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| author | Bodo Stroesser <bstroesser@ts.fujitsu.com> | 2013-12-02 18:52:10 +0100 |
|---|---|---|
| committer | James Bottomley <JBottomley@Parallels.com> | 2013-12-19 20:56:28 -0800 |
| commit | 769989a4a09d7c825e182cf60604c06d8f2f70e4 (patch) | |
| tree | 273cb753047de8d2f10cd916acbabc8bc1587af6 /drivers/scsi | |
| parent | 762a86a901417280b2af9e2004f05d7481f30441 (diff) | |
| download | linux-769989a4a09d7c825e182cf60604c06d8f2f70e4.tar.gz linux-769989a4a09d7c825e182cf60604c06d8f2f70e4.tar.bz2 linux-769989a4a09d7c825e182cf60604c06d8f2f70e4.zip | |
[SCSI] st: fix enlarge_buffer
This patch removes a bug in enlarge_buffer() that can make a
read or write fail under special conditions.
After changing TRY_DIRECT_IO to 0 and ST_MAX_SG to 32 in
st_options.h, a program that writes a first block of 128k and
than a second bigger block (e.g. 256k) fails. The second write
returns errno EOVERFLOW, as enlarge_buffer() checks the sg list
and detects that it already is full.
As enlarge_buffer uses different page allocation orders
depending on the size of the buffer needed, the check does not
make sense.
Signed-off-by: Bodo Stroesser <bstroesser@ts.fujitsu.com>
Acked-by: Kai Mäkisara <kai.makisara@kolumbus.fi>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Diffstat (limited to 'drivers/scsi')
| -rw-r--r-- | drivers/scsi/st.c | 5 |
1 files changed, 1 insertions, 4 deletions
diff --git a/drivers/scsi/st.c b/drivers/scsi/st.c index ff44b3c2cff2..a1d6986261a3 100644 --- a/drivers/scsi/st.c +++ b/drivers/scsi/st.c @@ -3719,7 +3719,7 @@ static struct st_buffer *new_tape_buffer(int need_dma, int max_sg) static int enlarge_buffer(struct st_buffer * STbuffer, int new_size, int need_dma) { - int segs, nbr, max_segs, b_size, order, got; + int segs, max_segs, b_size, order, got; gfp_t priority; if (new_size <= STbuffer->buffer_size) @@ -3729,9 +3729,6 @@ static int enlarge_buffer(struct st_buffer * STbuffer, int new_size, int need_dm normalize_buffer(STbuffer); /* Avoid extra segment */ max_segs = STbuffer->use_sg; - nbr = max_segs - STbuffer->frp_segs; - if (nbr <= 0) - return 0; priority = GFP_KERNEL | __GFP_NOWARN; if (need_dma) |