kernel/linux.git/block/blk-map.c, branch linux-2.6.28.y

When block layer fails to map iov, it calls bio_unmap_user to undo

2008-12-03T11:41:20+00:00

mapping. Which is good if pages were mapped - but if they were provided by someone else and just copied then bad things happen - pages are released once here, and once by caller, leading to user triggerable BUG at include/linux/mm.h:246. Signed-off-by: Petr Vandrovec Signed-off-by: Jens Axboe

block: hold extra reference to bio in blk_rq_map_user_iov()

2008-11-18T14:08:56+00:00

If the size passed in is OK but we end up mapping too many segments, we call the unmap path directly like from IO completion. But from IO completion we have an extra reference to the bio, so this error case goes OOPS when it attempts to free and already free bio. Fix it by getting an extra reference to the bio before calling the unmap failure case. Reported-by: Petr Vandrovec Signed-off-by: Jens Axboe

block: make blk_rq_map_user take a NULL user-space buffer

2008-10-09T06:56:11+00:00

This patch changes blk_rq_map_user to accept a NULL user-space buffer with a READ command if rq_map_data is not NULL. Thus a caller can pass page frames to lk_rq_map_user to just set up a request and bios with page frames propely. bio_uncopy_user (called via blk_rq_unmap_user) doesn't copy data to user space with such request. Signed-off-by: FUJITA Tomonori Signed-off-by: Jens Axboe

block: add blk_rq_aligned helper function

2008-10-09T06:56:11+00:00

This adds blk_rq_aligned helper function to see if alignment and padding requirement is satisfied for DMA transfer. This also converts blk_rq_map_kern and __blk_rq_map_user to use the helper function. Signed-off-by: FUJITA Tomonori Cc: Jens Axboe Signed-off-by: Jens Axboe

block: introduce struct rq_map_data to use reserved pages

2008-10-09T06:56:10+00:00

This patch introduces struct rq_map_data to enable bio_copy_use_iov() use reserved pages. Currently, bio_copy_user_iov allocates bounce pages but drivers/scsi/sg.c wants to allocate pages by itself and use them. struct rq_map_data can be used to pass allocated pages to bio_copy_user_iov. The current users of bio_copy_user_iov simply passes NULL (they don't want to use pre-allocated pages). Signed-off-by: FUJITA Tomonori Cc: Jens Axboe Cc: Douglas Gilbert Cc: Mike Christie Cc: James Bottomley Signed-off-by: Jens Axboe

block: add gfp_mask argument to blk_rq_map_user and blk_rq_map_user_iov

2008-10-09T06:56:10+00:00

Currently, blk_rq_map_user and blk_rq_map_user_iov always do GFP_KERNEL allocation. This adds gfp_mask argument to blk_rq_map_user and blk_rq_map_user_iov so sg can use it (sg always does GFP_ATOMIC allocation). Signed-off-by: FUJITA Tomonori Signed-off-by: Douglas Gilbert Cc: Mike Christie Cc: James Bottomley Signed-off-by: Jens Axboe

Add some block/ source files to the kernel-api docbook. Fix kernel-doc notation in them as needed. Fix changed function parameter names. Fix typos/spellos. In comments, change REQ_SPECIAL to REQ_TYPE_SPECIAL and REQ_BLOCK_PC to REQ_TYPE_BLOCK_PC.

2008-10-09T06:56:03+00:00

Signed-off-by: Randy Dunlap Signed-off-by: Jens Axboe

block/blk-map.c: use the new object_is_on_stack() helper

2008-07-26T19:00:02+00:00

Signed-off-by: FUJITA Tomonori Cc: Bartlomiej Zolnierkiewicz Cc: Thomas Bogendoerfer Cc: Tejun Heo Cc: Jens Axboe Cc: James Bottomley Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

block: blk_rq_map_kern uses the bounce buffers for stack buffers

2008-07-04T07:52:13+00:00

blk_rq_map_kern is used for kernel internal I/Os. Some callers use this function with stack buffers but DMA to/from the stack buffers leads to memory corruption on a non-coherent platform. This patch make blk_rq_map_kern uses the bounce buffers if a caller passes a stack buffer (on the all platforms for simplicity). Signed-off-by: FUJITA Tomonori Cc: Bartlomiej Zolnierkiewicz Cc: Thomas Bogendoerfer Cc: Tejun Heo Cc: James Bottomley Signed-off-by: Andrew Morton Signed-off-by: Jens Axboe

block: add bounce support to blk_rq_map_user_iov

2008-07-03T11:21:14+00:00

blk_rq_map_user_iov can't handle the bounce buffer (it means that the bio_map_user_iov path doesn't work with a LLD that needs GFP_DMA). This patch fixes blk_rq_map_user_iov to support the bounce buffer. Signed-off-by: FUJITA Tomonori Cc: Mike Christie Signed-off-by: Jens Axboe