
+	 * as far as the block layer is concerned the command completed
+	 * successfully. Since this is a REQ_BLOCK_PC command the
+	 * caller should check the request's errors value
+	 */
+	scsi_io_completion(cmd, cmd->request_bufflen);
+}
+
 int scsi_setup_blk_pc_cmnd(struct scsi_device *sdev, struct request *req)
 {
 	struct scsi_cmnd *cmd;
@@ -1219,6 +1232,7 @@ int scsi_setup_blk_pc_cmnd(struct scsi_device *sdev, struct request *req)
 	cmd->transfersize = req->data_len;
 	cmd->allowed = req->retries;
 	cmd->timeout_per_command = req->timeout;
+	cmd->done = scsi_blk_pc_done;
 	return BLKPREP_OK;
 }
 EXPORT_SYMBOL(scsi_setup_blk_pc_cmnd);