linux/fs/btrfs
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
..
tests btrfs: subpage: avoid potential deadlock with compression and delalloc 2021-10-26 19:08:05 +02:00
acl.c overlayfs update for 5.15 2021-09-02 09:21:27 -07:00
async-thread.c
async-thread.h
backref.c btrfs: remove ignore_offset argument from btrfs_find_all_roots() 2021-08-23 13:19:01 +02:00
backref.h btrfs: remove ignore_offset argument from btrfs_find_all_roots() 2021-08-23 13:19:01 +02:00
block-group.c btrfs: update comments for chunk allocation -ENOSPC cases 2021-10-26 19:08:07 +02:00
block-group.h btrfs: fix deadlock between chunk allocation and chunk btree modifications 2021-10-26 19:08:07 +02:00
block-rsv.c btrfs: introduce mount option rescue=ignorebadroots 2020-12-08 15:53:41 +01:00
block-rsv.h
btrfs_inode.h btrfs: rename btrfs_dio_private::logical_offset to file_offset 2021-10-26 19:08:06 +02:00
check-integrity.c btrfs: check-integrity: stop storing the block device name in btrfsic_dev_state 2021-10-26 19:08:07 +02:00
check-integrity.h
compression.c for-5.16-tag 2021-11-01 12:48:25 -07:00
compression.h btrfs: determine stripe boundary at bio allocation time in btrfs_submit_compressed_write 2021-10-26 19:08:04 +02:00
ctree.c for-5.16-tag 2021-11-01 12:48:25 -07:00
ctree.h btrfs: remove root argument from btrfs_unlink_inode() 2021-10-29 12:39:13 +02:00
delalloc-space.c btrfs: fix typos in comments 2021-06-22 14:11:57 +02:00
delalloc-space.h btrfs: make btrfs_delalloc_reserve_space take btrfs_inode 2020-07-27 12:55:36 +02:00
delayed-inode.c btrfs: loop only once over data sizes array when inserting an item batch 2021-10-26 19:08:03 +02:00
delayed-inode.h btrfs: make btrfs_delayed_update_inode take btrfs_inode 2020-12-08 15:54:10 +01:00
delayed-ref.c btrfs: pull up qgroup checks from delayed-ref core to init time 2021-10-26 19:08:06 +02:00
delayed-ref.h btrfs: make btrfs_ref::real_root optional 2021-10-26 19:08:06 +02:00
dev-replace.c for-5.16-tag 2021-11-01 12:48:25 -07:00
dev-replace.h btrfs: zoned: mark block groups to copy for device-replace 2021-02-09 02:46:07 +01:00
dir-item.c btrfs: unify lookup return value when dir entry is missing 2021-10-07 22:06:32 +02:00
discard.c btrfs: fix typos in comments 2021-06-22 14:11:57 +02:00
discard.h btrfs: cleanup btrfs_discard_update_discardable usage 2020-12-08 15:54:02 +01:00
disk-io.c for-5.16-tag 2021-11-01 12:48:25 -07:00
disk-io.h btrfs: make btrfs_super_block size match BTRFS_SUPER_INFO_SIZE 2021-10-26 19:08:07 +02:00
export.c btrfs: locking: rip out path->leave_spinning 2020-12-08 15:54:02 +01:00
export.h
extent_io.c btrfs: remove btrfs_bio::logical member 2021-10-26 19:08:06 +02:00
extent_io.h btrfs: cleanup for extent_write_locked_range() 2021-10-26 19:08:04 +02:00
extent_map.c btrfs: rename btrfs_bio to btrfs_io_context 2021-10-26 19:08:02 +02:00
extent_map.h
extent-io-tree.h btrfs: use fixed width int type for extent_state::state 2020-12-08 15:54:13 +01:00
extent-tree.c btrfs: reduce btrfs_update_block_group alloc argument to bool 2021-10-26 19:08:06 +02:00
file-item.c btrfs: use bvec_kmap_local in btrfs_csum_one_bio 2021-10-26 19:08:06 +02:00
file.c gfs2: Fix mmap + page fault deadlocks 2021-11-02 12:25:03 -07:00
free-space-cache.c btrfs: subpage: add bitmap for PageChecked flag 2021-10-26 19:08:03 +02:00
free-space-cache.h btrfs: zoned: track unusable bytes for zones 2021-02-09 02:46:03 +01:00
free-space-tree.c btrfs: fix possible free space tree corruption with online conversion 2021-01-25 18:44:37 +01:00
free-space-tree.h
inode-item.c btrfs: locking: rip out path->leave_spinning 2020-12-08 15:54:02 +01:00
inode.c for-5.16-tag 2021-11-01 12:48:25 -07:00
ioctl.c gfs2: Fix mmap + page fault deadlocks 2021-11-02 12:25:03 -07:00
Kconfig btrfs: disable build on platforms having page size 256K 2021-06-22 14:11:57 +02:00
locking.c btrfs: fix typos in comments 2021-06-22 14:11:57 +02:00
locking.h btrfs: assert that extent buffers are write locked instead of only locked 2021-10-26 19:08:02 +02:00
lzo.c for-5.16-tag 2021-11-01 12:48:25 -07:00
Makefile btrfs: initial fsverity support 2021-08-23 13:19:09 +02:00
misc.h btrfs: use correct header for div_u64 in misc.h 2021-09-07 14:29:50 +02:00
ordered-data.c btrfs: zoned: fix double counting of split ordered extent 2021-09-07 14:30:41 +02:00
ordered-data.h btrfs: remove uptodate parameter from btrfs_dec_test_first_ordered_pending 2021-08-23 13:19:02 +02:00
orphan.c
print-tree.c btrfs: print the actual offset in btrfs_root_name 2021-01-07 17:25:05 +01:00
print-tree.h btrfs: print the actual offset in btrfs_root_name 2021-01-07 17:25:05 +01:00
props.c btrfs: props: change how empty value is interpreted 2021-06-22 14:11:58 +02:00
props.h
qgroup.c btrfs: remove ignore_offset argument from btrfs_find_all_roots() 2021-08-23 13:19:01 +02:00
qgroup.h btrfs: fix lock inversion problem when doing qgroup extent tracing 2021-07-22 15:50:07 +02:00
raid56.c btrfs: remove btrfs_raid_bio::fs_info member 2021-10-26 19:08:03 +02:00
raid56.h btrfs: remove btrfs_raid_bio::fs_info member 2021-10-26 19:08:03 +02:00
rcu-string.h
reada.c btrfs: rename btrfs_bio to btrfs_io_context 2021-10-26 19:08:02 +02:00
ref-verify.c btrfs: rename root fields in delayed refs structs 2021-10-26 19:08:06 +02:00
ref-verify.h
reflink.c btrfs: subpage: add bitmap for PageChecked flag 2021-10-26 19:08:03 +02:00
reflink.h
relocation.c btrfs: fix deadlock between chunk allocation and chunk btree modifications 2021-10-26 19:08:07 +02:00
root-tree.c btrfs: Use memset_startat() to clear end of struct 2021-10-18 12:28:52 -07:00
scrub.c btrfs: handle device lookup with btrfs_dev_lookup_args 2021-10-26 19:08:07 +02:00
send.c btrfs: send: prepare for v2 protocol 2021-10-29 12:38:43 +02:00
send.h btrfs: send: prepare for v2 protocol 2021-10-29 12:38:43 +02:00
space-info.c btrfs: do not infinite loop in data reclaim if we aborted 2021-10-26 19:08:05 +02:00
space-info.h btrfs: rip out btrfs_space_info::total_bytes_pinned 2021-06-22 14:55:25 +02:00
struct-funcs.c btrfs: add special case to setget helpers for 64k pages 2021-08-23 13:18:58 +02:00
subpage.c btrfs: handle page locking in btrfs_page_end_writer_lock with no writers 2021-10-26 19:08:05 +02:00
subpage.h btrfs: rework page locking in __extent_writepage() 2021-10-26 19:08:05 +02:00
super.c btrfs: add a BTRFS_FS_ERROR helper 2021-10-26 19:08:05 +02:00
sysfs.c btrfs: sysfs: convert scnprintf and snprintf to sysfs_emit 2021-10-26 19:08:07 +02:00
sysfs.h btrfs: split and refactor btrfs_sysfs_remove_devices_dir 2020-10-07 12:12:21 +02:00
transaction.c btrfs: add a BTRFS_FS_ERROR helper 2021-10-26 19:08:05 +02:00
transaction.h btrfs: rework chunk allocation to avoid exhaustion of the system chunk array 2021-07-07 17:42:41 +02:00
tree-checker.c btrfs: add ro compat flags to inodes 2021-08-23 13:19:09 +02:00
tree-checker.h
tree-defrag.c btrfs: locking: remove all the blocking helpers 2020-12-08 15:54:01 +01:00
tree-log.c btrfs: remove root argument from check_item_in_log() 2021-10-29 12:39:13 +02:00
tree-log.h btrfs: change error handling for btrfs_delete_*_in_log 2021-10-26 19:08:05 +02:00
tree-mod-log.c btrfs: fix race when picking most recent mod log operation for an old root 2021-04-20 19:27:17 +02:00
tree-mod-log.h btrfs: add and use helper to get lowest sequence number for the tree mod log 2021-04-19 17:25:17 +02:00
ulist.c
ulist.h
uuid-tree.c btrfs: remove unnecessary casts in printk 2020-12-08 15:53:52 +01:00
verity.c btrfs: fix transaction handle leak after verity rollback failure 2021-09-17 19:29:41 +02:00
volumes.c for-5.16-tag 2021-11-01 12:48:25 -07:00
volumes.h btrfs: use btrfs_get_dev_args_from_path in dev removal ioctls 2021-10-26 19:08:07 +02:00
xattr.c btrfs: assert that extent buffers are write locked instead of only locked 2021-10-26 19:08:02 +02:00
xattr.h
zlib.c Revert "btrfs: compression: drop kmap/kunmap from zlib" 2021-10-29 13:03:05 +02:00
zoned.c btrfs: zoned: use kmemdup() to replace kmalloc + memcpy 2021-10-26 19:08:05 +02:00
zoned.h btrfs: zoned: add a dedicated data relocation block group 2021-10-26 19:08:01 +02:00
zstd.c Revert "btrfs: compression: drop kmap/kunmap from zstd" 2021-10-29 13:02:50 +02:00