kernel/linux.git/drivers/block/ataflop.c, branch v5.15.208

block: drop unused includes in

2022-03-16T13:23:46+00:00

commit b81e0c2372e65e5627864ba034433b64b2fc73f5 upstream. Drop various include not actually used in genhd.h itself, and move the remaning includes closer together. Signed-off-by: Christoph Hellwig Reviewed-by: Johannes Thumshirn Link: https://lore.kernel.org/r/20210920123328.1399408-15-hch@lst.de Signed-off-by: Jens Axboe Reported-by: Sudip Mukherjee a Reported-by: "H. Nikolaus Schaller" Reported-by: Guenter Roeck Cc: "Maciej W. Rozycki" [ resolves MIPS build failure by luck, root cause needs to be fixed in Linus's tree properly, but this is needed for now to fix the build - gregkh ] Signed-off-by: Greg Kroah-Hartman

ataflop: remove ataflop_probe_lock mutex

2021-11-18T18:17:07+00:00

[ Upstream commit 4ddb85d36613c45bde00d368bf9f357bd0708a0c ] Commit bf9c0538e485b591 ("ataflop: use a separate gendisk for each media format") introduced ataflop_probe_lock mutex, but forgot to unlock the mutex when atari_floppy_init() (i.e. module loading) succeeded. This will result in double lock deadlock if ataflop_probe() is called. Also, unregister_blkdev() must not be called from atari_floppy_init() with ataflop_probe_lock held when atari_floppy_init() failed, for ataflop_probe() waits for ataflop_probe_lock with major_names_lock held (i.e. AB-BA deadlock). __register_blkdev() needs to be called last in order to avoid calling ataflop_probe() when atari_floppy_init() is about to fail, for memory for completing already-started ataflop_probe() safely will be released as soon as atari_floppy_init() released ataflop_probe_lock mutex. As with commit 8b52d8be86d72308 ("loop: reorder loop_exit"), unregister_blkdev() needs to be called first in order to avoid calling ataflop_alloc_disk() from ataflop_probe() after del_gendisk() from atari_floppy_exit(). By relocating __register_blkdev() / unregister_blkdev() as explained above, we can remove ataflop_probe_lock mutex, for probe function and __exit function are serialized by major_names_lock mutex. Signed-off-by: Tetsuo Handa Fixes: bf9c0538e485b591 ("ataflop: use a separate gendisk for each media format") Reviewed-by: Luis Chamberlain Tested-by: Michael Schmitz Link: https://lore.kernel.org/r/20211103230437.1639990-11-mcgrof@kernel.org Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

block/ataflop: provide a helper for cleanup up an atari disk

2021-11-18T18:17:07+00:00

[ Upstream commit deae1138d04758c7f8939fcb8aee330bc37e3015 ] Instead of using two separate code paths for cleaning up an atari disk, use one. We take the more careful approach to check for *all* disk types, as is done on exit. The init path didn't have that check as the alternative disk types are only probed for later, they are not initialized by default. Yes, there is a shared tag for all disks. Signed-off-by: Luis Chamberlain Link: https://lore.kernel.org/r/20210927220302.1073499-14-mcgrof@kernel.org Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

block/ataflop: add registration bool before calling del_gendisk()

2021-11-18T18:17:07+00:00

[ Upstream commit 573effb298011d3fcabc9b12025cf637f8a07911 ] The ataflop assumes del_gendisk() is safe to call, this is only true because add_disk() does not return a failure, but that will change soon. And so, before we get to adding error handling for that case, let's make sure we keep track of which disks actually get registered. Then we use this to only call del_gendisk for them. Signed-off-by: Luis Chamberlain Link: https://lore.kernel.org/r/20210927220302.1073499-13-mcgrof@kernel.org Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

block/ataflop: use the blk_cleanup_disk() helper

2021-11-18T18:17:07+00:00

[ Upstream commit 44a469b6acae6ad05c4acca8429467d1d50a8b8d ] Use the helper to replace two lines with one. Signed-off-by: Luis Chamberlain Link: https://lore.kernel.org/r/20210927220302.1073499-12-mcgrof@kernel.org Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

block: ataflop: more blk-mq refactoring fixes

2021-11-18T18:16:41+00:00

[ Upstream commit d28e4dff085c5a87025c9a0a85fb798bd8e9ca17 ] As it turns out, my earlier patch in commit 86d46fdaa12a (block: ataflop: fix breakage introduced at blk-mq refactoring) was incomplete. This patch fixes any remaining issues found during more testing and code review. Requests exceeding 4 k are handled in 4k segments but __blk_mq_end_request() is never called on these (still sectors outstanding on the request). With redo_fd_request() removed, there is no provision to kick off processing of the next segment, causing requests exceeding 4k to hang. (By setting /sys/block/fd0/queue/max_sectors_k <= 4 as workaround, this behaviour can be avoided). Instead of reintroducing redo_fd_request(), requeue the remainder of the request by calling blk_mq_requeue_request() on incomplete requests (i.e. when blk_update_request() still returns true), and rely on the block layer to queue the residual as new request. Both error handling and formatting needs to release the ST-DMA lock, so call finish_fdc() on these (this was previously handled by redo_fd_request()). finish_fdc() may be called legitimately without the ST-DMA lock held - make sure we only release the lock if we actually held it. In a similar way, early exit due to errors in ataflop_queue_rq() must release the lock. After minor errors, fd_error sets up to recalibrate the drive but never re-runs the current operation (another task handled by redo_fd_request() before). Call do_fd_action() to get the next steps (seek, retry read/write) underway. Signed-off-by: Michael Schmitz Fixes: 6ec3938cff95f (ataflop: convert to blk-mq) CC: linux-block@vger.kernel.org Link: https://lore.kernel.org/r/20211024002013.9332-1-schmitzmic@gmail.com Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

block: ataflop: fix breakage introduced at blk-mq refactoring

2021-11-18T18:16:34+00:00

[ Upstream commit 86d46fdaa12ae5befc16b8d73fc85a3ca0399ea6 ] Refactoring of the Atari floppy driver when converting to blk-mq has broken the state machine in not-so-subtle ways: finish_fdc() must be called when operations on the floppy device have completed. This is crucial in order to relase the ST-DMA lock, which protects against concurrent access to the ST-DMA controller by other drivers (some DMA related, most just related to device register access - broken beyond compare, I know). When rewriting the driver's old do_request() function, the fact that finish_fdc() was called only when all queued requests had completed appears to have been overlooked. Instead, the new request function calls finish_fdc() immediately after the last request has been queued. finish_fdc() executes a dummy seek after most requests, and this overwrites the state machine's interrupt hander that was set up to wait for completion of the read/write request just prior. To make matters worse, finish_fdc() is called before device interrupts are re-enabled, making certain that the read/write interupt is missed. Shifting the finish_fdc() call into the read/write request completion handler ensures the driver waits for the request to actually complete. With a queue depth of 2, we won't see long request sequences, so calling finish_fdc() unconditionally just adds a little overhead for the dummy seeks, and keeps the code simple. While we're at it, kill ataflop_commit_rqs() which does nothing but run finish_fdc() unconditionally, again likely wiping out an in-flight request. Signed-off-by: Michael Schmitz Fixes: 6ec3938cff95 ("ataflop: convert to blk-mq") CC: linux-block@vger.kernel.org CC: Tetsuo Handa Link: https://lore.kernel.org/r/20211019061321.26425-1-schmitzmic@gmail.com Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

ataflop: use blk_mq_alloc_disk and blk_cleanup_disk

2021-06-11T17:54:43+00:00

Use blk_mq_alloc_disk and blk_cleanup_disk to simplify the gendisk and request_queue allocation. Signed-off-by: Christoph Hellwig Reviewed-by: Chaitanya Kulkarni Link: https://lore.kernel.org/r/20210602065345.355274-30-hch@lst.de Signed-off-by: Jens Axboe

ataflop: fix off by one in ataflop_probe()

2021-04-21T15:15:27+00:00

Smatch complains that the "type > NUM_DISK_MINORS" should be >= instead of >. We also need to subtract one from "type" at the start. Fixes: bf9c0538e485 ("ataflop: use a separate gendisk for each media format") Reported-by: kernel test robot Signed-off-by: Dan Carpenter Reviewed-by: Christoph Hellwig Signed-off-by: Jens Axboe

ataflop: potential out of bounds in do_format()

2021-04-21T15:15:25+00:00

The function uses "type" as an array index: q = unit[drive].disk[type]->queue; Unfortunately the bounds check on "type" isn't done until later in the function. Fix this by moving the bounds check to the start. Fixes: bf9c0538e485 ("ataflop: use a separate gendisk for each media format") Reported-by: kernel test robot Signed-off-by: Dan Carpenter Reviewed-by: Christoph Hellwig Signed-off-by: Jens Axboe