kernel/linux.git/drivers/md/dm-table.c, branch linux-4.20.y

dm: do not allow readahead to limit IO size

2019-01-13T08:24:05+00:00

commit c6d6e9b0f6b4201c77f2cea3964dd122697e3543 upstream. Update DM to set the bdi's io_pages. This fixes reads to be capped at the device's max request size (even if user's read IO exceeds the established readahead setting). Fixes: 9491ae4a ("mm: don't cap request size based on read-ahead setting") Cc: stable@vger.kernel.org Reviewed-by: Jens Axboe Signed-off-by: Jaegeuk Kim Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman

Merge tag 'for-4.20/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

2018-10-26T19:57:38+00:00

Pull device mapper updates from Mike Snitzer: - The biggest change this cycle is to remove support for the legacy IO path (.request_fn) from request-based DM. Jens has already started preparing for complete removal of the legacy IO path in 4.21 but this earlier removal of support from DM has been coordinated with Jens (as evidenced by the commit being attributed to him). Making request-based DM exclussively blk-mq only cleans up that portion of DM core quite nicely. - Convert the thinp and zoned targets over to using refcount_t where applicable. - A couple fixes to the DM zoned target for refcounting and other races buried in the implementation of metadata block creation and use. - Small cleanups to remove redundant unlikely() around a couple WARN_ON_ONCE(). - Simplify how dm-ioctl copies from userspace, eliminating some potential for a malicious user trying to change the executed ioctl after its processing has begun. - Tweaked DM crypt target to use the DM device name when naming the various workqueues created for a particular DM crypt device (makes the N workqueues for a DM crypt device more easily understood and enhances user's accounting capabilities at a glance via "ps") - Small fixup to remove dead branch in DM writecache's memory_entry(). * tag 'for-4.20/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: dm writecache: remove disabled code in memory_entry() dm zoned: fix various dmz_get_mblock() issues dm zoned: fix metadata block ref counting dm raid: avoid bitmap with raid4/5/6 journal device dm crypt: make workqueue names device-specific dm: add dm_table_device_name() dm ioctl: harden copy_params()'s copy_from_user() from malicious users dm: remove unnecessary unlikely() around WARN_ON_ONCE() dm zoned: target: use refcount_t for dm zoned reference counters dm thin: use refcount_t for thin_c reference counting dm table: require that request-based DM be layered on blk-mq devices dm: rename DM_TYPE_MQ_REQUEST_BASED to DM_TYPE_REQUEST_BASED dm: remove legacy request-based IO path

block: Introduce blk_revalidate_disk_zones()

2018-10-25T17:17:40+00:00

Drivers exposing zoned block devices have to initialize and maintain correctness (i.e. revalidate) of the device zone bitmaps attached to the device request queue (seq_zones_bitmap and seq_zones_wlock). To simplify coding this, introduce a generic helper function blk_revalidate_disk_zones() suitable for most (and likely all) cases. This new function always update the seq_zones_bitmap and seq_zones_wlock bitmaps as well as the queue nr_zones field when called for a disk using a request based queue. For a disk using a BIO based queue, only the number of zones is updated since these queues do not have schedulers and so do not need the zone bitmaps. With this change, the zone bitmap initialization code in sd_zbc.c can be replaced with a call to this function in sd_zbc_read_zones(), which is called from the disk revalidate block operation method. A call to blk_revalidate_disk_zones() is also added to the null_blk driver for devices created with the zoned mode enabled. Finally, to ensure that zoned devices created with dm-linear or dm-flakey expose the correct number of zones through sysfs, a call to blk_revalidate_disk_zones() is added to dm_table_set_restrictions(). The zone bitmaps allocated and initialized with blk_revalidate_disk_zones() are freed automatically from __blk_release_queue() using the block internal function blk_queue_free_zone_bitmaps(). Reviewed-by: Hannes Reinecke Reviewed-by: Christoph Hellwig Reviewed-by: Martin K. Petersen Reviewed-by: Mike Snitzer Signed-off-by: Damien Le Moal Signed-off-by: Jens Axboe

dm: add dm_table_device_name()

2018-10-18T16:10:02+00:00

Add a shortcut for dm_device_name(dm_table_get_md(t)). Signed-off-by: Michał Mirosław Signed-off-by: Mike Snitzer

dm table: require that request-based DM be layered on blk-mq devices

2018-10-11T21:51:13+00:00

Now that request-based DM (multipath) is blk-mq only: this restriction is required while the legacy request-based IO path still exists. Signed-off-by: Mike Snitzer

dm: rename DM_TYPE_MQ_REQUEST_BASED to DM_TYPE_REQUEST_BASED

2018-10-11T15:36:09+00:00

Now that request-based DM is only using blk-mq, there is no need to differentiate between legacy "rq" and new "mq". We're back to a single request-based DM -- and there was much rejoicing! Signed-off-by: Mike Snitzer

dm: remove legacy request-based IO path

2018-10-11T15:36:09+00:00

dm supports both, and since we're killing off the legacy path in general, get rid of it in dm. Signed-off-by: Jens Axboe Signed-off-by: Mike Snitzer

dm: prevent DAX mounts if not supported

2018-06-28T20:06:14+00:00

Currently device_supports_dax() just checks to see if the QUEUE_FLAG_DAX flag is set on the device's request queue to decide whether or not the device supports filesystem DAX. Really we should be using bdev_dax_supported() like filesystems do at mount time. This performs other tests like checking to make sure the dax_direct_access() path works. We also explicitly clear QUEUE_FLAG_DAX on the DM device's request queue if any of the underlying devices do not support DAX. This makes the handling of QUEUE_FLAG_DAX consistent with the setting/clearing of most other flags in dm_table_set_restrictions(). Now that bdev_dax_supported() explicitly checks for QUEUE_FLAG_DAX, this will ensure that filesystems built upon DM devices will only be able to mount with DAX if all underlying devices also support DAX. Signed-off-by: Ross Zwisler Fixes: commit 545ed20e6df6 ("dm: add infrastructure for DAX support") Cc: stable@vger.kernel.org Acked-by: Dan Williams Reviewed-by: Toshi Kani Signed-off-by: Mike Snitzer

treewide: kmalloc() -> kmalloc_array()

2018-06-12T23:19:22+00:00

The kmalloc() function has a 2-factor argument form, kmalloc_array(). This patch replaces cases of: kmalloc(a * b, gfp) with: kmalloc_array(a * b, gfp) as well as handling cases of: kmalloc(a * b * c, gfp) with: kmalloc(array3_size(a, b, c), gfp) as it's slightly less ugly than: kmalloc_array(array_size(a, b), c, gfp) This does, however, attempt to ignore constant size factors like: kmalloc(4 * 1024, gfp) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The tools/ directory was manually excluded, since it has its own implementation of kmalloc(). The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( kmalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | kmalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( kmalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(char) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(u8) * COUNT + COUNT , ...) | kmalloc( - sizeof(__u8) * COUNT + COUNT , ...) | kmalloc( - sizeof(char) * COUNT + COUNT , ...) | kmalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - kmalloc + kmalloc_array ( - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ - kmalloc + kmalloc_array ( - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( kmalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( kmalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kmalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kmalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( kmalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( kmalloc(C1 * C2 * C3, ...) | kmalloc( - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | kmalloc( - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | kmalloc( - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | kmalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( kmalloc(sizeof(THING) * C2, ...) | kmalloc(sizeof(TYPE) * C2, ...) | kmalloc(C1 * C2 * C3, ...) | kmalloc(C1 * C2, ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - (E1) * E2 + E1, E2 , ...) | - kmalloc + kmalloc_array ( - (E1) * (E2) + E1, E2 , ...) | - kmalloc + kmalloc_array ( - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook

overflow.h: Add allocation size calculation helpers

2018-06-05T19:16:51+00:00

In preparation for replacing unchecked overflows for memory allocations, this creates helpers for the 3 most common calculations: array_size(a, b): 2-dimensional array array3_size(a, b, c): 3-dimensional array struct_size(ptr, member, n): struct followed by n-many trailing members Each of these return SIZE_MAX on overflow instead of wrapping around. (Additionally renames a variable named "array_size" to avoid future collision.) Co-developed-by: Matthew Wilcox Signed-off-by: Kees Cook