kernel/linux.git/lib/scatterlist.c, branch v3.18.135

lib/scatterlist: fix memory leak with scsi-mq

2014-10-28T16:27:10+00:00

Fix a memory leak with scsi-mq triggered by commands with large data transfer length. Fixes: c53c6d6a68b1 ("scatterlist: allow chaining to preallocated chunks") Cc: # 3.17.x Signed-off-by: Tony Battersby Reviewed-by: Martin K. Petersen Signed-off-by: Jens Axboe

lib/scatterlist: make ARCH_HAS_SG_CHAIN an actual Kconfig

2014-08-08T22:57:26+00:00

Rather than have architectures #define ARCH_HAS_SG_CHAIN in an architecture specific scatterlist.h, make it a proper Kconfig option and use that instead. At same time, remove the header files are are now mostly useless and just include asm-generic/scatterlist.h. [sfr@canb.auug.org.au: powerpc files now need asm/dma.h] Signed-off-by: Laura Abbott Acked-by: Thomas Gleixner [x86] Acked-by: Benjamin Herrenschmidt [powerpc] Acked-by: Heiko Carstens Cc: Russell King Cc: Tony Luck Cc: Fenghua Yu Cc: Paul Mackerras Cc: Ingo Molnar Cc: "H. Peter Anvin" Cc: "James E.J. Bottomley" Cc: Martin Schwidefsky Signed-off-by: Stephen Rothwell Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

scatterlist: allow chaining to preallocated chunks

2014-07-25T21:16:21+00:00

Blk-mq drivers usually preallocate their S/G list as part of the request, but if we want to support the very large S/G lists currently supported by the SCSI code that would tie up a lot of memory in the preallocated request pool. Add support to the scatterlist code so that it can initialize a S/G list that uses a preallocated first chunks and dynamically allocated additional chunks. That way the scsi-mq code can preallocate a first page worth of S/G entries as part of the request, and dynamically extend the S/G list when needed. Signed-off-by: Christoph Hellwig Reviewed-by: Martin K. Petersen Reviewed-by: Hannes Reinecke Reviewed-by: Webb Scales Acked-by: Jens Axboe Tested-by: Bart Van Assche Tested-by: Robert Elliott

lib/scatterlist: export sg_miter_skip()

2013-12-09T01:56:37+00:00

sg_copy_buffer() can't meet demand for some drrivers(such usb mass storage), so we have to use the sg_miter_* APIs to access sg buffer, then need export sg_miter_skip() for these drivers. The API is needed for converting to sg_miter_* APIs in USB storage driver for accessing sg buffer. Acked-by: Andrew Morton Cc: FUJITA Tomonori Cc: Jens Axboe Signed-off-by: Ming Lei Reviewed-by: Tejun Heo Signed-off-by: Greg Kroah-Hartman

lib/scatterlist.c: don't flush_kernel_dcache_page on slab page

2013-10-31T23:58:13+00:00

Commit b1adaf65ba03 ("[SCSI] block: add sg buffer copy helper functions") introduces two sg buffer copy helpers, and calls flush_kernel_dcache_page() on pages in SG list after these pages are written to. Unfortunately, the commit may introduce a potential bug: - Before sending some SCSI commands, kmalloc() buffer may be passed to block layper, so flush_kernel_dcache_page() can see a slab page finally - According to cachetlb.txt, flush_kernel_dcache_page() is only called on "a user page", which surely can't be a slab page. - ARCH's implementation of flush_kernel_dcache_page() may use page mapping information to do optimization so page_mapping() will see the slab page, then VM_BUG_ON() is triggered. Aaro Koskinen reported the bug on ARM/kirkwood when DEBUG_VM is enabled, and this patch fixes the bug by adding test of '!PageSlab(miter->page)' before calling flush_kernel_dcache_page(). Signed-off-by: Ming Lei Reported-by: Aaro Koskinen Tested-by: Simon Baatz Cc: Russell King - ARM Linux Cc: Will Deacon Cc: Aaro Koskinen Acked-by: Catalin Marinas Cc: FUJITA Tomonori Cc: Tejun Heo Cc: "James E.J. Bottomley" Cc: Jens Axboe Cc: [3.2+] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

lib/scatterlist: error handling in __sg_alloc_table()

2013-07-09T17:33:31+00:00

I was reviewing code which I suspected might allocate a zero size SG table. That will cause memory corruption. Also we can't return before doing the memset or we could end up using uninitialized memory in the cleanup path. Signed-off-by: Dan Carpenter Cc: Akinobu Mita Cc: Imre Deak Cc: Tejun Heo Cc: Daniel Vetter Cc: Maxim Levitsky Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

lib/scatterlist: introduce sg_pcopy_from_buffer() and sg_pcopy_to_buffer()

2013-07-09T17:33:30+00:00

The only difference between sg_pcopy_{from,to}_buffer() and sg_copy_{from,to}_buffer() is an additional argument that specifies the number of bytes to skip the SG list before copying. Signed-off-by: Akinobu Mita Cc: "David S. Miller" Cc: "James E.J. Bottomley" Cc: Douglas Gilbert Cc: Herbert Xu Cc: Horia Geanta Cc: Imre Deak Acked-by: Tejun Heo Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

lib/scatterlist: factor out sg_miter_get_next_page() from sg_miter_next()

2013-07-09T17:33:30+00:00

This patchset introduces sg_pcopy_from_buffer() and sg_pcopy_to_buffer(), which copy data between a linear buffer and an SG list. The only difference between sg_pcopy_{from,to}_buffer() and sg_copy_{from,to}_buffer() is an additional argument that specifies the number of bytes to skip the SG list before copying. The main reason for introducing these functions is to fix a problem in scsi_debug module. And there is a local function in crypto/talitos module, which can be replaced by sg_pcopy_to_buffer(). This patch: sg_miter_get_next_page() is used to proceed page iterator to the next page if necessary, and will be used to implement the variants of sg_copy_{from,to}_buffer() later. Signed-off-by: Akinobu Mita Acked-by: Tejun Heo Cc: Tejun Heo Cc: Imre Deak Cc: Herbert Xu Cc: "David S. Miller" Cc: "James E.J. Bottomley" Cc: Douglas Gilbert Cc: Horia Geanta Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

lib/scatterlist: sg_page_iter: support sg lists w/o backing pages

2013-03-27T16:13:44+00:00

The i915 driver uses sg lists for memory without backing 'struct page' pages, similarly to other IO memory regions, setting only the DMA address for these. It does this, so that it can program the HW MMU tables in a uniform way both for sg lists with and without backing pages. Without a valid page pointer we can't call nth_page to get the current page in __sg_page_iter_next, so add a helper that relevant users can call separately. Also add a helper to get the DMA address of the current page (idea from Daniel). Convert all places in i915, to use the new API. Signed-off-by: Imre Deak Reviewed-by: Damien Lespiau Signed-off-by: Daniel Vetter

lib/scatterlist: use page iterator in the mapping iterator

2013-02-28T03:10:10+00:00

For better code reuse use the newly added page iterator to iterate through the pages. The offset, length within the page is still calculated by the mapping iterator as well as the actual mapping. Idea from Tejun Heo. Signed-off-by: Imre Deak Cc: Maxim Levitsky Cc: Tejun Heo Cc: Daniel Vetter Cc: James Hogan Cc: Stephen Warren Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds