diff options
author | Roland Dreier <rolandd@cisco.com> | 2006-08-31 16:43:06 -0700 |
---|---|---|
committer | Roland Dreier <rolandd@cisco.com> | 2006-08-31 17:25:56 -0700 |
commit | 5a4e6dccbc0cd1b726820b782daebf887dcb95e9 (patch) | |
tree | 28750ce9e633081f8e814d69a3f3d21fd71359f8 /drivers/infiniband | |
parent | 22db37ec5fd51b0c77b1dd5751b1cdc2672c08d6 (diff) |
IB/mthca: Use IRQ safe locks to protect allocation bitmaps
It is supposed to be OK to call mthca_create_ah() and mthca_destroy_ah()
from any context. However, for mem-full HCAs, these functions use the
mthca_alloc() and mthca_free() bitmap helpers, and those helpers use
non-IRQ-safe spin_lock() internally. Lockdep correctly warns that
this could lead to a deadlock. Fix this by changing mthca_alloc() and
mthca_free() to use spin_lock_irqsave().
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Diffstat (limited to 'drivers/infiniband')
-rw-r--r-- | drivers/infiniband/hw/mthca/mthca_allocator.c | 15 |
1 files changed, 11 insertions, 4 deletions
diff --git a/drivers/infiniband/hw/mthca/mthca_allocator.c b/drivers/infiniband/hw/mthca/mthca_allocator.c index 25157f57a6d0..f930e55b58fc 100644 --- a/drivers/infiniband/hw/mthca/mthca_allocator.c +++ b/drivers/infiniband/hw/mthca/mthca_allocator.c @@ -41,9 +41,11 @@ /* Trivial bitmap-based allocator */ u32 mthca_alloc(struct mthca_alloc *alloc) { + unsigned long flags; u32 obj; - spin_lock(&alloc->lock); + spin_lock_irqsave(&alloc->lock, flags); + obj = find_next_zero_bit(alloc->table, alloc->max, alloc->last); if (obj >= alloc->max) { alloc->top = (alloc->top + alloc->max) & alloc->mask; @@ -56,19 +58,24 @@ u32 mthca_alloc(struct mthca_alloc *alloc) } else obj = -1; - spin_unlock(&alloc->lock); + spin_unlock_irqrestore(&alloc->lock, flags); return obj; } void mthca_free(struct mthca_alloc *alloc, u32 obj) { + unsigned long flags; + obj &= alloc->max - 1; - spin_lock(&alloc->lock); + + spin_lock_irqsave(&alloc->lock, flags); + clear_bit(obj, alloc->table); alloc->last = min(alloc->last, obj); alloc->top = (alloc->top + alloc->max) & alloc->mask; - spin_unlock(&alloc->lock); + + spin_unlock_irqrestore(&alloc->lock, flags); } int mthca_alloc_init(struct mthca_alloc *alloc, u32 num, u32 mask, |