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ca0ac8dfd3
linux/fs
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Fabio M. De Francesco ca0ac8dfd3 hfs: replace kmap() with kmap_local_page() in bnode.c 
kmap() is being deprecated in favor of kmap_local_page().

Two main problems with kmap(): (1) It comes with an overhead as mapping
space is restricted and protected by a global lock for synchronization and
(2) it also requires global TLB invalidation when the kmap's pool wraps
and it might block when the mapping space is fully utilized until a slot
becomes available.

With kmap_local_page() the mappings are per thread, CPU local, can take
page faults, and can be called from any context (including interrupts). 
It is faster than kmap() in kernels with HIGHMEM enabled.  Furthermore,
the tasks can be preempted and, when they are scheduled to run again, the
kernel virtual addresses are restored and still valid.

Since its use in bnode.c is safe everywhere, it should be preferred.

Therefore, replace kmap() with kmap_local_page() in bnode.c.  Where
possible, use the suited standard helpers (memzero_page(), memcpy_page())
instead of open coding kmap_local_page() plus memset() or memcpy().

Tested in a QEMU/KVM x86_32 VM, 6GB RAM, booting a kernel with
HIGHMEM64GB enabled.

Link: https://lkml.kernel.org/r/20220821180400.8198-3-fmdefrancesco@gmail.com
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Suggested-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Viacheslav Dubeyko <slava@dubeyko.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Chaitanya Kulkarni <kch@nvidia.com>
Cc: Christian Brauner (Microsoft) <brauner@kernel.org>
Cc: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Kees Cook <keescook@chromium.org>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 21:55:08 -07:00
..
9p 9p: Fix some kernel-doc comments 2022-07-02 18:52:21 +09:00
adfs fs: Convert block_read_full_page() to block_read_full_folio() 2022-05-09 16:21:44 -04:00
affs affs: use memcpy_to_page and remove replace kmap_atomic() 2022-08-01 19:53:31 +02:00
afs afs: Enable multipage folio support 2022-08-13 17:20:51 -07:00
autofs autofs: remove unused ino field inode 2022-07-17 17:31:42 -07:00
befs befs: Convert befs_symlink_read_folio() to use a folio 2022-08-02 12:34:03 -04:00
bfs fs: Convert block_read_full_page() to block_read_full_folio() 2022-05-09 16:21:44 -04:00
btrfs for-6.0-rc3-tag 2022-08-28 10:44:04 -07:00
cachefiles cachefiles: narrow the scope of flushed requests when releasing fd 2022-07-05 16:12:21 +01:00
ceph We have a good pile of various fixes and cleanups from Xiubo, Jeff, 2022-08-11 12:41:07 -07:00
cifs cifs: Add helper function to check smb1+ server 2022-08-24 22:30:09 -05:00
coda coda: Convert coda_symlink_filler() to use a folio 2022-08-02 12:34:03 -04:00
configfs
cramfs cramfs: read_mapping_page() is synchronous 2022-08-02 12:34:02 -04:00
crypto We have a good pile of various fixes and cleanups from Xiubo, Jeff, 2022-08-11 12:41:07 -07:00
debugfs
devpts
dlm fs: dlm: move kref_put assert for lkb structs 2022-08-01 09:31:46 -05:00
ecryptfs ecryptfs: Convert ecryptfs to read_folio 2022-05-09 16:21:45 -04:00
efivarfs efi: vars: Move efivar caching layer into efivarfs 2022-06-24 20:40:19 +02:00
efs efs: Convert efs symlinks to read_folio 2022-05-09 16:21:45 -04:00
erofs - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe 2022-08-05 16:32:45 -07:00
exfat exfat: Drop superfluous new line for error messages 2022-08-01 10:14:07 +09:00
exportfs exportfs: support idmapped mounts 2022-04-28 16:31:10 +02:00
ext2 - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe 2022-08-05 16:32:45 -07:00
ext4 - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe 2022-08-05 16:32:45 -07:00
f2fs f2fs-for-6.0 2022-08-08 11:18:31 -07:00
fat Updates to various subsystems which I help look after. lib, ocfs2, 2022-08-07 10:03:24 -07:00
freevxfs freevxfs: Convert vxfs_immed_read_folio() to use a folio 2022-08-02 12:34:03 -04:00
fscache fscache: add tracepoint when failing cookie 2022-08-09 14:13:59 +01:00
fuse iov_iter stuff, part 2, rebased 2022-08-08 20:04:35 -07:00
gfs2 New code for 6.0: 2022-08-11 13:11:49 -07:00
hfs hfs: replace kmap() with kmap_local_page() in bnode.c 2022-09-11 21:55:08 -07:00
hfsplus hfsplus: convert kmap() to kmap_local_page() in btree.c 2022-09-11 21:55:05 -07:00
hostfs hostfs: Handle page write errors correctly 2022-08-02 12:34:02 -04:00
hpfs hpfs: Convert symlinks to read_folio 2022-05-09 16:21:45 -04:00
hugetlbfs iov_iter stuff, part 2, rebased 2022-08-08 20:04:35 -07:00
iomap New code for 6.0: 2022-08-11 13:11:49 -07:00
isofs fs/isofs: replace kmap() with kmap_local_page() 2022-09-11 21:55:05 -07:00
jbd2 - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe 2022-08-05 16:32:45 -07:00
jffs2 This pull request contains fixes for JFFS2, UBI and UBIFS 2022-06-03 14:42:24 -07:00
jfs Folio changes for 6.0 2022-08-03 10:35:43 -07:00
kernfs kernfs: Fix typo 'the the' in comment 2022-07-28 10:57:25 +02:00
ksmbd ksmbd: don't remove dos attribute xattr on O_TRUNC open 2022-08-15 21:07:01 -05:00
lockd lockd: detect and reject lock arguments that overflow 2022-08-04 10:28:48 -04:00
minix fs: Convert block_read_full_page() to block_read_full_folio() 2022-05-09 16:21:44 -04:00
netfs netfs: do not unlock and put the folio twice 2022-07-14 10:10:12 +02:00
nfs NFS client bugfixes for Linux 6.0 2022-08-22 11:40:01 -07:00
nfs_common
nfsd NFSD 6.0 Release Notes 2022-08-09 14:56:49 -07:00
nilfs2 Folio changes for 6.0 2022-08-03 10:35:43 -07:00
nls
notify fsnotify: Fix comment typo 2022-07-26 13:38:47 +02:00
ntfs Folio changes for 6.0 2022-08-03 10:35:43 -07:00
ntfs3 fs.idmapped.fixes.v6.0-rc3 2022-08-22 11:33:02 -07:00
ocfs2 ocfs2: fix freeing uninitialized resource on ocfs2_dlm_shutdown 2022-08-28 14:02:45 -07:00
omfs fs: Convert block_read_full_page() to block_read_full_folio() 2022-05-09 16:21:44 -04:00
openpromfs fs: allocate inode by using alloc_inode_sb() 2022-03-22 15:57:03 -07:00
orangefs orangefs: Remove test for folio error 2022-06-29 08:51:07 -04:00
overlayfs acl: handle idmapped mounts for idmapped filesystems 2022-08-17 11:23:31 +02:00
proc mm/smaps: don't access young/dirty bit if pte unpresent 2022-08-20 15:17:45 -07:00
pstore EFI updates for v5.20 2022-08-03 14:38:02 -07:00
qnx4 fs: Convert block_read_full_page() to block_read_full_folio() 2022-05-09 16:21:44 -04:00
qnx6 fs/qnx6: delete unnecessary checks before brelse() 2022-09-11 21:55:07 -07:00
quota - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe 2022-08-05 16:32:45 -07:00
ramfs
reiserfs Folio changes for 6.0 2022-08-03 10:35:43 -07:00
romfs romfs: Convert romfs to read_folio 2022-05-09 16:21:46 -04:00
smbfs_common Add various fsctl structs 2022-05-23 20:24:12 -05:00
squashfs squashfs: don't call kmalloc in decompressors 2022-08-28 14:02:45 -07:00
sysfs kobject: kobj_type: remove default_attrs 2022-04-05 15:39:19 +02:00
sysv Not a lot of material this cycle. Many singleton patches against various 2022-05-27 11:22:03 -07:00
tracefs tracefs: Fix syntax errors in comments 2022-06-17 19:01:28 -04:00
ubifs - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe 2022-08-05 16:32:45 -07:00
udf fs/buffer: Combine two submit_bh() and ll_rw_block() arguments 2022-07-14 12:14:32 -06:00
ufs Folio changes for 6.0 2022-08-03 10:35:43 -07:00
unicode
vboxsf vboxsf: Convert vboxsf to read_folio 2022-05-09 16:21:46 -04:00
verity fs-verity: mention btrfs support 2022-07-15 23:42:30 -07:00
xfs New code for 6.0: 2022-08-13 13:50:11 -07:00
zonefs New code for 6.0: 2022-08-11 13:11:49 -07:00
aio.c aio: use atomic_try_cmpxchg in __get_reqs_available 2022-09-11 21:55:08 -07:00
anon_inodes.c
attr.c vfs: Check the truncate maximum size in inode_newsize_ok() 2022-08-08 10:39:29 -07:00
bad_inode.c
binfmt_aout.c
binfmt_elf_fdpic.c coredump: Snapshot the vmas in do_coredump 2022-03-08 12:55:29 -06:00
binfmt_elf_test.c
binfmt_elf.c revert "fs/binfmt_elf: use PT_LOAD p_align values for static PIE" 2022-04-15 14:49:56 -07:00
binfmt_flat.c binfmt_flat: Remove shared library support 2022-04-22 10:57:18 -07:00
binfmt_misc.c
binfmt_script.c
buffer.c buffer: use try_cmpxchg in discard_buffer 2022-09-11 21:55:07 -07:00
char_dev.c
compat_binfmt_elf.c
coredump.c fs: do not compare against ->llseek 2022-07-16 09:19:15 -04:00
d_path.c
dax.c - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe 2022-08-05 16:32:45 -07:00
dcache.c dcache: move the DCACHE_OP_COMPARE case out of the __d_lookup_rcu loop 2022-08-17 14:33:03 -07:00
direct-io.c iov_iter: advancing variants of iov_iter_get_pages{,_alloc}() 2022-08-08 22:37:22 -04:00
drop_caches.c
eventfd.c
eventpoll.c epoll: use try_cmpxchg in list_add_tail_lockless 2022-09-11 21:55:07 -07:00
exec.c execve fix for v6.0-rc2 2022-08-19 14:02:24 -07:00
fcntl.c keep iocb_flags() result cached in struct file 2022-06-10 16:10:23 -04:00
fhandle.c
file_table.c iov_iter work, part 1 - isolated cleanups and optimizations. 2022-08-03 13:50:22 -07:00
file.c fix the breakage in close_fd_get_file() calling conventions change 2022-06-05 15:03:03 -04:00
filesystems.c
fs_context.c
fs_parser.c
fs_pin.c
fs_struct.c
fs_types.c
fs-writeback.c writeback: avoid use-after-free after removing device 2022-08-28 14:02:43 -07:00
fsopen.c uninline may_mount() and don't opencode it in fspick(2)/fsopen(2) 2022-05-19 23:25:10 -04:00
init.c
inode.c fs: __file_remove_privs(): restore call to inode_has_no_xattr() 2022-08-18 09:39:33 +02:00
internal.h Cleanups (and one fix) around struct mount handling. 2022-06-04 19:00:05 -07:00
ioctl.c Fixes for 5.18-rc1: 2022-04-01 19:35:56 -07:00
Kconfig mm: hugetlb_vmemmap: introduce the name HVO 2022-08-08 18:06:42 -07:00
Kconfig.binfmt m68knommu: changes for linux 5.19 2022-05-30 10:56:18 -07:00
kernel_read_file.c fs/kernel_read_file: allow to read files up-to ssize_t 2022-06-16 19:58:21 -07:00
libfs.c fs: Convert simple_readpage to simple_read_folio 2022-05-09 16:21:44 -04:00
locks.c locks: Fix dropped call to ->fl_release_private() 2022-08-17 15:08:58 -04:00
Makefile io_uring: move to separate directory 2022-07-24 18:39:10 -06:00
mbcache.c - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe 2022-08-05 16:32:45 -07:00
mount.h switch try_to_unlazy_next() to __legitimize_mnt() 2022-07-05 16:18:21 -04:00
mpage.c Folio changes for 6.0 2022-08-03 10:35:43 -07:00
namei.c fs.setgid.v6.0 2022-08-09 09:52:28 -07:00
namespace.c fs: require CAP_SYS_ADMIN in target namespace for idmapped mounts 2022-08-17 11:27:11 +02:00
no-block.c
nsfs.c
open.c iov_iter work, part 1 - isolated cleanups and optimizations. 2022-08-03 13:50:22 -07:00
pipe.c Not a lot of material this cycle. Many singleton patches against various 2022-05-27 11:22:03 -07:00
pnode.c
pnode.h
posix_acl.c acl: handle idmapped mounts for idmapped filesystems 2022-08-17 11:23:31 +02:00
proc_namespace.c vfs: escape hash as well 2022-06-28 13:58:05 -04:00
read_write.c switch new_sync_{read,write}() to ITER_UBUF 2022-08-08 22:37:15 -04:00
readdir.c
remap_range.c - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe 2022-08-05 16:32:45 -07:00
select.c
seq_file.c rxrpc: Fix locking issue 2022-05-22 21:03:01 +01:00
signalfd.c
splice.c iter_to_pipe(): switch to advancing variant of iov_iter_get_pages() 2022-08-08 22:37:23 -04:00
stack.c
stat.c RISC-V Patches for the 5.19 Merge Window, Part 1 2022-05-31 14:10:54 -07:00
statfs.c
super.c fuse update for 6.0 2022-08-08 11:10:02 -07:00
sync.c riscv: compat: syscall: Add compat_sys_call_table implementation 2022-04-26 13:36:25 -07:00
sysctls.c
timerfd.c
userfaultfd.c mm/uffd: reset write protection when unregister with wp-mode 2022-08-20 15:17:45 -07:00
utimes.c
xattr.c acl: move idmapped mount fixup into vfs_{g,s}etxattr() 2022-07-15 22:08:59 +02:00