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-rw-r--r--Documentation/filesystems/Locking7
-rw-r--r--Documentation/filesystems/omfs.txt106
-rw-r--r--Documentation/filesystems/proc.txt48
-rw-r--r--Documentation/filesystems/relay.txt10
-rw-r--r--Documentation/filesystems/vfat.txt8
-rw-r--r--Documentation/filesystems/vfs.txt6
6 files changed, 180 insertions, 5 deletions
diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking
index 8b22d7d8b991..680fb566b928 100644
--- a/Documentation/filesystems/Locking
+++ b/Documentation/filesystems/Locking
@@ -510,6 +510,7 @@ prototypes:
510 void (*close)(struct vm_area_struct*); 510 void (*close)(struct vm_area_struct*);
511 int (*fault)(struct vm_area_struct*, struct vm_fault *); 511 int (*fault)(struct vm_area_struct*, struct vm_fault *);
512 int (*page_mkwrite)(struct vm_area_struct *, struct page *); 512 int (*page_mkwrite)(struct vm_area_struct *, struct page *);
513 int (*access)(struct vm_area_struct *, unsigned long, void*, int, int);
513 514
514locking rules: 515locking rules:
515 BKL mmap_sem PageLocked(page) 516 BKL mmap_sem PageLocked(page)
@@ -517,6 +518,7 @@ open: no yes
517close: no yes 518close: no yes
518fault: no yes 519fault: no yes
519page_mkwrite: no yes no 520page_mkwrite: no yes no
521access: no yes
520 522
521 ->page_mkwrite() is called when a previously read-only page is 523 ->page_mkwrite() is called when a previously read-only page is
522about to become writeable. The file system is responsible for 524about to become writeable. The file system is responsible for
@@ -525,6 +527,11 @@ taking to lock out truncate, the page range should be verified to be
525within i_size. The page mapping should also be checked that it is not 527within i_size. The page mapping should also be checked that it is not
526NULL. 528NULL.
527 529
530 ->access() is called when get_user_pages() fails in
531acces_process_vm(), typically used to debug a process through
532/proc/pid/mem or ptrace. This function is needed only for
533VM_IO | VM_PFNMAP VMAs.
534
528================================================================================ 535================================================================================
529 Dubious stuff 536 Dubious stuff
530 537
diff --git a/Documentation/filesystems/omfs.txt b/Documentation/filesystems/omfs.txt
new file mode 100644
index 000000000000..1d0d41ff5c65
--- /dev/null
+++ b/Documentation/filesystems/omfs.txt
@@ -0,0 +1,106 @@
1Optimized MPEG Filesystem (OMFS)
2
3Overview
4========
5
6OMFS is a filesystem created by SonicBlue for use in the ReplayTV DVR
7and Rio Karma MP3 player. The filesystem is extent-based, utilizing
8block sizes from 2k to 8k, with hash-based directories. This
9filesystem driver may be used to read and write disks from these
10devices.
11
12Note, it is not recommended that this FS be used in place of a general
13filesystem for your own streaming media device. Native Linux filesystems
14will likely perform better.
15
16More information is available at:
17
18 http://linux-karma.sf.net/
19
20Various utilities, including mkomfs and omfsck, are included with
21omfsprogs, available at:
22
23 http://bobcopeland.com/karma/
24
25Instructions are included in its README.
26
27Options
28=======
29
30OMFS supports the following mount-time options:
31
32 uid=n - make all files owned by specified user
33 gid=n - make all files owned by specified group
34 umask=xxx - set permission umask to xxx
35 fmask=xxx - set umask to xxx for files
36 dmask=xxx - set umask to xxx for directories
37
38Disk format
39===========
40
41OMFS discriminates between "sysblocks" and normal data blocks. The sysblock
42group consists of super block information, file metadata, directory structures,
43and extents. Each sysblock has a header containing CRCs of the entire
44sysblock, and may be mirrored in successive blocks on the disk. A sysblock may
45have a smaller size than a data block, but since they are both addressed by the
46same 64-bit block number, any remaining space in the smaller sysblock is
47unused.
48
49Sysblock header information:
50
51struct omfs_header {
52 __be64 h_self; /* FS block where this is located */
53 __be32 h_body_size; /* size of useful data after header */
54 __be16 h_crc; /* crc-ccitt of body_size bytes */
55 char h_fill1[2];
56 u8 h_version; /* version, always 1 */
57 char h_type; /* OMFS_INODE_X */
58 u8 h_magic; /* OMFS_IMAGIC */
59 u8 h_check_xor; /* XOR of header bytes before this */
60 __be32 h_fill2;
61};
62
63Files and directories are both represented by omfs_inode:
64
65struct omfs_inode {
66 struct omfs_header i_head; /* header */
67 __be64 i_parent; /* parent containing this inode */
68 __be64 i_sibling; /* next inode in hash bucket */
69 __be64 i_ctime; /* ctime, in milliseconds */
70 char i_fill1[35];
71 char i_type; /* OMFS_[DIR,FILE] */
72 __be32 i_fill2;
73 char i_fill3[64];
74 char i_name[OMFS_NAMELEN]; /* filename */
75 __be64 i_size; /* size of file, in bytes */
76};
77
78Directories in OMFS are implemented as a large hash table. Filenames are
79hashed then prepended into the bucket list beginning at OMFS_DIR_START.
80Lookup requires hashing the filename, then seeking across i_sibling pointers
81until a match is found on i_name. Empty buckets are represented by block
82pointers with all-1s (~0).
83
84A file is an omfs_inode structure followed by an extent table beginning at
85OMFS_EXTENT_START:
86
87struct omfs_extent_entry {
88 __be64 e_cluster; /* start location of a set of blocks */
89 __be64 e_blocks; /* number of blocks after e_cluster */
90};
91
92struct omfs_extent {
93 __be64 e_next; /* next extent table location */
94 __be32 e_extent_count; /* total # extents in this table */
95 __be32 e_fill;
96 struct omfs_extent_entry e_entry; /* start of extent entries */
97};
98
99Each extent holds the block offset followed by number of blocks allocated to
100the extent. The final extent in each table is a terminator with e_cluster
101being ~0 and e_blocks being ones'-complement of the total number of blocks
102in the table.
103
104If this table overflows, a continuation inode is written and pointed to by
105e_next. These have a header but lack the rest of the inode structure.
106
diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt
index 7f268f327d75..64557821ee59 100644
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -296,6 +296,7 @@ Table 1-4: Kernel info in /proc
296 uptime System uptime 296 uptime System uptime
297 version Kernel version 297 version Kernel version
298 video bttv info of video resources (2.4) 298 video bttv info of video resources (2.4)
299 vmallocinfo Show vmalloced areas
299.............................................................................. 300..............................................................................
300 301
301You can, for example, check which interrupts are currently in use and what 302You can, for example, check which interrupts are currently in use and what
@@ -557,6 +558,49 @@ VmallocTotal: total size of vmalloc memory area
557 VmallocUsed: amount of vmalloc area which is used 558 VmallocUsed: amount of vmalloc area which is used
558VmallocChunk: largest contigious block of vmalloc area which is free 559VmallocChunk: largest contigious block of vmalloc area which is free
559 560
561..............................................................................
562
563vmallocinfo:
564
565Provides information about vmalloced/vmaped areas. One line per area,
566containing the virtual address range of the area, size in bytes,
567caller information of the creator, and optional information depending
568on the kind of area :
569
570 pages=nr number of pages
571 phys=addr if a physical address was specified
572 ioremap I/O mapping (ioremap() and friends)
573 vmalloc vmalloc() area
574 vmap vmap()ed pages
575 user VM_USERMAP area
576 vpages buffer for pages pointers was vmalloced (huge area)
577 N<node>=nr (Only on NUMA kernels)
578 Number of pages allocated on memory node <node>
579
580> cat /proc/vmallocinfo
5810xffffc20000000000-0xffffc20000201000 2101248 alloc_large_system_hash+0x204 ...
582 /0x2c0 pages=512 vmalloc N0=128 N1=128 N2=128 N3=128
5830xffffc20000201000-0xffffc20000302000 1052672 alloc_large_system_hash+0x204 ...
584 /0x2c0 pages=256 vmalloc N0=64 N1=64 N2=64 N3=64
5850xffffc20000302000-0xffffc20000304000 8192 acpi_tb_verify_table+0x21/0x4f...
586 phys=7fee8000 ioremap
5870xffffc20000304000-0xffffc20000307000 12288 acpi_tb_verify_table+0x21/0x4f...
588 phys=7fee7000 ioremap
5890xffffc2000031d000-0xffffc2000031f000 8192 init_vdso_vars+0x112/0x210
5900xffffc2000031f000-0xffffc2000032b000 49152 cramfs_uncompress_init+0x2e ...
591 /0x80 pages=11 vmalloc N0=3 N1=3 N2=2 N3=3
5920xffffc2000033a000-0xffffc2000033d000 12288 sys_swapon+0x640/0xac0 ...
593 pages=2 vmalloc N1=2
5940xffffc20000347000-0xffffc2000034c000 20480 xt_alloc_table_info+0xfe ...
595 /0x130 [x_tables] pages=4 vmalloc N0=4
5960xffffffffa0000000-0xffffffffa000f000 61440 sys_init_module+0xc27/0x1d00 ...
597 pages=14 vmalloc N2=14
5980xffffffffa000f000-0xffffffffa0014000 20480 sys_init_module+0xc27/0x1d00 ...
599 pages=4 vmalloc N1=4
6000xffffffffa0014000-0xffffffffa0017000 12288 sys_init_module+0xc27/0x1d00 ...
601 pages=2 vmalloc N1=2
6020xffffffffa0017000-0xffffffffa0022000 45056 sys_init_module+0xc27/0x1d00 ...
603 pages=10 vmalloc N0=10
560 604
5611.3 IDE devices in /proc/ide 6051.3 IDE devices in /proc/ide
562---------------------------- 606----------------------------
@@ -887,7 +931,7 @@ group_prealloc max_to_scan mb_groups mb_history min_to_scan order2_req
887stats stream_req 931stats stream_req
888 932
889mb_groups: 933mb_groups:
890This file gives the details of mutiblock allocator buddy cache of free blocks 934This file gives the details of multiblock allocator buddy cache of free blocks
891 935
892mb_history: 936mb_history:
893Multiblock allocation history. 937Multiblock allocation history.
@@ -1430,7 +1474,7 @@ used because pages_free(1355) is smaller than watermark + protection[2]
1430normal page requirement. If requirement is DMA zone(index=0), protection[0] 1474normal page requirement. If requirement is DMA zone(index=0), protection[0]
1431(=0) is used. 1475(=0) is used.
1432 1476
1433zone[i]'s protection[j] is calculated by following exprssion. 1477zone[i]'s protection[j] is calculated by following expression.
1434 1478
1435(i < j): 1479(i < j):
1436 zone[i]->protection[j] 1480 zone[i]->protection[j]
diff --git a/Documentation/filesystems/relay.txt b/Documentation/filesystems/relay.txt
index 094f2d2f38b1..510b722667ac 100644
--- a/Documentation/filesystems/relay.txt
+++ b/Documentation/filesystems/relay.txt
@@ -294,6 +294,16 @@ user-defined data with a channel, and is immediately available
294(including in create_buf_file()) via chan->private_data or 294(including in create_buf_file()) via chan->private_data or
295buf->chan->private_data. 295buf->chan->private_data.
296 296
297Buffer-only channels
298--------------------
299
300These channels have no files associated and can be created with
301relay_open(NULL, NULL, ...). Such channels are useful in scenarios such
302as when doing early tracing in the kernel, before the VFS is up. In these
303cases, one may open a buffer-only channel and then call
304relay_late_setup_files() when the kernel is ready to handle files,
305to expose the buffered data to the userspace.
306
297Channel 'modes' 307Channel 'modes'
298--------------- 308---------------
299 309
diff --git a/Documentation/filesystems/vfat.txt b/Documentation/filesystems/vfat.txt
index 2d5e1e582e13..bbac4f1d9056 100644
--- a/Documentation/filesystems/vfat.txt
+++ b/Documentation/filesystems/vfat.txt
@@ -96,6 +96,14 @@ shortname=lower|win95|winnt|mixed
96 emulate the Windows 95 rule for create. 96 emulate the Windows 95 rule for create.
97 Default setting is `lower'. 97 Default setting is `lower'.
98 98
99tz=UTC -- Interpret timestamps as UTC rather than local time.
100 This option disables the conversion of timestamps
101 between local time (as used by Windows on FAT) and UTC
102 (which Linux uses internally). This is particuluarly
103 useful when mounting devices (like digital cameras)
104 that are set to UTC in order to avoid the pitfalls of
105 local time.
106
99<bool>: 0,1,yes,no,true,false 107<bool>: 0,1,yes,no,true,false
100 108
101TODO 109TODO
diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt
index b7522c6cbae3..c4d348dabe94 100644
--- a/Documentation/filesystems/vfs.txt
+++ b/Documentation/filesystems/vfs.txt
@@ -143,7 +143,7 @@ struct file_system_type {
143 143
144The get_sb() method has the following arguments: 144The get_sb() method has the following arguments:
145 145
146 struct file_system_type *fs_type: decribes the filesystem, partly initialized 146 struct file_system_type *fs_type: describes the filesystem, partly initialized
147 by the specific filesystem code 147 by the specific filesystem code
148 148
149 int flags: mount flags 149 int flags: mount flags
@@ -895,9 +895,9 @@ struct dentry_operations {
895 iput() yourself 895 iput() yourself
896 896
897 d_dname: called when the pathname of a dentry should be generated. 897 d_dname: called when the pathname of a dentry should be generated.
898 Usefull for some pseudo filesystems (sockfs, pipefs, ...) to delay 898 Useful for some pseudo filesystems (sockfs, pipefs, ...) to delay
899 pathname generation. (Instead of doing it when dentry is created, 899 pathname generation. (Instead of doing it when dentry is created,
900 its done only when the path is needed.). Real filesystems probably 900 it's done only when the path is needed.). Real filesystems probably
901 dont want to use it, because their dentries are present in global 901 dont want to use it, because their dentries are present in global
902 dcache hash, so their hash should be an invariant. As no lock is 902 dcache hash, so their hash should be an invariant. As no lock is
903 held, d_dname() should not try to modify the dentry itself, unless 903 held, d_dname() should not try to modify the dentry itself, unless