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-rw-r--r--Documentation/filesystems/Locking18
-rw-r--r--Documentation/filesystems/affs.txt9
-rw-r--r--Documentation/filesystems/autofs4-mount-control.txt2
-rw-r--r--Documentation/filesystems/f2fs.txt29
-rw-r--r--Documentation/filesystems/hfsplus.txt2
-rw-r--r--Documentation/filesystems/nilfs2.txt12
-rw-r--r--Documentation/filesystems/ntfs.txt2
-rw-r--r--Documentation/filesystems/porting6
-rw-r--r--Documentation/filesystems/proc.txt29
-rw-r--r--Documentation/filesystems/seq_file.txt9
-rw-r--r--Documentation/filesystems/sharedsubtree.txt2
-rw-r--r--Documentation/filesystems/vfat.txt5
-rw-r--r--Documentation/filesystems/vfs.txt18
13 files changed, 111 insertions, 32 deletions
diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking
index 5b0c083d7c0e..eba790134253 100644
--- a/Documentation/filesystems/Locking
+++ b/Documentation/filesystems/Locking
@@ -47,6 +47,8 @@ prototypes:
int (*mknod) (struct inode *,struct dentry *,umode_t,dev_t);
int (*rename) (struct inode *, struct dentry *,
struct inode *, struct dentry *);
+ int (*rename2) (struct inode *, struct dentry *,
+ struct inode *, struct dentry *, unsigned int);
int (*readlink) (struct dentry *, char __user *,int);
void * (*follow_link) (struct dentry *, struct nameidata *);
void (*put_link) (struct dentry *, struct nameidata *, void *);
@@ -78,6 +80,7 @@ mkdir: yes
unlink: yes (both)
rmdir: yes (both) (see below)
rename: yes (all) (see below)
+rename2: yes (all) (see below)
readlink: no
follow_link: no
put_link: no
@@ -96,7 +99,8 @@ tmpfile: no
Additionally, ->rmdir(), ->unlink() and ->rename() have ->i_mutex on
victim.
- cross-directory ->rename() has (per-superblock) ->s_vfs_rename_sem.
+ cross-directory ->rename() and rename2() has (per-superblock)
+->s_vfs_rename_sem.
See Documentation/filesystems/directory-locking for more detailed discussion
of the locking scheme for directory operations.
@@ -198,7 +202,7 @@ prototypes:
unsigned long *);
int (*migratepage)(struct address_space *, struct page *, struct page *);
int (*launder_page)(struct page *);
- int (*is_partially_uptodate)(struct page *, read_descriptor_t *, unsigned long);
+ int (*is_partially_uptodate)(struct page *, unsigned long, unsigned long);
int (*error_remove_page)(struct address_space *, struct page *);
int (*swap_activate)(struct file *);
int (*swap_deactivate)(struct file *);
@@ -525,6 +529,7 @@ locking rules:
open: yes
close: yes
fault: yes can return with page locked
+map_pages: yes
page_mkwrite: yes can return with page locked
access: yes
@@ -536,6 +541,15 @@ the page, then ensure it is not already truncated (the page lock will block
subsequent truncate), and then return with VM_FAULT_LOCKED, and the page
locked. The VM will unlock the page.
+ ->map_pages() is called when VM asks to map easy accessible pages.
+Filesystem should find and map pages associated with offsets from "pgoff"
+till "max_pgoff". ->map_pages() is called with page table locked and must
+not block. If it's not possible to reach a page without blocking,
+filesystem should skip it. Filesystem should use do_set_pte() to setup
+page table entry. Pointer to entry associated with offset "pgoff" is
+passed in "pte" field in vm_fault structure. Pointers to entries for other
+offsets should be calculated relative to "pte".
+
->page_mkwrite() is called when a previously read-only pte is
about to become writeable. The filesystem again must ensure that there are
no truncate/invalidate races, and then return with the page locked. If
diff --git a/Documentation/filesystems/affs.txt b/Documentation/filesystems/affs.txt
index 81ac488e3758..71b63c2b9841 100644
--- a/Documentation/filesystems/affs.txt
+++ b/Documentation/filesystems/affs.txt
@@ -49,6 +49,10 @@ mode=mode Sets the mode flags to the given (octal) value, regardless
This is useful since most of the plain AmigaOS files
will map to 600.
+nofilenametruncate
+ The file system will return an error when filename exceeds
+ standard maximum filename length (30 characters).
+
reserved=num Sets the number of reserved blocks at the start of the
partition to num. You should never need this option.
Default is 2.
@@ -181,9 +185,8 @@ tested, though several hundred MB have been read and written using
this fs. For a most up-to-date list of bugs please consult
fs/affs/Changes.
-Filenames are truncated to 30 characters without warning (this
-can be changed by setting the compile-time option AFFS_NO_TRUNCATE
-in include/linux/amigaffs.h).
+By default, filenames are truncated to 30 characters without warning.
+'nofilenametruncate' mount option can change that behavior.
Case is ignored by the affs in filename matching, but Linux shells
do care about the case. Example (with /wb being an affs mounted fs):
diff --git a/Documentation/filesystems/autofs4-mount-control.txt b/Documentation/filesystems/autofs4-mount-control.txt
index 4c95935cbcf4..aff22113a986 100644
--- a/Documentation/filesystems/autofs4-mount-control.txt
+++ b/Documentation/filesystems/autofs4-mount-control.txt
@@ -255,7 +255,7 @@ AUTOFS_DEV_IOCTL_OPENMOUNT and AUTOFS_DEV_IOCTL_CLOSEMOUNT
Obtain and release a file descriptor for an autofs managed mount point
path. The open call requires an initialized struct autofs_dev_ioctl with
-the the path field set and the size field adjusted appropriately as well
+the path field set and the size field adjusted appropriately as well
as the arg1 field set to the device number of the autofs mount. The
device number can be obtained from the mount options shown in
/proc/mounts. The close call requires an initialized struct
diff --git a/Documentation/filesystems/f2fs.txt b/Documentation/filesystems/f2fs.txt
index b8d284975f0f..51afba17bbae 100644
--- a/Documentation/filesystems/f2fs.txt
+++ b/Documentation/filesystems/f2fs.txt
@@ -122,6 +122,10 @@ disable_ext_identify Disable the extension list configured by mkfs, so f2fs
inline_xattr Enable the inline xattrs feature.
inline_data Enable the inline data feature: New created small(<~3.4k)
files can be written into inode block.
+flush_merge Merge concurrent cache_flush commands as much as possible
+ to eliminate redundant command issues. If the underlying
+ device handles the cache_flush command relatively slowly,
+ recommend to enable this option.
================================================================================
DEBUGFS ENTRIES
@@ -169,9 +173,11 @@ Files in /sys/fs/f2fs/<devname>
reclaim_segments This parameter controls the number of prefree
segments to be reclaimed. If the number of prefree
- segments is larger than this number, f2fs tries to
- conduct checkpoint to reclaim the prefree segments
- to free segments. By default, 100 segments, 200MB.
+ segments is larger than the number of segments
+ in the proportion to the percentage over total
+ volume size, f2fs tries to conduct checkpoint to
+ reclaim the prefree segments to free segments.
+ By default, 5% over total # of segments.
max_small_discards This parameter controls the number of discard
commands that consist small blocks less than 2MB.
@@ -195,6 +201,17 @@ Files in /sys/fs/f2fs/<devname>
cleaning operations. The default value is 4096
which covers 8GB block address range.
+ dir_level This parameter controls the directory level to
+ support large directory. If a directory has a
+ number of files, it can reduce the file lookup
+ latency by increasing this dir_level value.
+ Otherwise, it needs to decrease this value to
+ reduce the space overhead. The default value is 0.
+
+ ram_thresh This parameter controls the memory footprint used
+ by free nids and cached nat entries. By default,
+ 10 is set, which indicates 10 MB / 1 GB RAM.
+
================================================================================
USAGE
================================================================================
@@ -444,9 +461,11 @@ The number of blocks and buckets are determined by,
# of blocks in level #n = |
`- 4, Otherwise
- ,- 2^n, if n < MAX_DIR_HASH_DEPTH / 2,
+ ,- 2^(n + dir_level),
+ | if n + dir_level < MAX_DIR_HASH_DEPTH / 2,
# of buckets in level #n = |
- `- 2^((MAX_DIR_HASH_DEPTH / 2) - 1), Otherwise
+ `- 2^((MAX_DIR_HASH_DEPTH / 2) - 1),
+ Otherwise
When F2FS finds a file name in a directory, at first a hash value of the file
name is calculated. Then, F2FS scans the hash table in level #0 to find the
diff --git a/Documentation/filesystems/hfsplus.txt b/Documentation/filesystems/hfsplus.txt
index af1628a1061c..59f7569fc9ed 100644
--- a/Documentation/filesystems/hfsplus.txt
+++ b/Documentation/filesystems/hfsplus.txt
@@ -56,4 +56,4 @@ References
kernel source: <file:fs/hfsplus>
-Apple Technote 1150 http://developer.apple.com/technotes/tn/tn1150.html
+Apple Technote 1150 https://developer.apple.com/legacy/library/technotes/tn/tn1150.html
diff --git a/Documentation/filesystems/nilfs2.txt b/Documentation/filesystems/nilfs2.txt
index 06887d46ccf2..41c3d332acc9 100644
--- a/Documentation/filesystems/nilfs2.txt
+++ b/Documentation/filesystems/nilfs2.txt
@@ -25,9 +25,8 @@ available from the following download page. At least "mkfs.nilfs2",
cleaner or garbage collector) are required. Details on the tools are
described in the man pages included in the package.
-Project web page: http://www.nilfs.org/en/
-Download page: http://www.nilfs.org/en/download.html
-Git tree web page: http://www.nilfs.org/git/
+Project web page: http://nilfs.sourceforge.net/
+Download page: http://nilfs.sourceforge.net/en/download.html
List info: http://vger.kernel.org/vger-lists.html#linux-nilfs
Caveats
@@ -111,6 +110,13 @@ Table of NILFS2 specific ioctls
nilfs_resize utilities and by nilfs_cleanerd
daemon.
+ NILFS_IOCTL_SET_SUINFO Modify segment usage info of requested
+ segments. This ioctl is used by
+ nilfs_cleanerd daemon to skip unnecessary
+ cleaning operation of segments and reduce
+ performance penalty or wear of flash device
+ due to redundant move of in-use blocks.
+
NILFS_IOCTL_GET_SUSTAT Return segment usage statistics. This ioctl
is used in lssu, nilfs_resize utilities and
by nilfs_cleanerd daemon.
diff --git a/Documentation/filesystems/ntfs.txt b/Documentation/filesystems/ntfs.txt
index 791af8dac065..61947facfc07 100644
--- a/Documentation/filesystems/ntfs.txt
+++ b/Documentation/filesystems/ntfs.txt
@@ -455,8 +455,6 @@ not have this problem with odd numbers of sectors.
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).
diff --git a/Documentation/filesystems/porting b/Documentation/filesystems/porting
index fe2b7ae6f962..0f3a1390bf00 100644
--- a/Documentation/filesystems/porting
+++ b/Documentation/filesystems/porting
@@ -295,9 +295,9 @@ in the beginning of ->setattr unconditionally.
->clear_inode() and ->delete_inode() are gone; ->evict_inode() should
be used instead. It gets called whenever the inode is evicted, whether it has
remaining links or not. Caller does *not* evict the pagecache or inode-associated
-metadata buffers; getting rid of those is responsibility of method, as it had
-been for ->delete_inode(). Caller makes sure async writeback cannot be running
-for the inode while (or after) ->evict_inode() is called.
+metadata buffers; the method has to use truncate_inode_pages_final() to get rid
+of those. Caller makes sure async writeback cannot be running for the inode while
+(or after) ->evict_inode() is called.
->drop_inode() returns int now; it's called on final iput() with
inode->i_lock held and it returns true if filesystems wants the inode to be
diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt
index f00bee144add..ddc531a74d04 100644
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -234,7 +234,7 @@ Table 1-2: Contents of the status files (as of 2.6.30-rc7)
ShdPnd bitmap of shared pending signals for the process
SigBlk bitmap of blocked signals
SigIgn bitmap of ignored signals
- SigCgt bitmap of catched signals
+ SigCgt bitmap of caught signals
CapInh bitmap of inheritable capabilities
CapPrm bitmap of permitted capabilities
CapEff bitmap of effective capabilities
@@ -300,7 +300,7 @@ Table 1-4: Contents of the stat files (as of 2.6.30-rc7)
pending bitmap of pending signals
blocked bitmap of blocked signals
sigign bitmap of ignored signals
- sigcatch bitmap of catched signals
+ sigcatch bitmap of caught signals
wchan address where process went to sleep
0 (place holder)
0 (place holder)
@@ -854,7 +854,8 @@ WritebackTmp: Memory used by FUSE for temporary writeback buffers
if strict overcommit accounting is enabled (mode 2 in
'vm.overcommit_memory').
The CommitLimit is calculated with the following formula:
- CommitLimit = ('vm.overcommit_ratio' * Physical RAM) + Swap
+ CommitLimit = ([total RAM pages] - [total huge TLB pages]) *
+ overcommit_ratio / 100 + [total swap pages]
For example, on a system with 1G of physical RAM and 7G
of swap with a `vm.overcommit_ratio` of 30 it would
yield a CommitLimit of 7.3G.
@@ -1245,8 +1246,9 @@ second). The meanings of the columns are as follows, from left to right:
The "intr" line gives counts of interrupts serviced since boot time, for each
of the possible system interrupts. The first column is the total of all
-interrupts serviced; each subsequent column is the total for that particular
-interrupt.
+interrupts serviced including unnumbered architecture specific interrupts;
+each subsequent column is the total for that particular numbered interrupt.
+Unnumbered interrupts are not shown, only summed into the total.
The "ctxt" line gives the total number of context switches across all CPUs.
@@ -1648,18 +1650,21 @@ pids, so one need to either stop or freeze processes being inspected
if precise results are needed.
-3.7 /proc/<pid>/fdinfo/<fd> - Information about opened file
+3.8 /proc/<pid>/fdinfo/<fd> - Information about opened file
---------------------------------------------------------------
This file provides information associated with an opened file. The regular
-files have at least two fields -- 'pos' and 'flags'. The 'pos' represents
-the current offset of the opened file in decimal form [see lseek(2) for
-details] and 'flags' denotes the octal O_xxx mask the file has been
-created with [see open(2) for details].
+files have at least three fields -- 'pos', 'flags' and mnt_id. The 'pos'
+represents the current offset of the opened file in decimal form [see lseek(2)
+for details], 'flags' denotes the octal O_xxx mask the file has been
+created with [see open(2) for details] and 'mnt_id' represents mount ID of
+the file system containing the opened file [see 3.5 /proc/<pid>/mountinfo
+for details].
A typical output is
pos: 0
flags: 0100002
+ mnt_id: 19
The files such as eventfd, fsnotify, signalfd, epoll among the regular pos/flags
pair provide additional information particular to the objects they represent.
@@ -1668,6 +1673,7 @@ pair provide additional information particular to the objects they represent.
~~~~~~~~~~~~~
pos: 0
flags: 04002
+ mnt_id: 9
eventfd-count: 5a
where 'eventfd-count' is hex value of a counter.
@@ -1676,6 +1682,7 @@ pair provide additional information particular to the objects they represent.
~~~~~~~~~~~~~~
pos: 0
flags: 04002
+ mnt_id: 9
sigmask: 0000000000000200
where 'sigmask' is hex value of the signal mask associated
@@ -1685,6 +1692,7 @@ pair provide additional information particular to the objects they represent.
~~~~~~~~~~~
pos: 0
flags: 02
+ mnt_id: 9
tfd: 5 events: 1d data: ffffffffffffffff
where 'tfd' is a target file descriptor number in decimal form,
@@ -1718,6 +1726,7 @@ pair provide additional information particular to the objects they represent.
pos: 0
flags: 02
+ mnt_id: 9
fanotify flags:10 event-flags:0
fanotify mnt_id:12 mflags:40 mask:38 ignored_mask:40000003
fanotify ino:4f969 sdev:800013 mflags:0 mask:3b ignored_mask:40000000 fhandle-bytes:8 fhandle-type:1 f_handle:69f90400c275b5b4
diff --git a/Documentation/filesystems/seq_file.txt b/Documentation/filesystems/seq_file.txt
index a1e2e0dda907..1fe0ccb1af55 100644
--- a/Documentation/filesystems/seq_file.txt
+++ b/Documentation/filesystems/seq_file.txt
@@ -54,6 +54,15 @@ how the mechanism works without getting lost in other details. (Those
wanting to see the full source for this module can find it at
http://lwn.net/Articles/22359/).
+Deprecated create_proc_entry
+
+Note that the above article uses create_proc_entry which was removed in
+kernel 3.10. Current versions require the following update
+
+- entry = create_proc_entry("sequence", 0, NULL);
+- if (entry)
+- entry->proc_fops = &ct_file_ops;
++ entry = proc_create("sequence", 0, NULL, &ct_file_ops);
The iterator interface
diff --git a/Documentation/filesystems/sharedsubtree.txt b/Documentation/filesystems/sharedsubtree.txt
index 4ede421c9687..32a173dd3158 100644
--- a/Documentation/filesystems/sharedsubtree.txt
+++ b/Documentation/filesystems/sharedsubtree.txt
@@ -727,7 +727,7 @@ replicas continue to be exactly same.
mkdir -p /tmp/m3
mount --rbind /root /tmp/m3
- I wont' draw the tree..but it has 24 vfsmounts
+ I won't draw the tree..but it has 24 vfsmounts
at step i the number of vfsmounts is V[i] = i*V[i-1].
diff --git a/Documentation/filesystems/vfat.txt b/Documentation/filesystems/vfat.txt
index 4a93e98b290a..ce1126aceed8 100644
--- a/Documentation/filesystems/vfat.txt
+++ b/Documentation/filesystems/vfat.txt
@@ -172,6 +172,11 @@ nfs=stale_rw|nostale_ro
To maintain backward compatibility, '-o nfs' is also accepted,
defaulting to stale_rw
+dos1xfloppy -- If set, use a fallback default BIOS Parameter Block
+ configuration, determined by backing device size. These static
+ parameters match defaults assumed by DOS 1.x for 160 kiB,
+ 180 kiB, 320 kiB, and 360 kiB floppies and floppy images.
+
<bool>: 0,1,yes,no,true,false
diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt
index c53784c119c8..617f6d70c077 100644
--- a/Documentation/filesystems/vfs.txt
+++ b/Documentation/filesystems/vfs.txt
@@ -347,6 +347,8 @@ struct inode_operations {
int (*mknod) (struct inode *,struct dentry *,umode_t,dev_t);
int (*rename) (struct inode *, struct dentry *,
struct inode *, struct dentry *);
+ int (*rename2) (struct inode *, struct dentry *,
+ struct inode *, struct dentry *, unsigned int);
int (*readlink) (struct dentry *, char __user *,int);
void * (*follow_link) (struct dentry *, struct nameidata *);
void (*put_link) (struct dentry *, struct nameidata *, void *);
@@ -414,6 +416,20 @@ otherwise noted.
rename: called by the rename(2) system call to rename the object to
have the parent and name given by the second inode and dentry.
+ rename2: this has an additional flags argument compared to rename.
+ If no flags are supported by the filesystem then this method
+ need not be implemented. If some flags are supported then the
+ filesystem must return -EINVAL for any unsupported or unknown
+ flags. Currently the following flags are implemented:
+ (1) RENAME_NOREPLACE: this flag indicates that if the target
+ of the rename exists the rename should fail with -EEXIST
+ instead of replacing the target. The VFS already checks for
+ existence, so for local filesystems the RENAME_NOREPLACE
+ implementation is equivalent to plain rename.
+ (2) RENAME_EXCHANGE: exchange source and target. Both must
+ exist; this is checked by the VFS. Unlike plain rename,
+ source and target may be of different type.
+
readlink: called by the readlink(2) system call. Only required if
you want to support reading symbolic links
@@ -580,7 +596,7 @@ struct address_space_operations {
/* migrate the contents of a page to the specified target */
int (*migratepage) (struct page *, struct page *);
int (*launder_page) (struct page *);
- int (*is_partially_uptodate) (struct page *, read_descriptor_t *,
+ int (*is_partially_uptodate) (struct page *, unsigned long,
unsigned long);
void (*is_dirty_writeback) (struct page *, bool *, bool *);
int (*error_remove_page) (struct mapping *mapping, struct page *page);