diff options
author | Felix Blyakher <felixb@sgi.com> | 2009-04-01 17:58:39 -0400 |
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committer | Felix Blyakher <felixb@sgi.com> | 2009-04-01 17:58:39 -0400 |
commit | f36345ff9a4a77f2cc576a2777b6256d5c8798fa (patch) | |
tree | 7ae4c607f6baae74060c2e385f744e171fbbf92b /Documentation/filesystems | |
parent | 1aacc064e029f0017384e463121b98f06d3a2cc3 (diff) | |
parent | 8b53ef33d9d8fa5f771ae11cc6a6e7bc0182beec (diff) |
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 into for-linus
Diffstat (limited to 'Documentation/filesystems')
-rw-r--r-- | Documentation/filesystems/Locking | 2 | ||||
-rw-r--r-- | Documentation/filesystems/ext4.txt | 30 | ||||
-rw-r--r-- | Documentation/filesystems/proc.txt | 21 | ||||
-rw-r--r-- | Documentation/filesystems/sysfs-pci.txt | 10 |
4 files changed, 38 insertions, 25 deletions
diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking index 4e78ce677843..76efe5b71d7d 100644 --- a/Documentation/filesystems/Locking +++ b/Documentation/filesystems/Locking | |||
@@ -505,7 +505,7 @@ prototypes: | |||
505 | void (*open)(struct vm_area_struct*); | 505 | void (*open)(struct vm_area_struct*); |
506 | void (*close)(struct vm_area_struct*); | 506 | void (*close)(struct vm_area_struct*); |
507 | int (*fault)(struct vm_area_struct*, struct vm_fault *); | 507 | int (*fault)(struct vm_area_struct*, struct vm_fault *); |
508 | int (*page_mkwrite)(struct vm_area_struct *, struct page *); | 508 | int (*page_mkwrite)(struct vm_area_struct *, struct vm_fault *); |
509 | int (*access)(struct vm_area_struct *, unsigned long, void*, int, int); | 509 | int (*access)(struct vm_area_struct *, unsigned long, void*, int, int); |
510 | 510 | ||
511 | locking rules: | 511 | locking rules: |
diff --git a/Documentation/filesystems/ext4.txt b/Documentation/filesystems/ext4.txt index cec829bc7291..97882df04865 100644 --- a/Documentation/filesystems/ext4.txt +++ b/Documentation/filesystems/ext4.txt | |||
@@ -85,7 +85,7 @@ Note: More extensive information for getting started with ext4 can be | |||
85 | * extent format more robust in face of on-disk corruption due to magics, | 85 | * extent format more robust in face of on-disk corruption due to magics, |
86 | * internal redundancy in tree | 86 | * internal redundancy in tree |
87 | * improved file allocation (multi-block alloc) | 87 | * improved file allocation (multi-block alloc) |
88 | * fix 32000 subdirectory limit | 88 | * lift 32000 subdirectory limit imposed by i_links_count[1] |
89 | * nsec timestamps for mtime, atime, ctime, create time | 89 | * nsec timestamps for mtime, atime, ctime, create time |
90 | * inode version field on disk (NFSv4, Lustre) | 90 | * inode version field on disk (NFSv4, Lustre) |
91 | * reduced e2fsck time via uninit_bg feature | 91 | * reduced e2fsck time via uninit_bg feature |
@@ -100,6 +100,9 @@ Note: More extensive information for getting started with ext4 can be | |||
100 | * efficent new ordered mode in JBD2 and ext4(avoid using buffer head to force | 100 | * efficent new ordered mode in JBD2 and ext4(avoid using buffer head to force |
101 | the ordering) | 101 | the ordering) |
102 | 102 | ||
103 | [1] Filesystems with a block size of 1k may see a limit imposed by the | ||
104 | directory hash tree having a maximum depth of two. | ||
105 | |||
103 | 2.2 Candidate features for future inclusion | 106 | 2.2 Candidate features for future inclusion |
104 | 107 | ||
105 | * Online defrag (patches available but not well tested) | 108 | * Online defrag (patches available but not well tested) |
@@ -180,8 +183,8 @@ commit=nrsec (*) Ext4 can be told to sync all its data and metadata | |||
180 | performance. | 183 | performance. |
181 | 184 | ||
182 | barrier=<0|1(*)> This enables/disables the use of write barriers in | 185 | barrier=<0|1(*)> This enables/disables the use of write barriers in |
183 | the jbd code. barrier=0 disables, barrier=1 enables. | 186 | barrier(*) the jbd code. barrier=0 disables, barrier=1 enables. |
184 | This also requires an IO stack which can support | 187 | nobarrier This also requires an IO stack which can support |
185 | barriers, and if jbd gets an error on a barrier | 188 | barriers, and if jbd gets an error on a barrier |
186 | write, it will disable again with a warning. | 189 | write, it will disable again with a warning. |
187 | Write barriers enforce proper on-disk ordering | 190 | Write barriers enforce proper on-disk ordering |
@@ -189,6 +192,9 @@ barrier=<0|1(*)> This enables/disables the use of write barriers in | |||
189 | safe to use, at some performance penalty. If | 192 | safe to use, at some performance penalty. If |
190 | your disks are battery-backed in one way or another, | 193 | your disks are battery-backed in one way or another, |
191 | disabling barriers may safely improve performance. | 194 | disabling barriers may safely improve performance. |
195 | The mount options "barrier" and "nobarrier" can | ||
196 | also be used to enable or disable barriers, for | ||
197 | consistency with other ext4 mount options. | ||
192 | 198 | ||
193 | inode_readahead=n This tuning parameter controls the maximum | 199 | inode_readahead=n This tuning parameter controls the maximum |
194 | number of inode table blocks that ext4's inode | 200 | number of inode table blocks that ext4's inode |
@@ -310,6 +316,24 @@ journal_ioprio=prio The I/O priority (from 0 to 7, where 0 is the | |||
310 | a slightly higher priority than the default I/O | 316 | a slightly higher priority than the default I/O |
311 | priority. | 317 | priority. |
312 | 318 | ||
319 | auto_da_alloc(*) Many broken applications don't use fsync() when | ||
320 | noauto_da_alloc replacing existing files via patterns such as | ||
321 | fd = open("foo.new")/write(fd,..)/close(fd)/ | ||
322 | rename("foo.new", "foo"), or worse yet, | ||
323 | fd = open("foo", O_TRUNC)/write(fd,..)/close(fd). | ||
324 | If auto_da_alloc is enabled, ext4 will detect | ||
325 | the replace-via-rename and replace-via-truncate | ||
326 | patterns and force that any delayed allocation | ||
327 | blocks are allocated such that at the next | ||
328 | journal commit, in the default data=ordered | ||
329 | mode, the data blocks of the new file are forced | ||
330 | to disk before the rename() operation is | ||
331 | commited. This provides roughly the same level | ||
332 | of guarantees as ext3, and avoids the | ||
333 | "zero-length" problem that can happen when a | ||
334 | system crashes before the delayed allocation | ||
335 | blocks are forced to disk. | ||
336 | |||
313 | Data Mode | 337 | Data Mode |
314 | ========= | 338 | ========= |
315 | There are 3 different data modes: | 339 | There are 3 different data modes: |
diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt index 830bad7cce0f..efc4fd9f40ce 100644 --- a/Documentation/filesystems/proc.txt +++ b/Documentation/filesystems/proc.txt | |||
@@ -940,27 +940,6 @@ Table 1-10: Files in /proc/fs/ext4/<devname> | |||
940 | File Content | 940 | File Content |
941 | mb_groups details of multiblock allocator buddy cache of free blocks | 941 | mb_groups details of multiblock allocator buddy cache of free blocks |
942 | mb_history multiblock allocation history | 942 | mb_history multiblock allocation history |
943 | stats controls whether the multiblock allocator should start | ||
944 | collecting statistics, which are shown during the unmount | ||
945 | group_prealloc the multiblock allocator will round up allocation | ||
946 | requests to a multiple of this tuning parameter if the | ||
947 | stripe size is not set in the ext4 superblock | ||
948 | max_to_scan The maximum number of extents the multiblock allocator | ||
949 | will search to find the best extent | ||
950 | min_to_scan The minimum number of extents the multiblock allocator | ||
951 | will search to find the best extent | ||
952 | order2_req Tuning parameter which controls the minimum size for | ||
953 | requests (as a power of 2) where the buddy cache is | ||
954 | used | ||
955 | stream_req Files which have fewer blocks than this tunable | ||
956 | parameter will have their blocks allocated out of a | ||
957 | block group specific preallocation pool, so that small | ||
958 | files are packed closely together. Each large file | ||
959 | will have its blocks allocated out of its own unique | ||
960 | preallocation pool. | ||
961 | inode_readahead Tuning parameter which controls the maximum number of | ||
962 | inode table blocks that ext4's inode table readahead | ||
963 | algorithm will pre-read into the buffer cache | ||
964 | .............................................................................. | 943 | .............................................................................. |
965 | 944 | ||
966 | 945 | ||
diff --git a/Documentation/filesystems/sysfs-pci.txt b/Documentation/filesystems/sysfs-pci.txt index 9f8740ca3f3b..26e4b8bc53ee 100644 --- a/Documentation/filesystems/sysfs-pci.txt +++ b/Documentation/filesystems/sysfs-pci.txt | |||
@@ -12,6 +12,7 @@ that support it. For example, a given bus might look like this: | |||
12 | | |-- enable | 12 | | |-- enable |
13 | | |-- irq | 13 | | |-- irq |
14 | | |-- local_cpus | 14 | | |-- local_cpus |
15 | | |-- remove | ||
15 | | |-- resource | 16 | | |-- resource |
16 | | |-- resource0 | 17 | | |-- resource0 |
17 | | |-- resource1 | 18 | | |-- resource1 |
@@ -36,6 +37,7 @@ files, each with their own function. | |||
36 | enable Whether the device is enabled (ascii, rw) | 37 | enable Whether the device is enabled (ascii, rw) |
37 | irq IRQ number (ascii, ro) | 38 | irq IRQ number (ascii, ro) |
38 | local_cpus nearby CPU mask (cpumask, ro) | 39 | local_cpus nearby CPU mask (cpumask, ro) |
40 | remove remove device from kernel's list (ascii, wo) | ||
39 | resource PCI resource host addresses (ascii, ro) | 41 | resource PCI resource host addresses (ascii, ro) |
40 | resource0..N PCI resource N, if present (binary, mmap) | 42 | resource0..N PCI resource N, if present (binary, mmap) |
41 | resource0_wc..N_wc PCI WC map resource N, if prefetchable (binary, mmap) | 43 | resource0_wc..N_wc PCI WC map resource N, if prefetchable (binary, mmap) |
@@ -46,6 +48,7 @@ files, each with their own function. | |||
46 | 48 | ||
47 | ro - read only file | 49 | ro - read only file |
48 | rw - file is readable and writable | 50 | rw - file is readable and writable |
51 | wo - write only file | ||
49 | mmap - file is mmapable | 52 | mmap - file is mmapable |
50 | ascii - file contains ascii text | 53 | ascii - file contains ascii text |
51 | binary - file contains binary data | 54 | binary - file contains binary data |
@@ -73,6 +76,13 @@ that the device must be enabled for a rom read to return data succesfully. | |||
73 | In the event a driver is not bound to the device, it can be enabled using the | 76 | In the event a driver is not bound to the device, it can be enabled using the |
74 | 'enable' file, documented above. | 77 | 'enable' file, documented above. |
75 | 78 | ||
79 | The 'remove' file is used to remove the PCI device, by writing a non-zero | ||
80 | integer to the file. This does not involve any kind of hot-plug functionality, | ||
81 | e.g. powering off the device. The device is removed from the kernel's list of | ||
82 | PCI devices, the sysfs directory for it is removed, and the device will be | ||
83 | removed from any drivers attached to it. Removal of PCI root buses is | ||
84 | disallowed. | ||
85 | |||
76 | Accessing legacy resources through sysfs | 86 | Accessing legacy resources through sysfs |
77 | ---------------------------------------- | 87 | ---------------------------------------- |
78 | 88 | ||