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authorLinus Torvalds <torvalds@linux-foundation.org>2014-04-08 01:38:06 +0200
committerLinus Torvalds <torvalds@linux-foundation.org>2014-04-08 01:38:06 +0200
commit26c12d93348f0bda0756aff83f4867d9ae58a5a6 (patch)
tree65221f6837c66a9260c5c973e5fb908b10e0d504 /Documentation/filesystems
parentMerge branch 'for-3.15-fixes' of git://git.kernel.org/pub/scm/linux/kernel/gi... (diff)
parentMAINTAINERS: update Intel C600 SAS driver maintainers (diff)
downloadlinux-26c12d93348f0bda0756aff83f4867d9ae58a5a6.tar.xz
linux-26c12d93348f0bda0756aff83f4867d9ae58a5a6.zip
Merge branch 'akpm' (incoming from Andrew)
Merge second patch-bomb from Andrew Morton: - the rest of MM - zram updates - zswap updates - exit - procfs - exec - wait - crash dump - lib/idr - rapidio - adfs, affs, bfs, ufs - cris - Kconfig things - initramfs - small amount of IPC material - percpu enhancements - early ioremap support - various other misc things * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (156 commits) MAINTAINERS: update Intel C600 SAS driver maintainers fs/ufs: remove unused ufs_super_block_third pointer fs/ufs: remove unused ufs_super_block_second pointer fs/ufs: remove unused ufs_super_block_first pointer fs/ufs/super.c: add __init to init_inodecache() doc/kernel-parameters.txt: add early_ioremap_debug arm64: add early_ioremap support arm64: initialize pgprot info earlier in boot x86: use generic early_ioremap mm: create generic early_ioremap() support x86/mm: sparse warning fix for early_memremap lglock: map to spinlock when !CONFIG_SMP percpu: add preemption checks to __this_cpu ops vmstat: use raw_cpu_ops to avoid false positives on preemption checks slub: use raw_cpu_inc for incrementing statistics net: replace __this_cpu_inc in route.c with raw_cpu_inc modules: use raw_cpu_write for initialization of per cpu refcount. mm: use raw_cpu ops for determining current NUMA node percpu: add raw_cpu_ops slub: fix leak of 'name' in sysfs_slab_add ...
Diffstat (limited to 'Documentation/filesystems')
-rw-r--r--Documentation/filesystems/Locking10
-rw-r--r--Documentation/filesystems/affs.txt9
-rw-r--r--Documentation/filesystems/proc.txt17
3 files changed, 28 insertions, 8 deletions
diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking
index f424e0e5b46b..efca5c1bbb10 100644
--- a/Documentation/filesystems/Locking
+++ b/Documentation/filesystems/Locking
@@ -529,6 +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
@@ -540,6 +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/proc.txt b/Documentation/filesystems/proc.txt
index f00bee144add..8b9cd8eb3f91 100644
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -1648,18 +1648,21 @@ 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 +1671,7 @@ 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 +1680,7 @@ 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 +1690,7 @@ 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 +1724,7 @@ 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