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| author | Tomas Henzl <thenzl@redhat.com> | 2014-07-09 17:21:01 +0530 |
|---|---|---|
| committer | Christoph Hellwig <hch@lst.de> | 2014-07-25 17:17:04 -0400 |
| commit | 646cdf0083e3d4a9b995f37b72c3c8a22d9307de (patch) | |
| tree | f0730421a40f2037a840489a8afdce0e4b2c1598 /drivers/scsi/pm8001/pm8001_sas.c | |
| parent | 5533abca06e07121697ed1d30863ce03e7c518e5 (diff) | |
| download | talos-op-linux-646cdf0083e3d4a9b995f37b72c3c8a22d9307de.tar.gz talos-op-linux-646cdf0083e3d4a9b995f37b72c3c8a22d9307de.zip | |
pm8001: add a new spinlock to protect the CCB
Patch adds a new spinlock to protect the ccb management.
It may happen that concurrent threads become the same tag value
from the 'alloc' function', the spinlock prevents this situation.
Signed-off-by: Tomas Henzl <thenzl@redhat.com>
Acked-by: Suresh Thiagarajan <Suresh.Thiagarajan@pmcs.com>
Acked-by: Jack Wang <xjtuwjp@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Diffstat (limited to 'drivers/scsi/pm8001/pm8001_sas.c')
| -rw-r--r-- | drivers/scsi/pm8001/pm8001_sas.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/drivers/scsi/pm8001/pm8001_sas.c b/drivers/scsi/pm8001/pm8001_sas.c index be55859042cd..34cea8291772 100644 --- a/drivers/scsi/pm8001/pm8001_sas.c +++ b/drivers/scsi/pm8001/pm8001_sas.c @@ -77,11 +77,16 @@ inline int pm8001_tag_alloc(struct pm8001_hba_info *pm8001_ha, u32 *tag_out) { unsigned int tag; void *bitmap = pm8001_ha->tags; + unsigned long flags; + spin_lock_irqsave(&pm8001_ha->bitmap_lock, flags); tag = find_first_zero_bit(bitmap, pm8001_ha->tags_num); - if (tag >= pm8001_ha->tags_num) + if (tag >= pm8001_ha->tags_num) { + spin_unlock_irqrestore(&pm8001_ha->bitmap_lock, flags); return -SAS_QUEUE_FULL; + } set_bit(tag, bitmap); + spin_unlock_irqrestore(&pm8001_ha->bitmap_lock, flags); *tag_out = tag; return 0; } |
