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-rw-r--r--Documentation/filesystems/autofs4-mount-control.txt2
-rw-r--r--Documentation/filesystems/caching/netfs-api.txt2
-rw-r--r--Documentation/filesystems/debugfs.txt158
-rw-r--r--Documentation/filesystems/ext4.txt6
-rw-r--r--Documentation/filesystems/fiemap.txt2
-rw-r--r--Documentation/filesystems/gfs2-glocks.txt2
-rw-r--r--Documentation/filesystems/gfs2.txt19
-rw-r--r--Documentation/filesystems/nfs-rdma.txt2
-rw-r--r--Documentation/filesystems/proc.txt4
-rw-r--r--Documentation/filesystems/sysfs-pci.txt2
-rw-r--r--Documentation/filesystems/vfat.txt8
11 files changed, 184 insertions, 23 deletions
diff --git a/Documentation/filesystems/autofs4-mount-control.txt b/Documentation/filesystems/autofs4-mount-control.txt
index c6341745df37..8f78ded4b648 100644
--- a/Documentation/filesystems/autofs4-mount-control.txt
+++ b/Documentation/filesystems/autofs4-mount-control.txt
@@ -369,7 +369,7 @@ The call requires an initialized struct autofs_dev_ioctl. There are two
369possible variations. Both use the path field set to the path of the mount 369possible variations. Both use the path field set to the path of the mount
370point to check and the size field adjusted appropriately. One uses the 370point to check and the size field adjusted appropriately. One uses the
371ioctlfd field to identify a specific mount point to check while the other 371ioctlfd field to identify a specific mount point to check while the other
372variation uses the path and optionaly arg1 set to an autofs mount type. 372variation uses the path and optionally arg1 set to an autofs mount type.
373The call returns 1 if this is a mount point and sets arg1 to the device 373The call returns 1 if this is a mount point and sets arg1 to the device
374number of the mount and field arg2 to the relevant super block magic 374number of the mount and field arg2 to the relevant super block magic
375number (described below) or 0 if it isn't a mountpoint. In both cases 375number (described below) or 0 if it isn't a mountpoint. In both cases
diff --git a/Documentation/filesystems/caching/netfs-api.txt b/Documentation/filesystems/caching/netfs-api.txt
index 4db125b3a5c6..2666b1ed5e9e 100644
--- a/Documentation/filesystems/caching/netfs-api.txt
+++ b/Documentation/filesystems/caching/netfs-api.txt
@@ -184,7 +184,7 @@ This has the following fields:
184 have index children. 184 have index children.
185 185
186 If this function is not supplied or if it returns NULL then the first 186 If this function is not supplied or if it returns NULL then the first
187 cache in the parent's list will be chosed, or failing that, the first 187 cache in the parent's list will be chosen, or failing that, the first
188 cache in the master list. 188 cache in the master list.
189 189
190 (4) A function to retrieve an object's key from the netfs [mandatory]. 190 (4) A function to retrieve an object's key from the netfs [mandatory].
diff --git a/Documentation/filesystems/debugfs.txt b/Documentation/filesystems/debugfs.txt
new file mode 100644
index 000000000000..ed52af60c2d8
--- /dev/null
+++ b/Documentation/filesystems/debugfs.txt
@@ -0,0 +1,158 @@
1Copyright 2009 Jonathan Corbet <corbet@lwn.net>
2
3Debugfs exists as a simple way for kernel developers to make information
4available to user space. Unlike /proc, which is only meant for information
5about a process, or sysfs, which has strict one-value-per-file rules,
6debugfs has no rules at all. Developers can put any information they want
7there. The debugfs filesystem is also intended to not serve as a stable
8ABI to user space; in theory, there are no stability constraints placed on
9files exported there. The real world is not always so simple, though [1];
10even debugfs interfaces are best designed with the idea that they will need
11to be maintained forever.
12
13Debugfs is typically mounted with a command like:
14
15 mount -t debugfs none /sys/kernel/debug
16
17(Or an equivalent /etc/fstab line).
18
19Note that the debugfs API is exported GPL-only to modules.
20
21Code using debugfs should include <linux/debugfs.h>. Then, the first order
22of business will be to create at least one directory to hold a set of
23debugfs files:
24
25 struct dentry *debugfs_create_dir(const char *name, struct dentry *parent);
26
27This call, if successful, will make a directory called name underneath the
28indicated parent directory. If parent is NULL, the directory will be
29created in the debugfs root. On success, the return value is a struct
30dentry pointer which can be used to create files in the directory (and to
31clean it up at the end). A NULL return value indicates that something went
32wrong. If ERR_PTR(-ENODEV) is returned, that is an indication that the
33kernel has been built without debugfs support and none of the functions
34described below will work.
35
36The most general way to create a file within a debugfs directory is with:
37
38 struct dentry *debugfs_create_file(const char *name, mode_t mode,
39 struct dentry *parent, void *data,
40 const struct file_operations *fops);
41
42Here, name is the name of the file to create, mode describes the access
43permissions the file should have, parent indicates the directory which
44should hold the file, data will be stored in the i_private field of the
45resulting inode structure, and fops is a set of file operations which
46implement the file's behavior. At a minimum, the read() and/or write()
47operations should be provided; others can be included as needed. Again,
48the return value will be a dentry pointer to the created file, NULL for
49error, or ERR_PTR(-ENODEV) if debugfs support is missing.
50
51In a number of cases, the creation of a set of file operations is not
52actually necessary; the debugfs code provides a number of helper functions
53for simple situations. Files containing a single integer value can be
54created with any of:
55
56 struct dentry *debugfs_create_u8(const char *name, mode_t mode,
57 struct dentry *parent, u8 *value);
58 struct dentry *debugfs_create_u16(const char *name, mode_t mode,
59 struct dentry *parent, u16 *value);
60 struct dentry *debugfs_create_u32(const char *name, mode_t mode,
61 struct dentry *parent, u32 *value);
62 struct dentry *debugfs_create_u64(const char *name, mode_t mode,
63 struct dentry *parent, u64 *value);
64
65These files support both reading and writing the given value; if a specific
66file should not be written to, simply set the mode bits accordingly. The
67values in these files are in decimal; if hexadecimal is more appropriate,
68the following functions can be used instead:
69
70 struct dentry *debugfs_create_x8(const char *name, mode_t mode,
71 struct dentry *parent, u8 *value);
72 struct dentry *debugfs_create_x16(const char *name, mode_t mode,
73 struct dentry *parent, u16 *value);
74 struct dentry *debugfs_create_x32(const char *name, mode_t mode,
75 struct dentry *parent, u32 *value);
76
77Note that there is no debugfs_create_x64().
78
79These functions are useful as long as the developer knows the size of the
80value to be exported. Some types can have different widths on different
81architectures, though, complicating the situation somewhat. There is a
82function meant to help out in one special case:
83
84 struct dentry *debugfs_create_size_t(const char *name, mode_t mode,
85 struct dentry *parent,
86 size_t *value);
87
88As might be expected, this function will create a debugfs file to represent
89a variable of type size_t.
90
91Boolean values can be placed in debugfs with:
92
93 struct dentry *debugfs_create_bool(const char *name, mode_t mode,
94 struct dentry *parent, u32 *value);
95
96A read on the resulting file will yield either Y (for non-zero values) or
97N, followed by a newline. If written to, it will accept either upper- or
98lower-case values, or 1 or 0. Any other input will be silently ignored.
99
100Finally, a block of arbitrary binary data can be exported with:
101
102 struct debugfs_blob_wrapper {
103 void *data;
104 unsigned long size;
105 };
106
107 struct dentry *debugfs_create_blob(const char *name, mode_t mode,
108 struct dentry *parent,
109 struct debugfs_blob_wrapper *blob);
110
111A read of this file will return the data pointed to by the
112debugfs_blob_wrapper structure. Some drivers use "blobs" as a simple way
113to return several lines of (static) formatted text output. This function
114can be used to export binary information, but there does not appear to be
115any code which does so in the mainline. Note that all files created with
116debugfs_create_blob() are read-only.
117
118There are a couple of other directory-oriented helper functions:
119
120 struct dentry *debugfs_rename(struct dentry *old_dir,
121 struct dentry *old_dentry,
122 struct dentry *new_dir,
123 const char *new_name);
124
125 struct dentry *debugfs_create_symlink(const char *name,
126 struct dentry *parent,
127 const char *target);
128
129A call to debugfs_rename() will give a new name to an existing debugfs
130file, possibly in a different directory. The new_name must not exist prior
131to the call; the return value is old_dentry with updated information.
132Symbolic links can be created with debugfs_create_symlink().
133
134There is one important thing that all debugfs users must take into account:
135there is no automatic cleanup of any directories created in debugfs. If a
136module is unloaded without explicitly removing debugfs entries, the result
137will be a lot of stale pointers and no end of highly antisocial behavior.
138So all debugfs users - at least those which can be built as modules - must
139be prepared to remove all files and directories they create there. A file
140can be removed with:
141
142 void debugfs_remove(struct dentry *dentry);
143
144The dentry value can be NULL, in which case nothing will be removed.
145
146Once upon a time, debugfs users were required to remember the dentry
147pointer for every debugfs file they created so that all files could be
148cleaned up. We live in more civilized times now, though, and debugfs users
149can call:
150
151 void debugfs_remove_recursive(struct dentry *dentry);
152
153If this function is passed a pointer for the dentry corresponding to the
154top-level directory, the entire hierarchy below that directory will be
155removed.
156
157Notes:
158 [1] http://lwn.net/Articles/309298/
diff --git a/Documentation/filesystems/ext4.txt b/Documentation/filesystems/ext4.txt
index 97882df04865..608fdba97b72 100644
--- a/Documentation/filesystems/ext4.txt
+++ b/Documentation/filesystems/ext4.txt
@@ -294,7 +294,7 @@ max_batch_time=usec Maximum amount of time ext4 should wait for
294 amount of time (on average) that it takes to 294 amount of time (on average) that it takes to
295 finish committing a transaction. Call this time 295 finish committing a transaction. Call this time
296 the "commit time". If the time that the 296 the "commit time". If the time that the
297 transactoin has been running is less than the 297 transaction has been running is less than the
298 commit time, ext4 will try sleeping for the 298 commit time, ext4 will try sleeping for the
299 commit time to see if other operations will join 299 commit time to see if other operations will join
300 the transaction. The commit time is capped by 300 the transaction. The commit time is capped by
@@ -328,7 +328,7 @@ noauto_da_alloc replacing existing files via patterns such as
328 journal commit, in the default data=ordered 328 journal commit, in the default data=ordered
329 mode, the data blocks of the new file are forced 329 mode, the data blocks of the new file are forced
330 to disk before the rename() operation is 330 to disk before the rename() operation is
331 commited. This provides roughly the same level 331 committed. This provides roughly the same level
332 of guarantees as ext3, and avoids the 332 of guarantees as ext3, and avoids the
333 "zero-length" problem that can happen when a 333 "zero-length" problem that can happen when a
334 system crashes before the delayed allocation 334 system crashes before the delayed allocation
@@ -358,7 +358,7 @@ written to the journal first, and then to its final location.
358In the event of a crash, the journal can be replayed, bringing both data and 358In the event of a crash, the journal can be replayed, bringing both data and
359metadata into a consistent state. This mode is the slowest except when data 359metadata into a consistent state. This mode is the slowest except when data
360needs to be read from and written to disk at the same time where it 360needs to be read from and written to disk at the same time where it
361outperforms all others modes. Curently ext4 does not have delayed 361outperforms all others modes. Currently ext4 does not have delayed
362allocation support if this data journalling mode is selected. 362allocation support if this data journalling mode is selected.
363 363
364References 364References
diff --git a/Documentation/filesystems/fiemap.txt b/Documentation/filesystems/fiemap.txt
index 1e3defcfe50b..606233cd4618 100644
--- a/Documentation/filesystems/fiemap.txt
+++ b/Documentation/filesystems/fiemap.txt
@@ -204,7 +204,7 @@ fiemap_check_flags() helper:
204 204
205int fiemap_check_flags(struct fiemap_extent_info *fieinfo, u32 fs_flags); 205int fiemap_check_flags(struct fiemap_extent_info *fieinfo, u32 fs_flags);
206 206
207The struct fieinfo should be passed in as recieved from ioctl_fiemap(). The 207The struct fieinfo should be passed in as received from ioctl_fiemap(). The
208set of fiemap flags which the fs understands should be passed via fs_flags. If 208set of fiemap flags which the fs understands should be passed via fs_flags. If
209fiemap_check_flags finds invalid user flags, it will place the bad values in 209fiemap_check_flags finds invalid user flags, it will place the bad values in
210fieinfo->fi_flags and return -EBADR. If the file system gets -EBADR, from 210fieinfo->fi_flags and return -EBADR. If the file system gets -EBADR, from
diff --git a/Documentation/filesystems/gfs2-glocks.txt b/Documentation/filesystems/gfs2-glocks.txt
index 4dae9a3840bf..0494f78d87e4 100644
--- a/Documentation/filesystems/gfs2-glocks.txt
+++ b/Documentation/filesystems/gfs2-glocks.txt
@@ -60,7 +60,7 @@ go_lock | Called for the first local holder of a lock
60go_unlock | Called on the final local unlock of a lock 60go_unlock | Called on the final local unlock of a lock
61go_dump | Called to print content of object for debugfs file, or on 61go_dump | Called to print content of object for debugfs file, or on
62 | error to dump glock to the log. 62 | error to dump glock to the log.
63go_type; | The type of the glock, LM_TYPE_..... 63go_type | The type of the glock, LM_TYPE_.....
64go_min_hold_time | The minimum hold time 64go_min_hold_time | The minimum hold time
65 65
66The minimum hold time for each lock is the time after a remote lock 66The minimum hold time for each lock is the time after a remote lock
diff --git a/Documentation/filesystems/gfs2.txt b/Documentation/filesystems/gfs2.txt
index 593004b6bbab..5e3ab8f3beff 100644
--- a/Documentation/filesystems/gfs2.txt
+++ b/Documentation/filesystems/gfs2.txt
@@ -11,18 +11,15 @@ their I/O so file system consistency is maintained. One of the nifty
11features of GFS is perfect consistency -- changes made to the file system 11features of GFS is perfect consistency -- changes made to the file system
12on one machine show up immediately on all other machines in the cluster. 12on one machine show up immediately on all other machines in the cluster.
13 13
14GFS uses interchangable inter-node locking mechanisms. Different lock 14GFS uses interchangable inter-node locking mechanisms, the currently
15modules can plug into GFS and each file system selects the appropriate 15supported mechanisms are:
16lock module at mount time. Lock modules include:
17 16
18 lock_nolock -- allows gfs to be used as a local file system 17 lock_nolock -- allows gfs to be used as a local file system
19 18
20 lock_dlm -- uses a distributed lock manager (dlm) for inter-node locking 19 lock_dlm -- uses a distributed lock manager (dlm) for inter-node locking
21 The dlm is found at linux/fs/dlm/ 20 The dlm is found at linux/fs/dlm/
22 21
23In addition to interfacing with an external locking manager, a gfs lock 22Lock_dlm depends on user space cluster management systems found
24module is responsible for interacting with external cluster management
25systems. Lock_dlm depends on user space cluster management systems found
26at the URL above. 23at the URL above.
27 24
28To use gfs as a local file system, no external clustering systems are 25To use gfs as a local file system, no external clustering systems are
@@ -31,13 +28,19 @@ needed, simply:
31 $ mkfs -t gfs2 -p lock_nolock -j 1 /dev/block_device 28 $ mkfs -t gfs2 -p lock_nolock -j 1 /dev/block_device
32 $ mount -t gfs2 /dev/block_device /dir 29 $ mount -t gfs2 /dev/block_device /dir
33 30
34GFS2 is not on-disk compatible with previous versions of GFS. 31If you are using Fedora, you need to install the gfs2-utils package
32and, for lock_dlm, you will also need to install the cman package
33and write a cluster.conf as per the documentation.
34
35GFS2 is not on-disk compatible with previous versions of GFS, but it
36is pretty close.
35 37
36The following man pages can be found at the URL above: 38The following man pages can be found at the URL above:
37 gfs2_fsck to repair a filesystem 39 fsck.gfs2 to repair a filesystem
38 gfs2_grow to expand a filesystem online 40 gfs2_grow to expand a filesystem online
39 gfs2_jadd to add journals to a filesystem online 41 gfs2_jadd to add journals to a filesystem online
40 gfs2_tool to manipulate, examine and tune a filesystem 42 gfs2_tool to manipulate, examine and tune a filesystem
41 gfs2_quota to examine and change quota values in a filesystem 43 gfs2_quota to examine and change quota values in a filesystem
44 gfs2_convert to convert a gfs filesystem to gfs2 in-place
42 mount.gfs2 to help mount(8) mount a filesystem 45 mount.gfs2 to help mount(8) mount a filesystem
43 mkfs.gfs2 to make a filesystem 46 mkfs.gfs2 to make a filesystem
diff --git a/Documentation/filesystems/nfs-rdma.txt b/Documentation/filesystems/nfs-rdma.txt
index 85eaeaddd27c..e386f7e4bcee 100644
--- a/Documentation/filesystems/nfs-rdma.txt
+++ b/Documentation/filesystems/nfs-rdma.txt
@@ -100,7 +100,7 @@ Installation
100 $ sudo cp utils/mount/mount.nfs /sbin/mount.nfs 100 $ sudo cp utils/mount/mount.nfs /sbin/mount.nfs
101 101
102 In this location, mount.nfs will be invoked automatically for NFS mounts 102 In this location, mount.nfs will be invoked automatically for NFS mounts
103 by the system mount commmand. 103 by the system mount command.
104 104
105 NOTE: mount.nfs and therefore nfs-utils-1.1.2 or greater is only needed 105 NOTE: mount.nfs and therefore nfs-utils-1.1.2 or greater is only needed
106 on the NFS client machine. You do not need this specific version of 106 on the NFS client machine. You do not need this specific version of
diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt
index ce84cfc9eae0..cd8717a36271 100644
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -366,7 +366,7 @@ just those considered 'most important'. The new vectors are:
366 RES, CAL, TLB -- rescheduling, call and TLB flush interrupts are 366 RES, CAL, TLB -- rescheduling, call and TLB flush interrupts are
367 sent from one CPU to another per the needs of the OS. Typically, 367 sent from one CPU to another per the needs of the OS. Typically,
368 their statistics are used by kernel developers and interested users to 368 their statistics are used by kernel developers and interested users to
369 determine the occurance of interrupt of the given type. 369 determine the occurrence of interrupts of the given type.
370 370
371The above IRQ vectors are displayed only when relevent. For example, 371The above IRQ vectors are displayed only when relevent. For example,
372the threshold vector does not exist on x86_64 platforms. Others are 372the threshold vector does not exist on x86_64 platforms. Others are
@@ -551,7 +551,7 @@ Committed_AS: The amount of memory presently allocated on the system.
551 memory once that memory has been successfully allocated. 551 memory once that memory has been successfully allocated.
552VmallocTotal: total size of vmalloc memory area 552VmallocTotal: total size of vmalloc memory area
553 VmallocUsed: amount of vmalloc area which is used 553 VmallocUsed: amount of vmalloc area which is used
554VmallocChunk: largest contigious block of vmalloc area which is free 554VmallocChunk: largest contiguous block of vmalloc area which is free
555 555
556.............................................................................. 556..............................................................................
557 557
diff --git a/Documentation/filesystems/sysfs-pci.txt b/Documentation/filesystems/sysfs-pci.txt
index 26e4b8bc53ee..85354b32d731 100644
--- a/Documentation/filesystems/sysfs-pci.txt
+++ b/Documentation/filesystems/sysfs-pci.txt
@@ -72,7 +72,7 @@ The 'rom' file is special in that it provides read-only access to the device's
72ROM file, if available. It's disabled by default, however, so applications 72ROM file, if available. It's disabled by default, however, so applications
73should write the string "1" to the file to enable it before attempting a read 73should write the string "1" to the file to enable it before attempting a read
74call, and disable it following the access by writing "0" to the file. Note 74call, and disable it following the access by writing "0" to the file. Note
75that the device must be enabled for a rom read to return data succesfully. 75that the device must be enabled for a rom read to return data successfully.
76In the event a driver is not bound to the device, it can be enabled using the 76In the event a driver is not bound to the device, it can be enabled using the
77'enable' file, documented above. 77'enable' file, documented above.
78 78
diff --git a/Documentation/filesystems/vfat.txt b/Documentation/filesystems/vfat.txt
index 3a5ddc96901a..5147be5e13cd 100644
--- a/Documentation/filesystems/vfat.txt
+++ b/Documentation/filesystems/vfat.txt
@@ -124,10 +124,10 @@ sys_immutable -- If set, ATTR_SYS attribute on FAT is handled as
124flush -- If set, the filesystem will try to flush to disk more 124flush -- If set, the filesystem will try to flush to disk more
125 early than normal. Not set by default. 125 early than normal. Not set by default.
126 126
127rodir -- FAT has the ATTR_RO (read-only) attribute. But on Windows, 127rodir -- FAT has the ATTR_RO (read-only) attribute. On Windows,
128 the ATTR_RO of the directory will be just ignored actually, 128 the ATTR_RO of the directory will just be ignored,
129 and is used by only applications as flag. E.g. it's setted 129 and is used only by applications as a flag (e.g. it's set
130 for the customized folder. 130 for the customized folder).
131 131
132 If you want to use ATTR_RO as read-only flag even for 132 If you want to use ATTR_RO as read-only flag even for
133 the directory, set this option. 133 the directory, set this option.