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-rw-r--r--Documentation/filesystems/Locking38
1 files changed, 22 insertions, 16 deletions
diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking
index 8e2da1e..f48e0c6 100644
--- a/Documentation/filesystems/Locking
+++ b/Documentation/filesystems/Locking
@@ -9,7 +9,7 @@ be able to use diff(1).
--------------------------- dentry_operations --------------------------
prototypes:
- int (*d_revalidate)(struct dentry *, struct nameidata *);
+ int (*d_revalidate)(struct dentry *, unsigned int);
int (*d_hash)(const struct dentry *, const struct inode *,
struct qstr *);
int (*d_compare)(const struct dentry *, const struct inode *,
@@ -37,9 +37,8 @@ d_manage: no no yes (ref-walk) maybe
--------------------------- inode_operations ---------------------------
prototypes:
- int (*create) (struct inode *,struct dentry *,umode_t, struct nameidata *);
- struct dentry * (*lookup) (struct inode *,struct dentry *, struct nameid
-ata *);
+ int (*create) (struct inode *,struct dentry *,umode_t, bool);
+ struct dentry * (*lookup) (struct inode *,struct dentry *, unsigned int);
int (*link) (struct dentry *,struct inode *,struct dentry *);
int (*unlink) (struct inode *,struct dentry *);
int (*symlink) (struct inode *,struct dentry *,const char *);
@@ -62,6 +61,9 @@ ata *);
int (*removexattr) (struct dentry *, const char *);
int (*fiemap)(struct inode *, struct fiemap_extent_info *, u64 start, u64 len);
void (*update_time)(struct inode *, struct timespec *, int);
+ int (*atomic_open)(struct inode *, struct dentry *,
+ struct file *, unsigned open_flag,
+ umode_t create_mode, int *opened);
locking rules:
all may block
@@ -78,7 +80,6 @@ rename: yes (all) (see below)
readlink: no
follow_link: no
put_link: no
-truncate: yes (see below)
setattr: yes
permission: no (may not block if called in rcu-walk mode)
get_acl: no
@@ -89,15 +90,11 @@ listxattr: no
removexattr: yes
fiemap: no
update_time: no
+atomic_open: yes
Additionally, ->rmdir(), ->unlink() and ->rename() have ->i_mutex on
victim.
cross-directory ->rename() has (per-superblock) ->s_vfs_rename_sem.
- ->truncate() is never called directly - it's a callback, not a
-method. It's called by vmtruncate() - deprecated library function used by
-->setattr(). Locking information above applies to that call (i.e. is
-inherited from ->setattr() - vmtruncate() is used when ATTR_SIZE had been
-passed).
See Documentation/filesystems/directory-locking for more detailed discussion
of the locking scheme for directory operations.
@@ -111,7 +108,6 @@ prototypes:
int (*drop_inode) (struct inode *);
void (*evict_inode) (struct inode *);
void (*put_super) (struct super_block *);
- void (*write_super) (struct super_block *);
int (*sync_fs)(struct super_block *sb, int wait);
int (*freeze_fs) (struct super_block *);
int (*unfreeze_fs) (struct super_block *);
@@ -133,10 +129,9 @@ write_inode:
drop_inode: !!!inode->i_lock!!!
evict_inode:
put_super: write
-write_super: read
sync_fs: read
-freeze_fs: read
-unfreeze_fs: read
+freeze_fs: write
+unfreeze_fs: write
statfs: maybe(read) (see below)
remount_fs: write
umount_begin: no
@@ -203,6 +198,8 @@ prototypes:
int (*launder_page)(struct page *);
int (*is_partially_uptodate)(struct page *, read_descriptor_t *, unsigned long);
int (*error_remove_page)(struct address_space *, struct page *);
+ int (*swap_activate)(struct file *);
+ int (*swap_deactivate)(struct file *);
locking rules:
All except set_page_dirty and freepage may block
@@ -226,6 +223,8 @@ migratepage: yes (both)
launder_page: yes
is_partially_uptodate: yes
error_remove_page: yes
+swap_activate: no
+swap_deactivate: no
->write_begin(), ->write_end(), ->sync_page() and ->readpage()
may be called from the request handler (/dev/loop).
@@ -327,6 +326,15 @@ cleaned, or an error value if not. Note that in order to prevent the page
getting mapped back in and redirtied, it needs to be kept locked
across the entire operation.
+ ->swap_activate will be called with a non-zero argument on
+files backing (non block device backed) swapfiles. A return value
+of zero indicates success, in which case this file can be used for
+backing swapspace. The swapspace operations will be proxied to the
+address space operations.
+
+ ->swap_deactivate() will be called in the sys_swapoff()
+path after ->swap_activate() returned success.
+
----------------------- file_lock_operations ------------------------------
prototypes:
void (*fl_copy_lock)(struct file_lock *, struct file_lock *);
@@ -343,7 +351,6 @@ prototypes:
int (*lm_compare_owner)(struct file_lock *, struct file_lock *);
void (*lm_notify)(struct file_lock *); /* unblock callback */
int (*lm_grant)(struct file_lock *, struct file_lock *, int);
- void (*lm_release_private)(struct file_lock *);
void (*lm_break)(struct file_lock *); /* break_lease callback */
int (*lm_change)(struct file_lock **, int);
@@ -352,7 +359,6 @@ locking rules:
lm_compare_owner: yes no
lm_notify: yes no
lm_grant: no no
-lm_release_private: maybe no
lm_break: yes no
lm_change yes no