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| author | Mike Christie <michaelc@cs.wisc.edu> | 2007-03-13 12:52:29 -0500 |
|---|---|---|
| committer | James Bottomley <jejb@mulgrave.localdomain> | 2007-10-12 14:38:17 -0400 |
| commit | bd441deaf341c524b28fd72831ebf6fef88f1c41 (patch) | |
| tree | f75f1170a90b55992a340c64e2ed52ecbfb19bce | |
| parent | 358147403d1506ee43335c152fa3864d90f5ef6e (diff) | |
| download | linux-bd441deaf341c524b28fd72831ebf6fef88f1c41.tar.gz linux-bd441deaf341c524b28fd72831ebf6fef88f1c41.tar.xz | |
[SCSI] fix write buffer length in scsi_req_map_sg()
sg's may have setup a the buffer with a different length than
the transfer length so we should be using the bufflen passed
in as the request's data len.
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
| -rw-r--r-- | drivers/scsi/scsi_lib.c | 14 |
1 files changed, 10 insertions, 4 deletions
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index a417a6ff9f97..277f1b64e9ac 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -301,7 +301,7 @@ static int scsi_req_map_sg(struct request *rq, struct scatterlist *sgl, { struct request_queue *q = rq->q; int nr_pages = (bufflen + sgl[0].offset + PAGE_SIZE - 1) >> PAGE_SHIFT; - unsigned int data_len = 0, len, bytes, off; + unsigned int data_len = bufflen, len, bytes, off; struct page *page; struct bio *bio = NULL; int i, err, nr_vecs = 0; @@ -310,10 +310,15 @@ static int scsi_req_map_sg(struct request *rq, struct scatterlist *sgl, page = sgl[i].page; off = sgl[i].offset; len = sgl[i].length; - data_len += len; - while (len > 0) { + while (len > 0 && data_len > 0) { + /* + * sg sends a scatterlist that is larger than + * the data_len it wants transferred for certain + * IO sizes + */ bytes = min_t(unsigned int, len, PAGE_SIZE - off); + bytes = min(bytes, data_len); if (!bio) { nr_vecs = min_t(int, BIO_MAX_PAGES, nr_pages); @@ -345,12 +350,13 @@ static int scsi_req_map_sg(struct request *rq, struct scatterlist *sgl, page++; len -= bytes; + data_len -=bytes; off = 0; } } rq->buffer = rq->data = NULL; - rq->data_len = data_len; + rq->data_len = bufflen; return 0; free_bios: |