diff options
| author | Anton Blanchard | 2012-10-03 18:57:10 +0000 |
|---|---|---|
| committer | Benjamin Herrenschmidt | 2012-10-04 18:03:20 +1000 |
| commit | d900bd7366463fd96a907b2c212242e2b68b27d8 (patch) | |
| tree | b1837bc8c27d32a159ebc9edea9b1944e9231444 | |
| parent | c8adfeccee01ce3de6a7d14fcd4e3be02e27f03c (diff) | |
powerpc/iommu: Fix multiple issues with IOMMU pools code
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>
CC: <stable@kernel.org> [v3.6]
| -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 ff5a6ce027b8..8226c6cb348a 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 8ef63a01e345..bd968a43a48b 100644 --- a/arch/powerpc/sysdev/dart_iommu.c +++ b/arch/powerpc/sysdev/dart_iommu.c @@ -73,11 +73,16 @@ 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"); @@ -110,12 +115,17 @@ 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); @@ -137,6 +147,8 @@ 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) |