linux/fs/f2fs
Linus Torvalds c03098d4b9 gfs2: Fix mmap + page fault deadlocks
Functions gfs2_file_read_iter and gfs2_file_write_iter are both
 accessing the user buffer to write to or read from while holding the
 inode glock.  In the most basic scenario, that buffer will not be
 resident and it will be mapped to the same file.  Accessing the buffer
 will trigger a page fault, and gfs2 will deadlock trying to take the
 same inode glock again while trying to handle that fault.
 
 Fix that and similar, more complex scenarios by disabling page faults
 while accessing user buffers.  To make this work, introduce a small
 amount of new infrastructure and fix some bugs that didn't trigger so
 far, with page faults enabled.
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Merge tag 'gfs2-v5.15-rc5-mmap-fault' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2

Pull gfs2 mmap + page fault deadlocks fixes from Andreas Gruenbacher:
 "Functions gfs2_file_read_iter and gfs2_file_write_iter are both
  accessing the user buffer to write to or read from while holding the
  inode glock.

  In the most basic deadlock scenario, that buffer will not be resident
  and it will be mapped to the same file. Accessing the buffer will
  trigger a page fault, and gfs2 will deadlock trying to take the same
  inode glock again while trying to handle that fault.

  Fix that and similar, more complex scenarios by disabling page faults
  while accessing user buffers. To make this work, introduce a small
  amount of new infrastructure and fix some bugs that didn't trigger so
  far, with page faults enabled"

* tag 'gfs2-v5.15-rc5-mmap-fault' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  gfs2: Fix mmap + page fault deadlocks for direct I/O
  iov_iter: Introduce nofault flag to disable page faults
  gup: Introduce FOLL_NOFAULT flag to disable page faults
  iomap: Add done_before argument to iomap_dio_rw
  iomap: Support partial direct I/O on user copy failures
  iomap: Fix iomap_dio_rw return value for user copies
  gfs2: Fix mmap + page fault deadlocks for buffered I/O
  gfs2: Eliminate ip->i_gh
  gfs2: Move the inode glock locking to gfs2_file_buffered_write
  gfs2: Introduce flag for glock holder auto-demotion
  gfs2: Clean up function may_grant
  gfs2: Add wrapper for iomap_file_buffered_write
  iov_iter: Introduce fault_in_iov_iter_writeable
  iov_iter: Turn iov_iter_fault_in_readable into fault_in_iov_iter_readable
  gup: Turn fault_in_pages_{readable,writeable} into fault_in_{readable,writeable}
  powerpc/kvm: Fix kvm_use_magic_page
  iov_iter: Fix iov_iter_get_pages{,_alloc} page fault return value
2021-11-02 12:25:03 -07:00
..
acl.c vfs: add rcu argument to ->get_acl() callback 2021-08-18 22:08:24 +02:00
acl.h vfs: add rcu argument to ->get_acl() callback 2021-08-18 22:08:24 +02:00
checkpoint.c f2fs: rebuild nat_bits during umount 2021-08-23 10:25:52 -07:00
compress.c mm: don't include <linux/blk-cgroup.h> in <linux/backing-dev.h> 2021-10-18 06:17:01 -06:00
data.c f2fs-for-5.15-rc1 2021-09-04 10:48:47 -07:00
debug.c f2fs: convert S_IRUGO to 0444 2021-08-17 11:59:05 -07:00
dir.c f2fs: support fault injection for f2fs_kmem_cache_alloc() 2021-08-17 11:59:05 -07:00
extent_cache.c f2fs: support fault injection for f2fs_kmem_cache_alloc() 2021-08-17 11:59:05 -07:00
f2fs.h f2fs-for-5.15-rc1 2021-09-04 10:48:47 -07:00
file.c iov_iter: Turn iov_iter_fault_in_readable into fault_in_iov_iter_readable 2021-10-18 16:35:06 +02:00
gc.c f2fs: fix to account missing .skipped_gc_rwsem 2021-08-30 10:12:47 -07:00
gc.h f2fs: introduce gc_merge mount option 2021-03-30 18:48:56 -07:00
hash.c f2fs: Handle casefolding with Encryption 2020-12-02 22:00:21 -08:00
inline.c f2fs: restructure f2fs page.private layout 2021-05-14 11:22:08 -07:00
inode.c f2fs: compress: add compress_inode to cache compressed blocks 2021-06-23 01:09:35 -07:00
iostat.c f2fs: introduce periodic iostat io latency traces 2021-08-23 10:25:51 -07:00
iostat.h f2fs: introduce periodic iostat io latency traces 2021-08-23 10:25:51 -07:00
Kconfig f2fs: separate out iostat feature 2021-08-23 10:25:51 -07:00
Makefile f2fs: separate out iostat feature 2021-08-23 10:25:51 -07:00
namei.c f2fs: report correct st_size for encrypted symlinks 2021-07-25 20:01:06 -07:00
node.c f2fs: rebuild nat_bits during umount 2021-08-23 10:25:52 -07:00
node.h f2fs: swap: support migrating swapfile in aligned write mode 2021-06-23 01:09:35 -07:00
recovery.c f2fs: support fault injection for f2fs_kmem_cache_alloc() 2021-08-17 11:59:05 -07:00
segment.c f2fs: Don't create discard thread when device doesn't support realtime discard 2021-08-30 10:12:46 -07:00
segment.h f2fs: correct comment in segment.h 2021-08-13 11:57:08 -07:00
shrinker.c f2fs: avoid race condition for shrinker count 2020-12-03 00:59:26 -08:00
super.c fscrypt: remove fscrypt_operations::max_namelen 2021-09-20 19:32:33 -07:00
sysfs.c f2fs-for-5.15-rc1 2021-09-04 10:48:47 -07:00
verity.c f2fs-for-5.13-rc1 2021-05-04 18:03:38 -07:00
xattr.c f2fs: support fault injection for f2fs_kmem_cache_alloc() 2021-08-17 11:59:05 -07:00
xattr.h f2fs: code cleanup by removing ifdef macro surrounding 2020-05-26 18:56:10 -07:00