summaryrefslogtreecommitdiff
path: root/Documentation/filesystems
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/filesystems')
-rw-r--r--Documentation/filesystems/Locking9
-rw-r--r--Documentation/filesystems/ntfs.txt5
-rw-r--r--Documentation/filesystems/porting17
-rw-r--r--Documentation/filesystems/proc.txt7
-rw-r--r--Documentation/filesystems/vfs.txt47
5 files changed, 75 insertions, 10 deletions
diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking
index 977d8919cc69..4471a416c274 100644
--- a/Documentation/filesystems/Locking
+++ b/Documentation/filesystems/Locking
@@ -19,6 +19,8 @@ prototypes:
void (*d_release)(struct dentry *);
void (*d_iput)(struct dentry *, struct inode *);
char *(*d_dname)((struct dentry *dentry, char *buffer, int buflen);
+ struct vfsmount *(*d_automount)(struct path *path);
+ int (*d_manage)(struct dentry *, bool);
locking rules:
rename_lock ->d_lock may block rcu-walk
@@ -29,6 +31,8 @@ d_delete: no yes no no
d_release: no no yes no
d_iput: no no yes no
d_dname: no no no no
+d_automount: no no yes no
+d_manage: no no yes (ref-walk) maybe
--------------------------- inode_operations ---------------------------
prototypes:
@@ -56,7 +60,6 @@ ata *);
ssize_t (*listxattr) (struct dentry *, char *, size_t);
int (*removexattr) (struct dentry *, const char *);
void (*truncate_range)(struct inode *, loff_t, loff_t);
- long (*fallocate)(struct inode *inode, int mode, loff_t offset, loff_t len);
int (*fiemap)(struct inode *, struct fiemap_extent_info *, u64 start, u64 len);
locking rules:
@@ -84,7 +87,6 @@ getxattr: no
listxattr: no
removexattr: yes
truncate_range: yes
-fallocate: no
fiemap: no
Additionally, ->rmdir(), ->unlink() and ->rename() have ->i_mutex on
victim.
@@ -343,7 +345,6 @@ prototypes:
int (*fl_grant)(struct file_lock *, struct file_lock *, int);
void (*fl_release_private)(struct file_lock *);
void (*fl_break)(struct file_lock *); /* break_lease callback */
- int (*fl_mylease)(struct file_lock *, struct file_lock *);
int (*fl_change)(struct file_lock **, int);
locking rules:
@@ -353,7 +354,6 @@ fl_notify: yes no
fl_grant: no no
fl_release_private: maybe no
fl_break: yes no
-fl_mylease: yes no
fl_change yes no
--------------------------- buffer_head -----------------------------------
@@ -435,6 +435,7 @@ prototypes:
ssize_t (*splice_read)(struct file *, loff_t *, struct pipe_inode_info *,
size_t, unsigned int);
int (*setlease)(struct file *, long, struct file_lock **);
+ long (*fallocate)(struct file *, int, loff_t, loff_t);
};
locking rules:
diff --git a/Documentation/filesystems/ntfs.txt b/Documentation/filesystems/ntfs.txt
index ac2a261c5f7d..933bc66ccff1 100644
--- a/Documentation/filesystems/ntfs.txt
+++ b/Documentation/filesystems/ntfs.txt
@@ -457,6 +457,11 @@ ChangeLog
Note, a technical ChangeLog aimed at kernel hackers is in fs/ntfs/ChangeLog.
+2.1.30:
+ - Fix writev() (it kept writing the first segment over and over again
+ instead of moving onto subsequent segments).
+ - Fix crash in ntfs_mft_record_alloc() when mapping the new extent mft
+ record failed.
2.1.29:
- Fix a deadlock when mounting read-write.
2.1.28:
diff --git a/Documentation/filesystems/porting b/Documentation/filesystems/porting
index 07a32b42cf9c..dfbcd1b00b0a 100644
--- a/Documentation/filesystems/porting
+++ b/Documentation/filesystems/porting
@@ -365,8 +365,8 @@ must be done in the RCU callback.
[recommended]
vfs now tries to do path walking in "rcu-walk mode", which avoids
atomic operations and scalability hazards on dentries and inodes (see
-Documentation/filesystems/path-walk.txt). d_hash and d_compare changes (above)
-are examples of the changes required to support this. For more complex
+Documentation/filesystems/path-lookup.txt). d_hash and d_compare changes
+(above) are examples of the changes required to support this. For more complex
filesystem callbacks, the vfs drops out of rcu-walk mode before the fs call, so
no changes are required to the filesystem. However, this is costly and loses
the benefits of rcu-walk mode. We will begin to add filesystem callbacks that
@@ -383,5 +383,14 @@ Documentation/filesystems/vfs.txt for more details.
permission and check_acl are inode permission checks that are called
on many or all directory inodes on the way down a path walk (to check for
-exec permission). These must now be rcu-walk aware (flags & IPERM_RCU). See
-Documentation/filesystems/vfs.txt for more details.
+exec permission). These must now be rcu-walk aware (flags & IPERM_FLAG_RCU).
+See Documentation/filesystems/vfs.txt for more details.
+
+--
+[mandatory]
+ In ->fallocate() you must check the mode option passed in. If your
+filesystem does not support hole punching (deallocating space in the middle of a
+file) you must return -EOPNOTSUPP if FALLOC_FL_PUNCH_HOLE is set in mode.
+Currently you can only have FALLOC_FL_PUNCH_HOLE with FALLOC_FL_KEEP_SIZE set,
+so the i_size should not change when hole punching, even when puching the end of
+a file off.
diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt
index 9471225212c4..23cae6548d3a 100644
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -375,6 +375,7 @@ Anonymous: 0 kB
Swap: 0 kB
KernelPageSize: 4 kB
MMUPageSize: 4 kB
+Locked: 374 kB
The first of these lines shows the same information as is displayed for the
mapping in /proc/PID/maps. The remaining lines show the size of the mapping
@@ -670,6 +671,8 @@ varies by architecture and compile options. The following is from a
> cat /proc/meminfo
+The "Locked" indicates whether the mapping is locked in memory or not.
+
MemTotal: 16344972 kB
MemFree: 13634064 kB
@@ -1320,6 +1323,10 @@ scaled linearly with /proc/<pid>/oom_score_adj.
Writing to /proc/<pid>/oom_score_adj or /proc/<pid>/oom_adj will change the
other with its scaled value.
+The value of /proc/<pid>/oom_score_adj may be reduced no lower than the last
+value set by a CAP_SYS_RESOURCE process. To reduce the value any lower
+requires CAP_SYS_RESOURCE.
+
NOTICE: /proc/<pid>/oom_adj is deprecated and will be removed, please see
Documentation/feature-removal-schedule.txt.
diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt
index fbb324e2bd43..94cf97b901d7 100644
--- a/Documentation/filesystems/vfs.txt
+++ b/Documentation/filesystems/vfs.txt
@@ -415,8 +415,8 @@ otherwise noted.
permission: called by the VFS to check for access rights on a POSIX-like
filesystem.
- May be called in rcu-walk mode (flags & IPERM_RCU). If in rcu-walk
- mode, the filesystem must check the permission without blocking or
+ May be called in rcu-walk mode (flags & IPERM_FLAG_RCU). If in rcu-walk
+ mode, the filesystem must check the permission without blocking or
storing to the inode.
If a situation is encountered that rcu-walk cannot handle, return
@@ -864,6 +864,8 @@ struct dentry_operations {
void (*d_release)(struct dentry *);
void (*d_iput)(struct dentry *, struct inode *);
char *(*d_dname)(struct dentry *, char *, int);
+ struct vfsmount *(*d_automount)(struct path *);
+ int (*d_manage)(struct dentry *, bool, bool);
};
d_revalidate: called when the VFS needs to revalidate a dentry. This
@@ -930,6 +932,47 @@ struct dentry_operations {
at the end of the buffer, and returns a pointer to the first char.
dynamic_dname() helper function is provided to take care of this.
+ d_automount: called when an automount dentry is to be traversed (optional).
+ This should create a new VFS mount record and return the record to the
+ caller. The caller is supplied with a path parameter giving the
+ automount directory to describe the automount target and the parent
+ VFS mount record to provide inheritable mount parameters. NULL should
+ be returned if someone else managed to make the automount first. If
+ the vfsmount creation failed, then an error code should be returned.
+ If -EISDIR is returned, then the directory will be treated as an
+ ordinary directory and returned to pathwalk to continue walking.
+
+ If a vfsmount is returned, the caller will attempt to mount it on the
+ mountpoint and will remove the vfsmount from its expiration list in
+ the case of failure. The vfsmount should be returned with 2 refs on
+ it to prevent automatic expiration - the caller will clean up the
+ additional ref.
+
+ This function is only used if DCACHE_NEED_AUTOMOUNT is set on the
+ dentry. This is set by __d_instantiate() if S_AUTOMOUNT is set on the
+ inode being added.
+
+ d_manage: called to allow the filesystem to manage the transition from a
+ dentry (optional). This allows autofs, for example, to hold up clients
+ waiting to explore behind a 'mountpoint' whilst letting the daemon go
+ past and construct the subtree there. 0 should be returned to let the
+ calling process continue. -EISDIR can be returned to tell pathwalk to
+ use this directory as an ordinary directory and to ignore anything
+ mounted on it and not to check the automount flag. Any other error
+ code will abort pathwalk completely.
+
+ If the 'mounting_here' parameter is true, then namespace_sem is being
+ held by the caller and the function should not initiate any mounts or
+ unmounts that it will then wait for.
+
+ If the 'rcu_walk' parameter is true, then the caller is doing a
+ pathwalk in RCU-walk mode. Sleeping is not permitted in this mode,
+ and the caller can be asked to leave it and call again by returing
+ -ECHILD.
+
+ This function is only used if DCACHE_MANAGE_TRANSIT is set on the
+ dentry being transited from.
+
Example :
static char *pipefs_dname(struct dentry *dent, char *buffer, int buflen)