kernel/linux.git/drivers/md/dm-table.c, branch v5.7.4

block: don't handle bio based drivers in blk_revalidate_disk_zones

2019-12-03T15:51:25+00:00

bio based drivers only need to update q->nr_zones. Do that manually instead of overloading blk_revalidate_disk_zones to keep that function simpler for the next round of changes that will rely even more on the request based functionality. Reviewed-by: Javier González Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe

dm table: do not allow request-based DM to stack on partitions

2019-11-05T16:22:52+00:00

Partitioned request-based devices cannot be used as underlying devices for request-based DM because no partition offsets are added to each incoming request. As such, until now, stacking on partitioned devices would _always_ result in data corruption (e.g. wiping the partition table, writing to other partitions, etc). Fix this by disallowing request-based stacking on partitions. While at it, since all .request_fn support has been removed from block core, remove legacy dm-table code that differentiated between blk-mq and .request_fn request-based. Signed-off-by: Mike Snitzer

dm: make dm_table_find_target return NULL

2019-08-23T14:13:12+00:00

Currently, if we pass too high sector number to dm_table_find_target, it returns zeroed dm_target structure and callers test if the structure is zeroed with the macro dm_target_is_valid. However, returning NULL is common practice to indicate errors. This patch refactors the dm code, so that dm_table_find_target returns NULL and its callers test the returned value for NULL. The macro dm_target_is_valid is deleted. In alloc_targets, we no longer allocate an extra zeroed target. Signed-off-by: Mikulas Patocka Signed-off-by: Mike Snitzer

dm table: fix invalid memory accesses with too high sector number

2019-08-23T14:11:42+00:00

If the sector number is too high, dm_table_find_target() should return a pointer to a zeroed dm_target structure (the caller should test it with dm_target_is_valid). However, for some table sizes, the code in dm_table_find_target() that performs btree lookup will access out of bound memory structures. Fix this bug by testing the sector number at the beginning of dm_table_find_target(). Also, add an "inline" keyword to the function dm_table_get_size() because this is a hot path. Fixes: 512875bd9661 ("dm: table detect io beyond device") Cc: stable@vger.kernel.org Reported-by: Zhang Tao Signed-off-by: Mikulas Patocka Signed-off-by: Mike Snitzer

dm table: fix various whitespace issues with recent DAX code

2019-07-30T22:59:24+00:00

Also, rename device_synchronous to device_dax_synchronous. Signed-off-by: Mike Snitzer

dm table: fix dax_dev NULL dereference in device_synchronous()

2019-07-30T22:58:54+00:00

If a device doesn't support DAX its 'dax_dev' is NULL. Fix device_synchronous() to first check if dax_dev is NULL before dereferencing it. Fixes: 2e9ee0955d3c ("dm: enable synchronous dax") Reported-by: jencce.kernel@gmail.com Signed-off-by: Pankaj Gupta Acked-by: Dan Williams Signed-off-by: Mike Snitzer

Merge tag 'libnvdimm-for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

2019-07-18T17:52:08+00:00

Pull libnvdimm updates from Dan Williams: "Primarily just the virtio_pmem driver: - virtio_pmem The new virtio_pmem facility introduces a paravirtualized persistent memory device that allows a guest VM to use DAX mechanisms to access a host-file with host-page-cache. It arranges for MAP_SYNC to be disabled and instead triggers a host fsync() when a 'write-cache flush' command is sent to the virtual disk device. - Miscellaneous small fixups" * tag 'libnvdimm-for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: virtio_pmem: fix sparse warning xfs: disable map_sync for async flush ext4: disable map_sync for async flush dax: check synchronous mapping is supported dm: enable synchronous dax libnvdimm: add dax_dev sync flag virtio-pmem: Add virtio pmem driver libnvdimm: nd_region flush callback support libnvdimm, namespace: Drop uuid_t implementation detail

dm: enable synchronous dax

2019-07-05T22:19:10+00:00

This patch sets dax device 'DAXDEV_SYNC' flag if all the target devices of device mapper support synchrononous DAX. If device mapper consists of both synchronous and asynchronous dax devices, we don't set 'DAXDEV_SYNC' flag. 'dm_table_supports_dax' is refactored to pass 'iterate_devices_fn' as argument so that the callers can pass the appropriate functions. Suggested-by: Mike Snitzer Signed-off-by: Pankaj Gupta Reviewed-by: Mike Snitzer Signed-off-by: Dan Williams

dm table: don't copy from a NULL pointer in realloc_argv()

2019-06-25T18:09:13+00:00

For the first call to realloc_argv() in dm_split_args(), old_argv is NULL and size is zero. Then memcpy is called, with the NULL old_argv as the source argument and a zero size argument. AFAIK, this is undefined behavior and generates the following warning when compiled with UBSAN on ppc64le: In file included from ./arch/powerpc/include/asm/paca.h:19, from ./arch/powerpc/include/asm/current.h:16, from ./include/linux/sched.h:12, from ./include/linux/kthread.h:6, from drivers/md/dm-core.h:12, from drivers/md/dm-table.c:8: In function 'memcpy', inlined from 'realloc_argv' at drivers/md/dm-table.c:565:3, inlined from 'dm_split_args' at drivers/md/dm-table.c:588:9: ./include/linux/string.h:345:9: error: argument 2 null where non-null expected [-Werror=nonnull] return __builtin_memcpy(p, q, size); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/md/dm-table.c: In function 'dm_split_args': ./include/linux/string.h:345:9: note: in a call to built-in function '__builtin_memcpy' Signed-off-by: Jerome Marchand Signed-off-by: Mike Snitzer

dax: Arrange for dax_supported check to span multiple devices

2019-05-20T22:02:08+00:00

Pankaj reports that starting with commit ad428cdb525a "dax: Check the end of the block-device capacity with dax_direct_access()" device-mapper no longer allows dax operation. This results from the stricter checks in __bdev_dax_supported() that validate that the start and end of a block-device map to the same 'pagemap' instance. Teach the dax-core and device-mapper to validate the 'pagemap' on a per-target basis. This is accomplished by refactoring the bdev_dax_supported() internals into generic_fsdax_supported() which takes a sector range to validate. Consequently generic_fsdax_supported() is suitable to be used in a device-mapper ->iterate_devices() callback. A new ->dax_supported() operation is added to allow composite devices to split and route upper-level bdev_dax_supported() requests. Fixes: ad428cdb525a ("dax: Check the end of the block-device...") Cc: Cc: Ira Weiny Cc: Dave Jiang Cc: Keith Busch Cc: Matthew Wilcox Cc: Vishal Verma Cc: Heiko Carstens Cc: Martin Schwidefsky Reviewed-by: Jan Kara Reported-by: Pankaj Gupta Reviewed-by: Pankaj Gupta Tested-by: Pankaj Gupta Tested-by: Vaibhav Jain Reviewed-by: Mike Snitzer Signed-off-by: Dan Williams