kernel/linux.git/drivers/block/floppy.c, branch v7.0-rc7

array_size.h: add ARRAY_END()

2026-01-21T03:44:19+00:00

Patch series "Add ARRAY_END(), and use it to fix off-by-one bugs", v6. Add ARRAY_END(), and use it to fix off-by-one bugs ARRAY_END() is a macro to calculate a pointer to one past the last element of an array argument. This is a very common pointer, which is used to iterate over all elements of an array: for (T *p = a; p < ARRAY_END(a); p++) ... Of course, this pointer should never be dereferenced. A pointer one past the last element of an array should not be dereferenced; it's perfectly fine to hold such a pointer --and a good thing to do--, but the only thing it should be used for is comparing it with other pointers derived from the same array. Due to how special these pointers are, it would be good to use consistent naming. It's common to name such a pointer 'end' --in fact, we have many such cases in the kernel--. C++ even standardized this name with std::end(). Let's try naming such pointers 'end', and try also avoid using 'end' for pointers that are not the result of ARRAY_END(). It has been incorrectly suggested that these pointers are dangerous, and that they should never be used, suggesting to use something like #define ARRAY_LAST(a) ((a) + ARRAY_SIZE(a) - 1) for (T *p = a; p <= ARRAY_LAST(a); p++) ... This is bogus, as it doesn't scale down to arrays of 0 elements. In the case of an array of 0 elements, ARRAY_LAST() would underflow the pointer, which not only it can't be dereferenced, it can't even be held (it produces Undefined Behavior). That would be a footgun. Such arrays don't exist per the ISO C standard; however, GCC supports them as an extension (with partial support, though; GCC has a few bugs which need to be fixed). This patch set fixes a few places where it was intended to use the array end (that is, one past the last element), but accidentally a pointer to the last element was used instead, thus wasting one byte. It also replaces other places where the array end was correctly calculated with ARRAY_SIZE(), by using the simpler ARRAY_END(). Also, there was one drivers/ file that already defined this macro. We remove that definition, to not conflict with this one. This patch (of 4): ARRAY_END() returns a pointer one past the end of the last element in the array argument. This pointer is useful for iterating over the elements of an array: for (T *p = a, p < ARRAY_END(a); p++) ... Link: https://lkml.kernel.org/r/cover.1765449750.git.alx@kernel.org Link: https://lkml.kernel.org/r/5973cfb674192bc8e533485dbfb54e3062896be1.1765449750.git.alx@kernel.org Signed-off-by: Alejandro Colomar Cc: Kees Cook Cc: Christopher Bazley Cc: Rasmus Villemoes Cc: Marco Elver Cc: Michal Hocko Cc: Linus Torvalds Cc: Al Viro Cc: Alexander Potapenko Cc: Dmitriy Vyukov Cc: Jann Horn Cc: Maciej W. Rozycki Signed-off-by: Andrew Morton

floppy: fix for PAGE_SIZE != 4KB

2025-11-17T15:22:00+00:00

For years I wondered why the floppy driver does not just work on sparc64, e.g: root@SUNW_375_0066:# disktype /dev/fd0 disktype: Can't open /dev/fd0: No such device or address [ 525.341906] disktype: attempt to access beyond end of device fd0: rw=0, sector=0, nr_sectors = 16 limit=8 [ 525.341991] floppy: error 10 while reading block 0 Turns out floppy.c __floppy_read_block_0 tries to read one page for the first test read to determine the disk size and thus fails if that is greater than 4k. Adjust minimum MAX_DISK_SIZE to PAGE_SIZE to fix floppy on sparc64 and likely all other PAGE_SIZE != 4KB configs. Cc: stable@vger.kernel.org Signed-off-by: René Rebe Signed-off-by: Jens Axboe

block: floppy: Replace kmalloc() + copy_from_user() with memdup_user()

2025-09-09T15:10:58+00:00

Replace kmalloc() followed by copy_from_user() with memdup_user() to improve and simplify raw_cmd_copyin(). No functional changes intended. Signed-off-by: Thorsten Blum Signed-off-by: Jens Axboe

Merge tag 'pull-getgeo' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs into for-6.18/block

2025-09-03T21:15:43+00:00

Pull struct block_device getgeo changes from Al. "switching ->getgeo() from struct block_device to struct gendisk Signed-off-by: Al Viro " * tag 'pull-getgeo' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: block: switch ->getgeo() to struct gendisk scsi: switch ->bios_param() to passing gendisk scsi: switch scsi_bios_ptable() and scsi_partsize() to gendisk

floppy: Sort headers alphabetically

2025-08-25T20:46:42+00:00

Sorting headers alphabetically helps locating duplicates, and makes it easier to figure out where to insert new headers. Signed-off-by: Andy Shevchenko Link: https://lore.kernel.org/r/20250825163545.39303-4-andriy.shevchenko@linux.intel.com Signed-off-by: Jens Axboe

floppy: Replace custom SZ_64K constant

2025-08-25T20:46:42+00:00

There are only two headers using the K_64 custom constant. Moreover, its usage tangles a code because the constant is defined in the C file, while users are in the headers. Replace it with well defined SZ_64K from sizes.h. Acked-by: Helge Deller Signed-off-by: Andy Shevchenko Link: https://lore.kernel.org/r/20250825163545.39303-3-andriy.shevchenko@linux.intel.com Signed-off-by: Jens Axboe

block: switch ->getgeo() to struct gendisk

2025-08-13T06:59:29+00:00

Instances are happier that way and it makes more sense anyway - the only part of the result that is related to partition we are given is the start sector, and that has been filled in by the caller. Everything else is a function of the disk. Only one instance (DASD) is ever looking at anything other than bdev->bd_disk and that one is trivial to adjust. Reviewed-by: Martin K. Petersen Reviewed-by: Christoph Hellwig Acked-by: Jens Axboe Signed-off-by: Al Viro

block: floppy: Fix uninitialized use of outparam

2025-07-13T18:08:31+00:00

Fix Smatch-detected error: drivers/block/floppy.c:3569 fd_locked_ioctl() error: uninitialized symbol 'outparam'. Smatch may incorrectly warn about uninitialized use of 'outparam' in fd_locked_ioctl(), even though all _IOC_READ commands guarantee its initialization. Initialize outparam to NULL to make this explicit and suppress the false positive. Signed-off-by: Purva Yeshi Reviewed-by: Denis Efremov Link: https://lore.kernel.org/r/20250713070020.14530-1-purvayeshi550@gmail.com Signed-off-by: Jens Axboe

treewide: Switch/rename to timer_delete[_sync]()

2025-04-05T08:30:12+00:00

timer_delete[_sync]() replaces del_timer[_sync](). Convert the whole tree over and remove the historical wrapper inlines. Conversion was done with coccinelle plus manual fixups where necessary. Signed-off-by: Thomas Gleixner Signed-off-by: Ingo Molnar

block: remove BLK_MQ_F_SHOULD_MERGE

2024-12-23T15:17:23+00:00

BLK_MQ_F_SHOULD_MERGE is set for all tag_sets except those that purely process passthrough commands (bsg-lib, ufs tmf, various nvme admin queues) and thus don't even check the flag. Remove it to simplify the driver interface. Signed-off-by: Christoph Hellwig Link: https://lore.kernel.org/r/20241219060214.1928848-1-hch@lst.de Signed-off-by: Jens Axboe