summaryrefslogtreecommitdiffstats
path: root/mm/shmem.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2024-03-13 21:52:24 +0100
committerLinus Torvalds <torvalds@linux-foundation.org>2024-03-13 21:52:24 +0100
commitbabbcc02327a14a352a7899dc603eaa064559c75 (patch)
tree9029e0240a6b748c1004120bebb3791322fe3887 /mm/shmem.c
parentMerge tag '6.9-rc-smb3-client-fixes-part1' of git://git.samba.org/sfrench/cif... (diff)
parentxfs: shrink failure needs to hold AGI buffer (diff)
downloadlinux-babbcc02327a14a352a7899dc603eaa064559c75.tar.xz
linux-babbcc02327a14a352a7899dc603eaa064559c75.zip
Merge tag 'xfs-6.9-merge-8' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull xfs updates from Chandan Babu: - Online repair updates: - More ondisk structures being repaired: - Inode's mode field by trying to obtain file type value from the a directory entry - Quota counters - Link counts of inodes - FS summary counters - Support for in-memory btrees has been added to support repair of rmap btrees - Misc changes: - Report corruption of metadata to the health tracking subsystem - Enable indirect health reporting when resources are scarce - Reduce memory usage while repairing refcount btree - Extend "Bmap update" intent item to support atomic extent swapping on the realtime device - Extend "Bmap update" intent item to support extended attribute fork and unwritten extents - Code cleanups: - Bmap log intent - Btree block pointer checking - Btree readahead - Buffer target - Symbolic link code - Remove mrlock wrapper around the rwsem - Convert all the GFP_NOFS flag usages to use the scoped memalloc_nofs_save() API instead of direct calls with the GFP_NOFS - Refactor and simplify xfile abstraction. Lower level APIs in shmem.c are required to be exported in order to achieve this - Skip checking alignment constraints for inode chunk allocations when block size is larger than inode chunk size - Do not submit delwri buffers collected during log recovery when an error has been encountered - Fix SEEK_HOLE/DATA for file regions which have active COW extents - Fix lock order inversion when executing error handling path during shrinking a filesystem - Remove duplicate ifdefs * tag 'xfs-6.9-merge-8' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (183 commits) xfs: shrink failure needs to hold AGI buffer mm/shmem.c: Use new form of *@param in kernel-doc kernel-doc: Add unary operator * to $type_param_ref xfs: use kvfree() in xlog_cil_free_logvec() xfs: xfs_btree_bload_prep_block() should use __GFP_NOFAIL xfs: fix scrub stats file permissions xfs: fix log recovery erroring out on refcount recovery failure xfs: move symlink target write function to libxfs xfs: move remote symlink target read function to libxfs xfs: move xfs_symlink_remote.c declarations to xfs_symlink_remote.h xfs: xfs_bmap_finish_one should map unwritten extents properly xfs: support deferred bmap updates on the attr fork xfs: support recovering bmap intent items targetting realtime extents xfs: add a realtime flag to the bmap update log redo items xfs: add a xattr_entry helper xfs: fix xfs_bunmapi to allow unmapping of partial rt extents xfs: move xfs_bmap_defer_add to xfs_bmap_item.c xfs: reuse xfs_bmap_update_cancel_item xfs: add a bi_entry helper xfs: remove xfs_trans_set_bmap_flags ...
Diffstat (limited to 'mm/shmem.c')
-rw-r--r--mm/shmem.c42
1 files changed, 37 insertions, 5 deletions
diff --git a/mm/shmem.c b/mm/shmem.c
index 29d5a024df48..be890844fc92 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -254,7 +254,7 @@ static void shmem_inode_unacct_blocks(struct inode *inode, long pages)
}
static const struct super_operations shmem_ops;
-const struct address_space_operations shmem_aops;
+static const struct address_space_operations shmem_aops;
static const struct file_operations shmem_file_operations;
static const struct inode_operations shmem_inode_operations;
static const struct inode_operations shmem_dir_inode_operations;
@@ -263,6 +263,12 @@ static const struct vm_operations_struct shmem_vm_ops;
static const struct vm_operations_struct shmem_anon_vm_ops;
static struct file_system_type shmem_fs_type;
+bool shmem_mapping(struct address_space *mapping)
+{
+ return mapping->a_ops == &shmem_aops;
+}
+EXPORT_SYMBOL_GPL(shmem_mapping);
+
bool vma_is_anon_shmem(struct vm_area_struct *vma)
{
return vma->vm_ops == &shmem_anon_vm_ops;
@@ -1966,6 +1972,9 @@ static int shmem_get_folio_gfp(struct inode *inode, pgoff_t index,
int error;
bool alloced;
+ if (WARN_ON_ONCE(!shmem_mapping(inode->i_mapping)))
+ return -EINVAL;
+
if (index > (MAX_LFS_FILESIZE >> PAGE_SHIFT))
return -EFBIG;
repeat:
@@ -2128,12 +2137,36 @@ unlock:
return error;
}
+/**
+ * shmem_get_folio - find, and lock a shmem folio.
+ * @inode: inode to search
+ * @index: the page index.
+ * @foliop: pointer to the folio if found
+ * @sgp: SGP_* flags to control behavior
+ *
+ * Looks up the page cache entry at @inode & @index. If a folio is
+ * present, it is returned locked with an increased refcount.
+ *
+ * If the caller modifies data in the folio, it must call folio_mark_dirty()
+ * before unlocking the folio to ensure that the folio is not reclaimed.
+ * There is no need to reserve space before calling folio_mark_dirty().
+ *
+ * When no folio is found, the behavior depends on @sgp:
+ * - for SGP_READ, *@foliop is %NULL and 0 is returned
+ * - for SGP_NOALLOC, *@foliop is %NULL and -ENOENT is returned
+ * - for all other flags a new folio is allocated, inserted into the
+ * page cache and returned locked in @foliop.
+ *
+ * Context: May sleep.
+ * Return: 0 if successful, else a negative error code.
+ */
int shmem_get_folio(struct inode *inode, pgoff_t index, struct folio **foliop,
enum sgp_type sgp)
{
return shmem_get_folio_gfp(inode, index, foliop, sgp,
mapping_gfp_mask(inode->i_mapping), NULL, NULL);
}
+EXPORT_SYMBOL_GPL(shmem_get_folio);
/*
* This is like autoremove_wake_function, but it removes the wait queue
@@ -3500,10 +3533,10 @@ static int shmem_symlink(struct mnt_idmap *idmap, struct inode *dir,
inode->i_op = &shmem_short_symlink_operations;
} else {
inode_nohighmem(inode);
+ inode->i_mapping->a_ops = &shmem_aops;
error = shmem_get_folio(inode, 0, &folio, SGP_WRITE);
if (error)
goto out_remove_offset;
- inode->i_mapping->a_ops = &shmem_aops;
inode->i_op = &shmem_symlink_inode_operations;
memcpy(folio_address(folio), symname, len);
folio_mark_uptodate(folio);
@@ -4468,7 +4501,7 @@ static int shmem_error_remove_folio(struct address_space *mapping,
return 0;
}
-const struct address_space_operations shmem_aops = {
+static const struct address_space_operations shmem_aops = {
.writepage = shmem_writepage,
.dirty_folio = noop_dirty_folio,
#ifdef CONFIG_TMPFS
@@ -4480,7 +4513,6 @@ const struct address_space_operations shmem_aops = {
#endif
.error_remove_folio = shmem_error_remove_folio,
};
-EXPORT_SYMBOL(shmem_aops);
static const struct file_operations shmem_file_operations = {
.mmap = shmem_mmap,
@@ -4835,6 +4867,7 @@ struct file *shmem_kernel_file_setup(const char *name, loff_t size, unsigned lon
{
return __shmem_file_setup(shm_mnt, name, size, flags, S_PRIVATE);
}
+EXPORT_SYMBOL_GPL(shmem_kernel_file_setup);
/**
* shmem_file_setup - get an unlinked file living in tmpfs
@@ -4912,7 +4945,6 @@ struct folio *shmem_read_folio_gfp(struct address_space *mapping,
struct folio *folio;
int error;
- BUG_ON(!shmem_mapping(mapping));
error = shmem_get_folio_gfp(inode, index, &folio, SGP_CACHE,
gfp, NULL, NULL);
if (error)