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  1. 15 3月, 2019 1 次提交
  3. 13 3月, 2019 23 次提交
    • C
      f2fs: fix to avoid deadlock in f2fs_read_inline_dir() · aadcef64
      由 Chao Yu 提交于 
      As Jiqun Li reported in bugzilla:

https://bugzilla.kernel.org/show_bug.cgi?id=202883

sometimes, dead lock when make system call SYS_getdents64 with fsync() is
called by another process.

monkey running on android9.0

1.  task 9785 held sbi->cp_rwsem and waiting lock_page()
2.  task 10349 held mm_sem and waiting sbi->cp_rwsem
3. task 9709 held lock_page() and waiting mm_sem

so this is a dead lock scenario.

task stack is show by crash tools as following

crash_arm64> bt ffffffc03c354080
PID: 9785   TASK: ffffffc03c354080  CPU: 1   COMMAND: "RxIoScheduler-3"
>> #7 [ffffffc01b50fac0] __lock_page at ffffff80081b11e8

crash-arm64> bt 10349
PID: 10349  TASK: ffffffc018b83080  CPU: 1   COMMAND: "BUGLY_ASYNC_UPL"
>> #3 [ffffffc01f8cfa40] rwsem_down_read_failed at ffffff8008a93afc
     PC: 00000033  LR: 00000000  SP: 00000000  PSTATE: ffffffffffffffff

crash-arm64> bt 9709
PID: 9709   TASK: ffffffc03e7f3080  CPU: 1   COMMAND: "IntentService[A"
>> #3 [ffffffc001e67850] rwsem_down_read_failed at ffffff8008a93afc
>> #8 [ffffffc001e67b80] el1_ia at ffffff8008084fc4
     PC: ffffff8008274114  [compat_filldir64+120]
     LR: ffffff80083584d4  [f2fs_fill_dentries+448]
     SP: ffffffc001e67b80  PSTATE: 80400145
    X29: ffffffc001e67b80  X28: 0000000000000000  X27: 000000000000001a
    X26: 00000000000093d7  X25: ffffffc070d52480  X24: 0000000000000008
    X23: 0000000000000028  X22: 00000000d43dfd60  X21: ffffffc001e67e90
    X20: 0000000000000011  X19: ffffff80093a4000  X18: 0000000000000000
    X17: 0000000000000000  X16: 0000000000000000  X15: 0000000000000000
    X14: ffffffffffffffff  X13: 0000000000000008  X12: 0101010101010101
    X11: 7f7f7f7f7f7f7f7f  X10: 6a6a6a6a6a6a6a6a   X9: 7f7f7f7f7f7f7f7f
     X8: 0000000080808000   X7: ffffff800827409c   X6: 0000000080808000
     X5: 0000000000000008   X4: 00000000000093d7   X3: 000000000000001a
     X2: 0000000000000011   X1: ffffffc070d52480   X0: 0000000000800238
>> #9 [ffffffc001e67be0] f2fs_fill_dentries at ffffff80083584d0
     PC: 0000003c  LR: 00000000  SP: 00000000  PSTATE: 000000d9
    X12: f48a02ff X11: d4678960 X10: d43dfc00  X9: d4678ae4
     X8: 00000058  X7: d4678994  X6: d43de800  X5: 000000d9
     X4: d43dfc0c  X3: d43dfc10  X2: d46799c8  X1: 00000000
     X0: 00001068

Below potential deadlock will happen between three threads:
Thread A		Thread B		Thread C
- f2fs_do_sync_file
 - f2fs_write_checkpoint
  - down_write(&sbi->node_change) -- 1)
			- do_page_fault
			 - down_write(&mm->mmap_sem) -- 2)
			  - do_wp_page
			   - f2fs_vm_page_mkwrite
						- getdents64
						 - f2fs_read_inline_dir
						  - lock_page -- 3)
  - f2fs_sync_node_pages
   - lock_page -- 3)
			    - __do_map_lock
			     - down_read(&sbi->node_change) -- 1)
						  - f2fs_fill_dentries
						   - dir_emit
						    - compat_filldir64
						     - do_page_fault
						      - down_read(&mm->mmap_sem) -- 2)

Since f2fs_readdir is protected by inode.i_rwsem, there should not be
any updates in inode page, we're safe to lookup dents in inode page
without its lock held, so taking off the lock to improve concurrency
of readdir and avoid potential deadlock.
Reported-by: NJiqun Li <jiqun.li@unisoc.com>
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>
      aadcef64
    • C
      f2fs: fix to adapt small inline xattr space in __find_inline_xattr() · 2c28aba8
      由 Chao Yu 提交于 
      With below testcase, we will fail to find existed xattr entry:

1. mkfs.f2fs -O extra_attr -O flexible_inline_xattr /dev/zram0
2. mount -t f2fs -o inline_xattr_size=1 /dev/zram0 /mnt/f2fs/
3. touch /mnt/f2fs/file
4. setfattr -n "user.name" -v 0 /mnt/f2fs/file
5. getfattr -n "user.name" /mnt/f2fs/file

/mnt/f2fs/file: user.name: No such attribute

The reason is for inode which has very small inline xattr size,
__find_inline_xattr() will fail to traverse any entry due to first
entry may not be loaded from xattr node yet, later, we may skip to
check entire xattr datas in __find_xattr(), result in such wrong
condition.

This patch adds condition to check such case to avoid this issue.
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>
      2c28aba8
    • C
      f2fs: fix to do sanity check with inode.i_inline_xattr_size · dd6c89b5
      由 Chao Yu 提交于 
      As Paul Bandha reported in bugzilla:

https://bugzilla.kernel.org/show_bug.cgi?id=202709

When I run the poc on the mounted f2fs img I get a buffer overflow in
read_inline_xattr due to there being no sanity check on the value of
i_inline_xattr_size.

I created the img by just modifying the value of i_inline_xattr_size
in the inode:

i_name                        		[test1.txt]
i_ext: fofs:0 blkaddr:0 len:0
i_extra_isize                 		[0x      18 : 24]
i_inline_xattr_size           		[0x    ffff : 65535]
i_addr[ofs]                   		[0x       0 : 0]

mkdir /mnt/f2fs
mount ./f2fs1.img /mnt/f2fs
gcc poc.c -o poc
./poc

int main() {
	int y = syscall(SYS_listxattr, "/mnt/f2fs/test1.txt", NULL, 0);
	printf("ret %d", y);
	printf("errno: %d\n", errno);

}

 BUG: KASAN: slab-out-of-bounds in read_inline_xattr+0x18f/0x260
 Read of size 262140 at addr ffff88011035efd8 by task f2fs1poc/3263

 CPU: 0 PID: 3263 Comm: f2fs1poc Not tainted 4.18.0-custom #1
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.1-0-g0551a4be2c-prebuilt.qemu-project.org 04/01/2014
 Call Trace:
  dump_stack+0x71/0xab
  print_address_description+0x83/0x250
  kasan_report+0x213/0x350
  memcpy+0x1f/0x50
  read_inline_xattr+0x18f/0x260
  read_all_xattrs+0xba/0x190
  f2fs_listxattr+0x9d/0x3f0
  listxattr+0xb2/0xd0
  path_listxattr+0x93/0xe0
  do_syscall_64+0x9d/0x220
  entry_SYSCALL_64_after_hwframe+0x44/0xa9

Let's add sanity check for inode.i_inline_xattr_size during f2fs_iget()
to avoid this issue.
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>
      dd6c89b5
    • J
      f2fs: give some messages for inline_xattr_size · 70db5b04
      由 Jaegeuk Kim 提交于 
      This patch adds some kernel messages when user sets wrong inline_xattr_size.

Fixes: 500e0b28 ("f2fs: fix to check inline_xattr_size boundary correctly")
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>
      70db5b04
    • C
      f2fs: don't trigger read IO for beyond EOF page · 86109c90
      由 Chao Yu 提交于 
      In f2fs_mpage_readpages(), if page is beyond EOF, we should just
zero out it, but previously, before checking previous mapping
info, we missed to check filesize boundary, fix it.
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>
      86109c90
    • C
      f2fs: fix to add refcount once page is tagged PG_private · 240a5915
      由 Chao Yu 提交于 
      As Gao Xiang reported in bugzilla:

https://bugzilla.kernel.org/show_bug.cgi?id=202749

f2fs may skip pageout() due to incorrect page reference count.

The problem here is that MM defined the rule [1] very clearly that
once page was set with PG_private flag, we should increment the
refcount in that page, also main flows like pageout(), migrate_page()
will assume there is one additional page reference count if
page_has_private() returns true.

But currently, f2fs won't add/del refcount when changing PG_private
flag. Anyway, f2fs should follow MM's rule to make MM's related flows
running as expected.

[1] https://lore.kernel.org/lkml/2b19b3c4-2bc4-15fa-15cc-27a13e5c7af1@aol.com/Reported-by: NGao Xiang <gaoxiang25@huawei.com>
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>
      240a5915
    • C
      f2fs: remove wrong comment in f2fs_invalidate_page() · 25720cc0
      由 Chao Yu 提交于 
      Since 8c242db9 ("f2fs: fix stale ATOMIC_WRITTEN_PAGE private pointer"),
we've started to not skip clear private flag for atomic_write page
truncation, so removing old wrong comment in f2fs_invalidate_page().
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>
      25720cc0
    • C
      f2fs: fix to use kvfree instead of kzfree · 2a6a7e72
      由 Chao Yu 提交于 
      As Jiqun Li reported in bugzilla:

https://bugzilla.kernel.org/show_bug.cgi?id=202747

System can panic due to using wrong allocate/free function pair
in xattr interface:
- use kvmalloc to allocate memory
- use kzfree to free memory

Let's fix to use kvfree instead of kzfree, BTW, we are safe to
get rid of kzfree, since there is no such confidential data stored
as xattr, we don't need to zero it before free memory.

Fixes: 5222595d ("f2fs: use kvmalloc, if kmalloc is failed")
Reported-by: NJiqun Li <jiqun.li@unisoc.com>
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>
      2a6a7e72
    • C
      f2fs: trace f2fs_ioc_shutdown · 559e87c4
      由 Chao Yu 提交于 
      This patch supports to trace f2fs_ioc_shutdown.
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>
      559e87c4
    • C
      f2fs: fix to avoid deadlock of atomic file operations · 48432984
      由 Chao Yu 提交于 
      Thread A				Thread B
- __fput
 - f2fs_release_file
  - drop_inmem_pages
   - mutex_lock(&fi->inmem_lock)
   - __revoke_inmem_pages
    - lock_page(page)
					- open
					- f2fs_setattr
					- truncate_setsize
					 - truncate_inode_pages_range
					  - lock_page(page)
					  - truncate_cleanup_page
					   - f2fs_invalidate_page
					    - drop_inmem_page
					    - mutex_lock(&fi->inmem_lock);

We may encounter above ABBA deadlock as reported by Kyungtae Kim:

I'm reporting a bug in linux-4.17.19: "INFO: task hung in
drop_inmem_page" (no reproducer)

I think this might be somehow related to the following:
https://groups.google.com/forum/#!searchin/syzkaller-bugs/INFO$3A$20task$20hung$20in$20%7Csort:date/syzkaller-bugs/c6soBTrdaIo/AjAzPeIzCgAJ

=========================================
INFO: task syz-executor7:10822 blocked for more than 120 seconds.
      Not tainted 4.17.19 #1
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor7   D27024 10822   6346 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2867 [inline]
 __schedule+0x721/0x1e60 kernel/sched/core.c:3515
 schedule+0x88/0x1c0 kernel/sched/core.c:3559
 schedule_preempt_disabled+0x18/0x30 kernel/sched/core.c:3617
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x5bd/0x1410 kernel/locking/mutex.c:893
 mutex_lock_nested+0x1b/0x20 kernel/locking/mutex.c:908
 drop_inmem_page+0xcb/0x810 fs/f2fs/segment.c:327
 f2fs_invalidate_page+0x337/0x5e0 fs/f2fs/data.c:2401
 do_invalidatepage mm/truncate.c:165 [inline]
 truncate_cleanup_page+0x261/0x330 mm/truncate.c:187
 truncate_inode_pages_range+0x552/0x1610 mm/truncate.c:367
 truncate_inode_pages mm/truncate.c:478 [inline]
 truncate_pagecache+0x6d/0x90 mm/truncate.c:801
 truncate_setsize+0x81/0xa0 mm/truncate.c:826
 f2fs_setattr+0x44f/0x1270 fs/f2fs/file.c:781
 notify_change+0xa62/0xe80 fs/attr.c:313
 do_truncate+0x12e/0x1e0 fs/open.c:63
 do_last fs/namei.c:2955 [inline]
 path_openat+0x2042/0x29f0 fs/namei.c:3505
 do_filp_open+0x1bd/0x2c0 fs/namei.c:3540
 do_sys_open+0x35e/0x4e0 fs/open.c:1101
 __do_sys_open fs/open.c:1119 [inline]
 __se_sys_open fs/open.c:1114 [inline]
 __x64_sys_open+0x89/0xc0 fs/open.c:1114
 do_syscall_64+0xc4/0x4e0 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4497b9
RSP: 002b:00007f734e459c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007f734e45a6cc RCX: 00000000004497b9
RDX: 0000000000000104 RSI: 00000000000a8280 RDI: 0000000020000080
RBP: 000000000071bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000007230 R14: 00000000006f02d0 R15: 00007f734e45a700
INFO: task syz-executor7:10858 blocked for more than 120 seconds.
      Not tainted 4.17.19 #1
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor7   D28880 10858   6346 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2867 [inline]
 __schedule+0x721/0x1e60 kernel/sched/core.c:3515
 schedule+0x88/0x1c0 kernel/sched/core.c:3559
 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:565 [inline]
 rwsem_down_write_failed+0x5e6/0xc90 kernel/locking/rwsem-xadd.c:594
 call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:117
 __down_write arch/x86/include/asm/rwsem.h:142 [inline]
 down_write+0x58/0xa0 kernel/locking/rwsem.c:72
 inode_lock include/linux/fs.h:713 [inline]
 do_truncate+0x120/0x1e0 fs/open.c:61
 do_last fs/namei.c:2955 [inline]
 path_openat+0x2042/0x29f0 fs/namei.c:3505
 do_filp_open+0x1bd/0x2c0 fs/namei.c:3540
 do_sys_open+0x35e/0x4e0 fs/open.c:1101
 __do_sys_open fs/open.c:1119 [inline]
 __se_sys_open fs/open.c:1114 [inline]
 __x64_sys_open+0x89/0xc0 fs/open.c:1114
 do_syscall_64+0xc4/0x4e0 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4497b9
RSP: 002b:00007f734e3b4c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007f734e3b56cc RCX: 00000000004497b9
RDX: 0000000000000104 RSI: 00000000000a8280 RDI: 0000000020000080
RBP: 000000000071c238 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000007230 R14: 00000000006f02d0 R15: 00007f734e3b5700
INFO: task syz-executor5:10829 blocked for more than 120 seconds.
      Not tainted 4.17.19 #1
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor5   D28760 10829   6308 0x80000002
Call Trace:
 context_switch kernel/sched/core.c:2867 [inline]
 __schedule+0x721/0x1e60 kernel/sched/core.c:3515
 schedule+0x88/0x1c0 kernel/sched/core.c:3559
 io_schedule+0x21/0x80 kernel/sched/core.c:5179
 wait_on_page_bit_common mm/filemap.c:1100 [inline]
 __lock_page+0x2b5/0x390 mm/filemap.c:1273
 lock_page include/linux/pagemap.h:483 [inline]
 __revoke_inmem_pages+0xb35/0x11c0 fs/f2fs/segment.c:231
 drop_inmem_pages+0xa3/0x3e0 fs/f2fs/segment.c:306
 f2fs_release_file+0x2c7/0x330 fs/f2fs/file.c:1556
 __fput+0x2c7/0x780 fs/file_table.c:209
 ____fput+0x1a/0x20 fs/file_table.c:243
 task_work_run+0x151/0x1d0 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0x8ba/0x30a0 kernel/exit.c:865
 do_group_exit+0x13b/0x3a0 kernel/exit.c:968
 get_signal+0x6bb/0x1650 kernel/signal.c:2482
 do_signal+0x84/0x1b70 arch/x86/kernel/signal.c:810
 exit_to_usermode_loop+0x155/0x190 arch/x86/entry/common.c:162
 prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:265 [inline]
 do_syscall_64+0x445/0x4e0 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4497b9
RSP: 002b:00007f1c68e74ce8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 000000000071bf80 RCX: 00000000004497b9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000071bf80
RBP: 000000000071bf80 R08: 0000000000000000 R09: 000000000071bf58
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f1c68e759c0 R15: 00007f1c68e75700

This patch tries to use trylock_page to mitigate such deadlock condition
for fix.
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>
      48432984
    • C
      f2fs: fix to dirty inode for i_mode recovery · ca597bdd
      由 Chao Yu 提交于 
      As Seulbae Kim reported in bugzilla:

https://bugzilla.kernel.org/show_bug.cgi?id=202637

We didn't recover permission field correctly after sudden power-cut,
the reason is in setattr we didn't add inode into global dirty list
once i_mode is changed, so latter checkpoint triggered by fsync will
not flush last i_mode into disk, result in this problem, fix it.
Reported-by: NSeulbae Kim <seulbae@gatech.edu>
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>
      ca597bdd
    • J
      f2fs: give random value to i_generation · 428e3bcf
      由 Jaegeuk Kim 提交于 
      This follows to give random number to i_generation along with commit
23253068 ("ext4: improve smp scalability for inode generation")

This can be used for DUN for UFS HW encryption.
Reviewed-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>
      428e3bcf
    • G
      f2fs: no need to take page lock in readdir · 613f3dcd
      由 Gao Xiang 提交于 
      VFS will take inode_lock for readdir, therefore no need to
take page lock in readdir at all just as the majority of
other generic filesystems.

This patch improves concurrency since .iterate_shared
was introduced to VFS years ago.
Signed-off-by: NGao Xiang <gaoxiang25@huawei.com>
Reviewed-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>
      613f3dcd
    • C
      f2fs: fix to update iostat correctly in IPU path · e46f6bd8
      由 Chao Yu 提交于 
      In error path of IPU, we didn't account iostat correctly, fix it.
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>
      e46f6bd8
    • C
      f2fs: fix encrypted page memory leak · 6492a335
      由 Chao Yu 提交于 
      For IPU path of f2fs_do_write_data_page(), in its error path, we
need to release encrypted page and fscrypt context, otherwise it
will cause memory leak.
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>
      6492a335
    • C
      f2fs: make fault injection covering __submit_flush_wait() · dc37910d
      由 Chao Yu 提交于 
      This patch changes to allow failure of f2fs_bio_alloc() in
__submit_flush_wait(), which can simulate flush error in checkpoint()
for covering more error paths.
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>
      dc37910d
    • C
      f2fs: fix to retry fill_super only if recovery failed · aa2c8c43
      由 Chao Yu 提交于 
      With current retry mechanism in f2fs_fill_super, first fill_super
fails due to no memory, then second fill_super runs w/o recovery,
if we succeed, we may lose fsynced data, it doesn't make sense.

Let's retry fill_super only if it occurs non-ENOMEM error during
recovery.
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>
      aa2c8c43
    • G
      f2fs: silence VM_WARN_ON_ONCE in mempool_alloc · bc73a4b2
      由 Gao Xiang 提交于 
      Note that __GFP_ZERO is not supported for mempool_alloc,
which also documented in the mempool_alloc comments.
Signed-off-by: NGao Xiang <gaoxiang25@huawei.com>
Reviewed-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>
      bc73a4b2
    • J
      f2fs: fix wrong #endif · 0af725fc
      由 Jaegeuk Kim 提交于 
      We have to cover whole headerfile with last #endif.
Reviewed-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>
      0af725fc
    • K
      proc: commit to genradix · 94f8f3b0
      由 Kent Overstreet 提交于 
      The new generic radix trees have a simpler API and implementation, and
no limitations on number of elements, so all flex_array users are being
converted

Link: http://lkml.kernel.org/r/20181217131929.11727-6-kent.overstreet@gmail.comSigned-off-by: NKent Overstreet <kent.overstreet@gmail.com>
Reviewed-by: NAlexey Dobriyan <adobriyan@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Eric Paris <eparis@parisplace.org>
Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: Paul Moore <paul@paul-moore.com>
Cc: Pravin B Shelar <pshelar@ovn.org>
Cc: Shaohua Li <shli@kernel.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      94f8f3b0
    • A
      proc: calculate end pointer for /proc/*/* lookup at compile time · d5a572a4
      由 Alexey Dobriyan 提交于 
      Compilers like to transform loops like

	for (i = 0; i < n; i++) {
		[use p[i]]
	}

into
	for (p = p0; p < end; p++) {
		...
	}

Do it by hand, so that it results in overall simpler loop
and smaller code.

Space savings:

	$ ./scripts/bloat-o-meter ../vmlinux-001 ../obj/vmlinux
	add/remove: 0/0 grow/shrink: 2/1 up/down: 4/-9 (-5)
	Function                                     old     new   delta
	proc_tid_base_lookup                          17      19      +2
	proc_tgid_base_lookup                         17      19      +2
	proc_pident_lookup                           179     170      -9

The same could be done to proc_pident_readdir(), but the code becomes
bigger for some reason.

[sfr@canb.auug.org.au: merge fix for proc_pident_lookup() API change]
  Link: http://lkml.kernel.org/r/20190131160135.4a8ae70b@canb.auug.org.au
Link: http://lkml.kernel.org/r/20190114200422.GB9680@avx2Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Cc: James Morris <jmorris@namei.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Casey Schaufler <casey@schaufler-ca.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      d5a572a4
    • N
      mm: refactor readahead defines in mm.h · b5420237
      由 Nikolay Borisov 提交于 
      All users of VM_MAX_READAHEAD actually convert it to kbytes and then to
pages. Define the macro explicitly as (SZ_128K / PAGE_SIZE). This
simplifies the expression in every filesystem. Also rename the macro to
VM_READAHEAD_PAGES to properly convey its meaning. Finally remove unused
VM_MIN_READAHEAD

[akpm@linux-foundation.org: fix fs/io_uring.c, per Stephen]
Link: http://lkml.kernel.org/r/20181221144053.24318-1-nborisov@suse.comSigned-off-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NMatthew Wilcox <willy@infradead.org>
Reviewed-by: NDavid Hildenbrand <david@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Cc: Dominique Martinet <asmadeus@codewreck.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Chris Mason <clm@fb.com>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: David Sterba <dsterba@suse.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      b5420237
    • C
      hpfs: fix spelling mistake "partion" -> "partition" · cb1d150d
      由 Colin Ian King 提交于 
      Trivial fix to spelling mistakes in comments
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Signed-off-by: NMikulas Patocka <mikulas@twibright.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      cb1d150d
  5. 09 3月, 2019 1 次提交
    • N
      nfsd: allow nfsv3 readdir request to be larger. · f875a792
      由 NeilBrown 提交于 
      nfsd currently reports the NFSv3 dtpref FSINFO parameter
to be PAGE_SIZE, so NFS clients will typically ask for one
page of directory entries at a time.  This is needlessly restrictive
as nfsd can handle larger replies easily.

Also, a READDIR request (but not a READDIRPLUS request) has the count
size clipped to PAGE_SIE, again unnecessary.

This patch lifts these limits so that larger readdir requests can be
used.
Signed-off-by: NNeilBrown <neilb@suse.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>
      f875a792
  7. 08 3月, 2019 15 次提交