linux-stable.git/include/linux/shmem_fs.h, branch v6.9.2

mm/shmem: inline shmem_is_huge() for disabled transparent hugepages

2024-04-16T22:39:51+00:00

In order to  minimize code size (CONFIG_CC_OPTIMIZE_FOR_SIZE=y),
compiler might choose to make a regular function call (out-of-line) for
shmem_is_huge() instead of inlining it. When transparent hugepages are
disabled (CONFIG_TRANSPARENT_HUGEPAGE=n), it can cause compilation
error.

mm/shmem.c: In function `shmem_getattr':
./include/linux/huge_mm.h:383:27: note: in expansion of macro `BUILD_BUG'
  383 | #define HPAGE_PMD_SIZE ({ BUILD_BUG(); 0; })
      |                           ^~~~~~~~~
mm/shmem.c:1148:33: note: in expansion of macro `HPAGE_PMD_SIZE'
 1148 |                 stat->blksize = HPAGE_PMD_SIZE;

To prevent the possible error, always inline shmem_is_huge() when
transparent hugepages are disabled.

Link: https://lkml.kernel.org/r/20240409155407.2322714-1-sumanthk@linux.ibm.com
Signed-off-by: Sumanth Korikkar 
Acked-by: David Hildenbrand 
Cc: Alexander Gordeev 
Cc: Heiko Carstens 
Cc: Hugh Dickins 
Cc: Ilya Leoshkevich 
Cc: Vasily Gorbik 
Cc: 
Signed-off-by: Andrew Morton

Merge tag 'fs_for_v6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs

2024-03-13T21:30:58+00:00

Pull ext2, isofs, udf, and quota updates from Jan Kara:
 "A lot of material this time:

   - removal of a lot of GFP_NOFS usage from ext2, udf, quota (either it
     was legacy or replaced with scoped memalloc_nofs_*() API)

   - removal of BUG_ONs in quota code

   - conversion of UDF to the new mount API

   - tightening quota on disk format verification

   - fix some potentially unsafe use of RCU pointers in quota code and
     annotate everything properly to make sparse happy

   - a few other small quota, ext2, udf, and isofs fixes"

* tag 'fs_for_v6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: (26 commits)
  udf: remove SLAB_MEM_SPREAD flag usage
  quota: remove SLAB_MEM_SPREAD flag usage
  isofs: remove SLAB_MEM_SPREAD flag usage
  ext2: remove SLAB_MEM_SPREAD flag usage
  ext2: mark as deprecated
  udf: convert to new mount API
  udf: convert novrs to an option flag
  MAINTAINERS: add missing git address for ext2 entry
  quota: Detect loops in quota tree
  quota: Properly annotate i_dquot arrays with __rcu
  quota: Fix rcu annotations of inode dquot pointers
  isofs: handle CDs with bad root inode but good Joliet root directory
  udf: Avoid invalid LVID used on mount
  quota: Fix potential NULL pointer dereference
  quota: Drop GFP_NOFS instances under dquot->dq_lock and dqio_sem
  quota: Set nofs allocation context when acquiring dqio_sem
  ext2: Remove GFP_NOFS use in ext2_xattr_cache_insert()
  ext2: Drop GFP_NOFS use in ext2_get_blocks()
  ext2: Drop GFP_NOFS allocation from ext2_init_block_alloc_info()
  udf: Remove GFP_NOFS allocation in udf_expand_file_adinicb()
  ...

shmem: move shmem_mapping out of line

2024-02-21T06:06:50+00:00

shmem_aops really should not be exported to the world.  Move
shmem_mapping and export it as internal for the one semi-legitimate
modular user in udmabuf.

This effectively reverts commit 30e6a51dbb05 ("mm/shmem.c: make
shmem_mapping() inline"). which added a bogus shmem_aops non-GPL export
for no reason whatsoever as there as no shmem_mapping call outside of
core MM code at that point.

Signed-off-by: Christoph Hellwig 
Reviewed-by: "Matthew Wilcox (Oracle)" 
Signed-off-by: Chandan Babu R

quota: Properly annotate i_dquot arrays with __rcu

2024-02-08T11:04:59+00:00

Dquots pointed to from i_dquot arrays in inodes are protected by
dquot_srcu. Annotate them as such and change .get_dquots callback to
return properly annotated pointer to make sparse happy.

Fixes: b9ba6f94b238 ("quota: remove dqptr_sem")
Signed-off-by: Jan Kara

shmem: shrink shmem_inode_info: dir_offsets in a union

2023-10-18T21:34:13+00:00

Patch series "shmem,tmpfs: general maintenance".

Mostly just cosmetic mods in mm/shmem.c, but the last two enforcing the
"size=" limit better.  8/8 goes into percpu counter territory, and could
stand alone.


This patch (of 8):

Shave 32 bytes off (the 64-bit) shmem_inode_info.  There was a 4-byte
pahole after stop_eviction, better filled by fsflags.  And the 24-byte
dir_offsets can only be used by directories, whereas shrinklist and
swaplist only by shmem_mapping() inodes (regular files or long symlinks):
so put those into a union.  No change in mm/shmem.c is required for this.

Link: https://lkml.kernel.org/r/c7441dc6-f3bb-dd60-c670-9f5cbd9f266@google.com
Link: https://lkml.kernel.org/r/86ebb4b-c571-b9e8-27f5-cb82ec50357e@google.com
Signed-off-by: Hugh Dickins 
Reviewed-by: Chuck Lever 
Reviewed-by: Jan Kara 
Cc: Axel Rasmussen 
Cc: Carlos Maiolino 
Cc: Christian Brauner 
Cc: Johannes Weiner 
Cc: Matthew Wilcox (Oracle) 
Cc: Darrick J. Wong 
Cc: Dave Chinner 
Cc: Tim Chen 
Signed-off-by: Andrew Morton

tmpfs: track free_ispace instead of free_inodes

2023-08-09T07:15:51+00:00

In preparation for assigning some inode space to extended attributes,
keep track of free_ispace instead of number of free_inodes: as if one
tmpfs inode (and accompanying dentry) occupies very approximately 1KiB.

Unsigned long is large enough for free_ispace, on 64-bit and on 32-bit:
but take care to enforce the maximum.  And fix the nr_blocks maximum on
32-bit: S64_MAX would be too big for it there, so say LONG_MAX instead.

Delete the incorrect limited<->unlimited blocks/inodes comment above
shmem_reconfigure(): leave it to the error messages below to describe.

Signed-off-by: Hugh Dickins 
Reviewed-by: Jan Kara 
Reviewed-by: Carlos Maiolino 
Message-Id: <4fe1739-d9e7-8dfd-5bce-12e7339711da@google.com>
Signed-off-by: Christian Brauner

shmem: stable directory offsets

2023-08-09T07:15:40+00:00

The current cursor-based directory offset mechanism doesn't work
when a tmpfs filesystem is exported via NFS. This is because NFS
clients do not open directories. Each server-side READDIR operation
has to open the directory, read it, then close it. The cursor state
for that directory, being associated strictly with the opened
struct file, is thus discarded after each NFS READDIR operation.

Directory offsets are cached not only by NFS clients, but also by
user space libraries on those clients. Essentially there is no way
to invalidate those caches when directory offsets have changed on
an NFS server after the offset-to-dentry mapping changes. Thus the
whole application stack depends on unchanging directory offsets.

The solution we've come up with is to make the directory offset for
each file in a tmpfs filesystem stable for the life of the directory
entry it represents.

shmem_readdir() and shmem_dir_llseek() now use an xarray to map each
directory offset (an loff_t integer) to the memory address of a
struct dentry.

Signed-off-by: Chuck Lever 
Message-Id: <168814734331.530310.3911190551060453102.stgit@manet.1015granger.net>
Signed-off-by: Christian Brauner

shmem: Add default quota limit mount options

2023-08-09T07:15:40+00:00

Allow system administrator to set default global quota limits at tmpfs
mount time.

Signed-off-by: Lukas Czerner 
Signed-off-by: Carlos Maiolino 
Reviewed-by: Jan Kara 
Message-Id: <20230725144510.253763-7-cem@kernel.org>
Signed-off-by: Christian Brauner

shmem: quota support

2023-08-09T07:15:39+00:00

Now the basic infra-structure is in place, enable quota support for tmpfs.

This offers user and group quotas to tmpfs (project quotas will be added
later). Also, as other filesystems, the tmpfs quota is not supported
within user namespaces yet, so idmapping is not translated.

Signed-off-by: Lukas Czerner 
Signed-off-by: Carlos Maiolino 
Reviewed-by: Jan Kara 
Message-Id: <20230725144510.253763-6-cem@kernel.org>
Signed-off-by: Christian Brauner

shmem: prepare shmem quota infrastructure

2023-08-09T07:15:39+00:00

Add new shmem quota format, its quota_format_ops together with
dquot_operations

Signed-off-by: Lukas Czerner 
Signed-off-by: Carlos Maiolino 
Reviewed-by: Jan Kara 
Message-Id: <20230725144510.253763-5-cem@kernel.org>
Signed-off-by: Christian Brauner