linux/lib/dma-debug.c, branch v2.6.32

dma-debug: Fix compile warning with PAE enabled

2009-10-29T15:25:50Z

When PAE is enabled in the kernel configuration the size of phys_addr_t differs from the size of a void pointer. The gcc prints a warning about that in dma-debug code. This patch fixes the warning by converting the output to unsigned long long instead of a pointer. Signed-off-by: Joerg Roedel

dma-debug: Fix check_unmap null pointer dereference

2009-08-21T08:04:24Z

While it's debatable whether or not a NULL device argument to the DMA API functions is valid... since it certainly isn't valid on devices with an IOMMU... dma-debug really shouldn't be dereferencing null pointers either. Guard against that in err_printk and the driver_filter functions. A Fedora rawhide user was seeing this in one of the dvb drivers resulting in an oops on boot. [ A patch has been sent for testing to the driver, but I feel the dma debugging support should be fixed as well. (There's still a pile of legacy garbage in the kernel passing null pointers to dma_{alloc,free}_*. :( ] Signed-off-by: Kyle McMartin Cc: mchehab@infradead.org Cc: Joerg Roedel LKML-Reference: <20090820011708.GP25206@bombadil.infradead.org> Signed-off-by: Ingo Molnar

dma-debug: Fix the overlap() function to be correct and readable

2009-07-10T20:18:45Z

Linus noticed how unclean and buggy the overlap() function is: - It uses convoluted (and bug-causing) positive checks for range overlap - instead of using a more natural negative check. - Even the positive checks are buggy: a positive intersection check has four natural cases while we checked only for three, missing the (addr < start && addr2 == end) case for example. - The variables are mis-named, making it non-obvious how the check was done. - It needlessly uses u64 instead of unsigned long. Since these are kernel memory pointers and we explicitly exclude highmem ranges anyway we cannot ever overflow 32 bits, even if we could. (and on 64-bit it doesnt matter anyway) All in one, this function needs a total revamp. I used Linus's suggestions minus the paranoid checks (we cannot overflow really because if we get totally bad DMA ranges passed far more things break in the systems than just DMA debugging). I also fixed a few other small details i noticed. Reported-by: Linus Torvalds Cc: Joerg Roedel Signed-off-by: Ingo Molnar

dma-debug: Put all hash-chain locks into the same lock class

2009-06-17T14:26:04Z

Alan Cox reported that lockdep runs out of its stack-trace entries with certain configs: BUG: MAX_STACK_TRACE_ENTRIES too low This happens because there are 1024 hash buckets, each with a separate lock. Lockdep puts each lock into a separate lock class and tracks them independently. But in reality we never take more than one of the buckets, so they really belong into a single lock-class. Annotate the has bucket lock init accordingly. [ Impact: reduce the lockdep footprint of dma-debug ] Reported-by: Alan Cox Signed-off-by: Ingo Molnar Signed-off-by: Joerg Roedel

dma-debug: fix off-by-one error in overlap function

2009-06-16T10:29:40Z

This patch fixes a bug in the overlap function which returned true if one region ends exactly before the second region begins. This is no overlap but the function returned true in that case. Cc: stable@kernel.org Reported-by: Andrew Randrianasulu Signed-off-by: Joerg Roedel

dma-debug: be more careful when building reference entries

2009-06-15T09:10:14Z

The current code is not very careful when it builds reference dma_debug_entries which get passed to hash_bucket_find(). But since this function changed to a best-fit algorithm these entries have to be more acurate. This patch adds this higher level of accuracy. Signed-off-by: Joerg Roedel

dma-debug: check for sg_call_ents in best-fit algorithm too

2009-06-15T09:08:54Z

If we don't check for sg_call_ents the hash_bucket_find function might still return the wrong dma_debug_entry for sg mappings. Signed-off-by: Joerg Roedel

dma-debug: simplify logic in driver_filter()

2009-06-08T13:53:46Z

This patch makes the driver_filter function more readable by reorganizing the code. The removal of a code code block to an upper indentation level makes hard-to-read line-wraps unnecessary. Signed-off-by: Joerg Roedel

dma-debug: disable/enable irqs only once in device_dma_allocations

2009-06-08T13:46:19Z

There is no need to disable/enable irqs on each loop iteration. Just disable irqs for the whole time the loop runs. Signed-off-by: Joerg Roedel

dma-debug: use pr_* instead of printk(KERN_* ...)

2009-06-08T13:39:24Z

The pr_* macros are shorter than the old printk(KERN_ ...) variant. Change the dma-debug code to use the new macros and save a few unnecessary line breaks. If lines don't break the source code can also be grepped more easily. Signed-off-by: Joerg Roedel