diff options
| author | Anton Blanchard <anton@samba.org> | 2012-10-03 18:57:10 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-10-13 05:50:17 +0900 |
| commit | 11464f790b08f7a8b0e5a98b994f53bd33ecb9e4 (patch) | |
| tree | 517480d28c88a219b327a3a6cd538d04d56f1e63 /arch | |
| parent | 987bb385ef97fba0dcaf531e63a9bc5ca2e2f9f1 (diff) | |
powerpc/iommu: Fix multiple issues with IOMMU pools code
commit d900bd7366463fd96a907b2c212242e2b68b27d8 upstream.
There are a number of issues in the recent IOMMU pools code:
- On a preempt kernel we might switch CPUs in the middle of building
a scatter gather list. When this happens the handle hint passed in
no longer falls within the local CPU's pool. Check for this and
fall back to the pool hint.
- We were missing a spin_unlock/spin_lock in one spot where we
switch pools.
- We need to provide locking around dart_tlb_invalidate_all and
dart_tlb_invalidate_one now that the global lock is gone.
Reported-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/powerpc/kernel/iommu.c | 5 | ||||
| -rw-r--r-- | arch/powerpc/sysdev/dart_iommu.c | 12 |
2 files changed, 16 insertions, 1 deletions
diff --git a/arch/powerpc/kernel/iommu.c b/arch/powerpc/kernel/iommu.c index ff5a6ce027b..8226c6cb348 100644 --- a/arch/powerpc/kernel/iommu.c +++ b/arch/powerpc/kernel/iommu.c @@ -215,7 +215,8 @@ static unsigned long iommu_range_alloc(struct device *dev, spin_lock_irqsave(&(pool->lock), flags); again: - if ((pass == 0) && handle && *handle) + if ((pass == 0) && handle && *handle && + (*handle >= pool->start) && (*handle < pool->end)) start = *handle; else start = pool->hint; @@ -236,7 +237,9 @@ again: * but on second pass, start at 0 in pool 0. */ if ((start & mask) >= limit || pass > 0) { + spin_unlock(&(pool->lock)); pool = &(tbl->pools[0]); + spin_lock(&(pool->lock)); start = pool->start; } else { start &= mask; diff --git a/arch/powerpc/sysdev/dart_iommu.c b/arch/powerpc/sysdev/dart_iommu.c index 4f2680f431b..b68b0db17b3 100644 --- a/arch/powerpc/sysdev/dart_iommu.c +++ b/arch/powerpc/sysdev/dart_iommu.c @@ -74,11 +74,16 @@ static int dart_is_u4; #define DBG(...) +static DEFINE_SPINLOCK(invalidate_lock); + static inline void dart_tlb_invalidate_all(void) { unsigned long l = 0; unsigned int reg, inv_bit; unsigned long limit; + unsigned long flags; + + spin_lock_irqsave(&invalidate_lock, flags); DBG("dart: flush\n"); @@ -111,12 +116,17 @@ retry: panic("DART: TLB did not flush after waiting a long " "time. Buggy U3 ?"); } + + spin_unlock_irqrestore(&invalidate_lock, flags); } static inline void dart_tlb_invalidate_one(unsigned long bus_rpn) { unsigned int reg; unsigned int l, limit; + unsigned long flags; + + spin_lock_irqsave(&invalidate_lock, flags); reg = DART_CNTL_U4_ENABLE | DART_CNTL_U4_IONE | (bus_rpn & DART_CNTL_U4_IONE_MASK); @@ -138,6 +148,8 @@ wait_more: panic("DART: TLB did not flush after waiting a long " "time. Buggy U4 ?"); } + + spin_unlock_irqrestore(&invalidate_lock, flags); } static void dart_flush(struct iommu_table *tbl) |