diff options
Diffstat (limited to 'Documentation/filesystems')
25 files changed, 320 insertions, 302 deletions
diff --git a/Documentation/filesystems/9p.rst b/Documentation/filesystems/9p.rst index 2995279ddc24..7b5964bc8865 100644 --- a/Documentation/filesystems/9p.rst +++ b/Documentation/filesystems/9p.rst @@ -18,7 +18,7 @@ and Maya Gokhale. Additional development by Greg Watson The best detailed explanation of the Linux implementation and applications of the 9p client is available in the form of a USENIX paper: - http://www.usenix.org/events/usenix05/tech/freenix/hensbergen.html + https://www.usenix.org/events/usenix05/tech/freenix/hensbergen.html Other applications are described in the following papers: diff --git a/Documentation/filesystems/afs.rst b/Documentation/filesystems/afs.rst index cada9464d6bd..0abb155ac666 100644 --- a/Documentation/filesystems/afs.rst +++ b/Documentation/filesystems/afs.rst @@ -190,7 +190,7 @@ Security Secure operations are initiated by acquiring a key using the klog program. A very primitive klog program is available at: - http://people.redhat.com/~dhowells/rxrpc/klog.c + https://people.redhat.com/~dhowells/rxrpc/klog.c This should be compiled by:: diff --git a/Documentation/filesystems/autofs-mount-control.rst b/Documentation/filesystems/autofs-mount-control.rst index 2903aed92316..bf4b511cdbe8 100644 --- a/Documentation/filesystems/autofs-mount-control.rst +++ b/Documentation/filesystems/autofs-mount-control.rst @@ -391,7 +391,7 @@ variation uses the path and optionally in.type field of struct args_ismountpoint set to an autofs mount type. The call returns 1 if this is a mount point and sets out.devid field to the device number of the mount and out.magic field to the relevant super block magic number (described below) or 0 if -it isn't a mountpoint. In both cases the the device number (as returned +it isn't a mountpoint. In both cases the device number (as returned by new_encode_dev()) is returned in out.devid field. If supplied with a file descriptor we're looking for a specific mount, @@ -399,12 +399,12 @@ not necessarily at the top of the mounted stack. In this case the path the descriptor corresponds to is considered a mountpoint if it is itself a mountpoint or contains a mount, such as a multi-mount without a root mount. In this case we return 1 if the descriptor corresponds to a mount -point and and also returns the super magic of the covering mount if there +point and also returns the super magic of the covering mount if there is one or 0 if it isn't a mountpoint. If a path is supplied (and the ioctlfd field is set to -1) then the path is looked up and is checked to see if it is the root of a mount. If a type is also given we are looking for a particular autofs mount and if -a match isn't found a fail is returned. If the the located path is the +a match isn't found a fail is returned. If the located path is the root of a mount 1 is returned along with the super magic of the mount or 0 otherwise. diff --git a/Documentation/filesystems/caching/cachefiles.rst b/Documentation/filesystems/caching/cachefiles.rst index 65d3db476765..e58bc1fd312a 100644 --- a/Documentation/filesystems/caching/cachefiles.rst +++ b/Documentation/filesystems/caching/cachefiles.rst @@ -348,7 +348,7 @@ data cached therein; nor is it permitted to create new files in the cache. There are policy source files available in: - http://people.redhat.com/~dhowells/fscache/cachefilesd-0.8.tar.bz2 + https://people.redhat.com/~dhowells/fscache/cachefilesd-0.8.tar.bz2 and later versions. In that tarball, see the files:: diff --git a/Documentation/filesystems/caching/operations.rst b/Documentation/filesystems/caching/operations.rst index f7ddcc028939..9983e1675447 100644 --- a/Documentation/filesystems/caching/operations.rst +++ b/Documentation/filesystems/caching/operations.rst @@ -27,7 +27,7 @@ data storage and retrieval routines. Its operations are represented by fscache_operation structs, though these are usually embedded into some other structure. -This facility is available to and expected to be be used by the cache backends, +This facility is available to and expected to be used by the cache backends, and FS-Cache will create operations and pass them off to the appropriate cache backend for completion. diff --git a/Documentation/filesystems/coda.rst b/Documentation/filesystems/coda.rst index 84c860c89887..bdde7e4e010b 100644 --- a/Documentation/filesystems/coda.rst +++ b/Documentation/filesystems/coda.rst @@ -524,7 +524,7 @@ kernel support. Description This call is made to determine the ViceFid and filetype of - a directory entry. The directory entry requested carries name name + a directory entry. The directory entry requested carries name 'name' and Venus will search the directory identified by cfs_lookup_in.VFid. The result may indicate that the name does not exist, or that difficulty was encountered in finding it (e.g. due to disconnection). @@ -886,7 +886,7 @@ kernel support. none Description - Remove the directory with name name from the directory + Remove the directory with name 'name' from the directory identified by VFid. .. Note:: The attributes of the parent directory should be returned since diff --git a/Documentation/filesystems/configfs.rst b/Documentation/filesystems/configfs.rst index f8941954c667..1d3d6f4a82a9 100644 --- a/Documentation/filesystems/configfs.rst +++ b/Documentation/filesystems/configfs.rst @@ -226,7 +226,7 @@ filename. configfs_attribute->ca_mode specifies the file permissions. If an attribute is readable and provides a ->show method, that method will be called whenever userspace asks for a read(2) on the attribute. If an attribute is writable and provides a ->store method, that method will be -be called whenever userspace asks for a write(2) on the attribute. +called whenever userspace asks for a write(2) on the attribute. struct configfs_bin_attribute ============================= diff --git a/Documentation/filesystems/directory-locking.rst b/Documentation/filesystems/directory-locking.rst index de12016ee419..504ba940c36c 100644 --- a/Documentation/filesystems/directory-locking.rst +++ b/Documentation/filesystems/directory-locking.rst @@ -28,7 +28,7 @@ RENAME_EXCHANGE in flags argument) lock both. In any case, if the target already exists, lock it. If the source is a non-directory, lock it. If we need to lock both, lock them in inode pointer order. Then call the method. All locks are exclusive. -NB: we might get away with locking the the source (and target in exchange +NB: we might get away with locking the source (and target in exchange case) shared. 5) link creation. Locking rules: @@ -56,7 +56,7 @@ rules: * call the method. All ->i_rwsem are taken exclusive. Again, we might get away with locking -the the source (and target in exchange case) shared. +the source (and target in exchange case) shared. The rules above obviously guarantee that all directories that are going to be read, modified or removed by method will be locked by caller. diff --git a/Documentation/filesystems/f2fs.rst b/Documentation/filesystems/f2fs.rst index 099d45ac8d8f..a11d329542f9 100644 --- a/Documentation/filesystems/f2fs.rst +++ b/Documentation/filesystems/f2fs.rst @@ -101,164 +101,170 @@ Mount Options ============= -====================== ============================================================ -background_gc=%s Turn on/off cleaning operations, namely garbage - collection, triggered in background when I/O subsystem is - idle. If background_gc=on, it will turn on the garbage - collection and if background_gc=off, garbage collection - will be turned off. If background_gc=sync, it will turn - on synchronous garbage collection running in background. - Default value for this option is on. So garbage - collection is on by default. -disable_roll_forward Disable the roll-forward recovery routine -norecovery Disable the roll-forward recovery routine, mounted read- - only (i.e., -o ro,disable_roll_forward) -discard/nodiscard Enable/disable real-time discard in f2fs, if discard is - enabled, f2fs will issue discard/TRIM commands when a - segment is cleaned. -no_heap Disable heap-style segment allocation which finds free - segments for data from the beginning of main area, while - for node from the end of main area. -nouser_xattr Disable Extended User Attributes. Note: xattr is enabled - by default if CONFIG_F2FS_FS_XATTR is selected. -noacl Disable POSIX Access Control List. Note: acl is enabled - by default if CONFIG_F2FS_FS_POSIX_ACL is selected. -active_logs=%u Support configuring the number of active logs. In the - current design, f2fs supports only 2, 4, and 6 logs. - Default number is 6. -disable_ext_identify Disable the extension list configured by mkfs, so f2fs - does not aware of cold files such as media files. -inline_xattr Enable the inline xattrs feature. -noinline_xattr Disable the inline xattrs feature. -inline_xattr_size=%u Support configuring inline xattr size, it depends on - flexible inline xattr feature. -inline_data Enable the inline data feature: New created small(<~3.4k) - files can be written into inode block. -inline_dentry Enable the inline dir feature: data in new created - directory entries can be written into inode block. The - space of inode block which is used to store inline - dentries is limited to ~3.4k. -noinline_dentry Disable the inline dentry feature. -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. -nobarrier This option can be used if underlying storage guarantees - its cached data should be written to the novolatile area. - If this option is set, no cache_flush commands are issued - but f2fs still guarantees the write ordering of all the - data writes. -fastboot This option is used when a system wants to reduce mount - time as much as possible, even though normal performance - can be sacrificed. -extent_cache Enable an extent cache based on rb-tree, it can cache - as many as extent which map between contiguous logical - address and physical address per inode, resulting in - increasing the cache hit ratio. Set by default. -noextent_cache Disable an extent cache based on rb-tree explicitly, see - the above extent_cache mount option. -noinline_data Disable the inline data feature, inline data feature is - enabled by default. -data_flush Enable data flushing before checkpoint in order to - persist data of regular and symlink. -reserve_root=%d Support configuring reserved space which is used for - allocation from a privileged user with specified uid or - gid, unit: 4KB, the default limit is 0.2% of user blocks. -resuid=%d The user ID which may use the reserved blocks. -resgid=%d The group ID which may use the reserved blocks. -fault_injection=%d Enable fault injection in all supported types with - specified injection rate. -fault_type=%d Support configuring fault injection type, should be - enabled with fault_injection option, fault type value - is shown below, it supports single or combined type. - - =================== =========== - Type_Name Type_Value - =================== =========== - FAULT_KMALLOC 0x000000001 - FAULT_KVMALLOC 0x000000002 - FAULT_PAGE_ALLOC 0x000000004 - FAULT_PAGE_GET 0x000000008 - FAULT_ALLOC_BIO 0x000000010 - FAULT_ALLOC_NID 0x000000020 - FAULT_ORPHAN 0x000000040 - FAULT_BLOCK 0x000000080 - FAULT_DIR_DEPTH 0x000000100 - FAULT_EVICT_INODE 0x000000200 - FAULT_TRUNCATE 0x000000400 - FAULT_READ_IO 0x000000800 - FAULT_CHECKPOINT 0x000001000 - FAULT_DISCARD 0x000002000 - FAULT_WRITE_IO 0x000004000 - =================== =========== -mode=%s Control block allocation mode which supports "adaptive" - and "lfs". In "lfs" mode, there should be no random - writes towards main area. -io_bits=%u Set the bit size of write IO requests. It should be set - with "mode=lfs". -usrquota Enable plain user disk quota accounting. -grpquota Enable plain group disk quota accounting. -prjquota Enable plain project quota accounting. -usrjquota=<file> Appoint specified file and type during mount, so that quota -grpjquota=<file> information can be properly updated during recovery flow, -prjjquota=<file> <quota file>: must be in root directory; -jqfmt=<quota type> <quota type>: [vfsold,vfsv0,vfsv1]. -offusrjquota Turn off user journelled quota. -offgrpjquota Turn off group journelled quota. -offprjjquota Turn off project journelled quota. -quota Enable plain user disk quota accounting. -noquota Disable all plain disk quota option. -whint_mode=%s Control which write hints are passed down to block - layer. This supports "off", "user-based", and - "fs-based". In "off" mode (default), f2fs does not pass - down hints. In "user-based" mode, f2fs tries to pass - down hints given by users. And in "fs-based" mode, f2fs - passes down hints with its policy. -alloc_mode=%s Adjust block allocation policy, which supports "reuse" - and "default". -fsync_mode=%s Control the policy of fsync. Currently supports "posix", - "strict", and "nobarrier". In "posix" mode, which is - default, fsync will follow POSIX semantics and does a - light operation to improve the filesystem performance. - In "strict" mode, fsync will be heavy and behaves in line - with xfs, ext4 and btrfs, where xfstest generic/342 will - pass, but the performance will regress. "nobarrier" is - based on "posix", but doesn't issue flush command for - non-atomic files likewise "nobarrier" mount option. +======================== ============================================================ +background_gc=%s Turn on/off cleaning operations, namely garbage + collection, triggered in background when I/O subsystem is + idle. If background_gc=on, it will turn on the garbage + collection and if background_gc=off, garbage collection + will be turned off. If background_gc=sync, it will turn + on synchronous garbage collection running in background. + Default value for this option is on. So garbage + collection is on by default. +disable_roll_forward Disable the roll-forward recovery routine +norecovery Disable the roll-forward recovery routine, mounted read- + only (i.e., -o ro,disable_roll_forward) +discard/nodiscard Enable/disable real-time discard in f2fs, if discard is + enabled, f2fs will issue discard/TRIM commands when a + segment is cleaned. +no_heap Disable heap-style segment allocation which finds free + segments for data from the beginning of main area, while + for node from the end of main area. +nouser_xattr Disable Extended User Attributes. Note: xattr is enabled + by default if CONFIG_F2FS_FS_XATTR is selected. +noacl Disable POSIX Access Control List. Note: acl is enabled + by default if CONFIG_F2FS_FS_POSIX_ACL is selected. +active_logs=%u Support configuring the number of active logs. In the + current design, f2fs supports only 2, 4, and 6 logs. + Default number is 6. +disable_ext_identify Disable the extension list configured by mkfs, so f2fs + does not aware of cold files such as media files. +inline_xattr Enable the inline xattrs feature. +noinline_xattr Disable the inline xattrs feature. +inline_xattr_size=%u Support configuring inline xattr size, it depends on + flexible inline xattr feature. +inline_data Enable the inline data feature: New created small(<~3.4k) + files can be written into inode block. +inline_dentry Enable the inline dir feature: data in new created + directory entries can be written into inode block. The + space of inode block which is used to store inline + dentries is limited to ~3.4k. +noinline_dentry Disable the inline dentry feature. +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. +nobarrier This option can be used if underlying storage guarantees + its cached data should be written to the novolatile area. + If this option is set, no cache_flush commands are issued + but f2fs still guarantees the write ordering of all the + data writes. +fastboot This option is used when a system wants to reduce mount + time as much as possible, even though normal performance + can be sacrificed. +extent_cache Enable an extent cache based on rb-tree, it can cache + as many as extent which map between contiguous logical + address and physical address per inode, resulting in + increasing the cache hit ratio. Set by default. +noextent_cache Disable an extent cache based on rb-tree explicitly, see + the above extent_cache mount option. +noinline_data Disable the inline data feature, inline data feature is + enabled by default. +data_flush Enable data flushing before checkpoint in order to + persist data of regular and symlink. +reserve_root=%d Support configuring reserved space which is used for + allocation from a privileged user with specified uid or + gid, unit: 4KB, the default limit is 0.2% of user blocks. +resuid=%d The user ID which may use the reserved blocks. +resgid=%d The group ID which may use the reserved blocks. +fault_injection=%d Enable fault injection in all supported types with + specified injection rate. +fault_type=%d Support configuring fault injection type, should be + enabled with fault_injection option, fault type value + is shown below, it supports single or combined type. + + =================== =========== + Type_Name Type_Value + =================== =========== + FAULT_KMALLOC 0x000000001 + FAULT_KVMALLOC 0x000000002 + FAULT_PAGE_ALLOC 0x000000004 + FAULT_PAGE_GET 0x000000008 + FAULT_ALLOC_BIO 0x000000010 + FAULT_ALLOC_NID 0x000000020 + FAULT_ORPHAN 0x000000040 + FAULT_BLOCK 0x000000080 + FAULT_DIR_DEPTH 0x000000100 + FAULT_EVICT_INODE 0x000000200 + FAULT_TRUNCATE 0x000000400 + FAULT_READ_IO 0x000000800 + FAULT_CHECKPOINT 0x000001000 + FAULT_DISCARD 0x000002000 + FAULT_WRITE_IO 0x000004000 + =================== =========== +mode=%s Control block allocation mode which supports "adaptive" + and "lfs". In "lfs" mode, there should be no random + writes towards main area. +io_bits=%u Set the bit size of write IO requests. It should be set + with "mode=lfs". +usrquota Enable plain user disk quota accounting. +grpquota Enable plain group disk quota accounting. +prjquota Enable plain project quota accounting. +usrjquota=<file> Appoint specified file and type during mount, so that quota +grpjquota=<file> information can be properly updated during recovery flow, +prjjquota=<file> <quota file>: must be in root directory; +jqfmt=<quota type> <quota type>: [vfsold,vfsv0,vfsv1]. +offusrjquota Turn off user journelled quota. +offgrpjquota Turn off group journelled quota. +offprjjquota Turn off project journelled quota. +quota Enable plain user disk quota accounting. +noquota Disable all plain disk quota option. +whint_mode=%s Control which write hints are passed down to block + layer. This supports "off", "user-based", and + "fs-based". In "off" mode (default), f2fs does not pass + down hints. In "user-based" mode, f2fs tries to pass + down hints given by users. And in "fs-based" mode, f2fs + passes down hints with its policy. +alloc_mode=%s Adjust block allocation policy, which supports "reuse" + and "default". +fsync_mode=%s Control the policy of fsync. Currently supports "posix", + "strict", and "nobarrier". In "posix" mode, which is + default, fsync will follow POSIX semantics and does a + light operation to improve the filesystem performance. + In "strict" mode, fsync will be heavy and behaves in line + with xfs, ext4 and btrfs, where xfstest generic/342 will + pass, but the performance will regress. "nobarrier" is + based on "posix", but doesn't issue flush command for + non-atomic files likewise "nobarrier" mount option. test_dummy_encryption test_dummy_encryption=%s - Enable dummy encryption, which provides a fake fscrypt - context. The fake fscrypt context is used by xfstests. - The argument may be either "v1" or "v2", in order to - select the corresponding fscrypt policy version. -checkpoint=%s[:%u[%]] Set to "disable" to turn off checkpointing. Set to "enable" - to reenable checkpointing. Is enabled by default. While - disabled, any unmounting or unexpected shutdowns will cause - the filesystem contents to appear as they did when the - filesystem was mounted with that option. - While mounting with checkpoint=disabled, the filesystem must - run garbage collection to ensure that all available space can - be used. If this takes too much time, the mount may return - EAGAIN. You may optionally add a value to indicate how much - of the disk you would be willing to temporarily give up to - avoid additional garbage collection. This can be given as a - number of blocks, or as a percent. For instance, mounting - with checkpoint=disable:100% would always succeed, but it may - hide up to all remaining free space. The actual space that - would be unusable can be viewed at /sys/fs/f2fs/<disk>/unusable - This space is reclaimed once checkpoint=enable. -compress_algorithm=%s Control compress algorithm, currently f2fs supports "lzo", - "lz4", "zstd" and "lzo-rle" algorithm. -compress_log_size=%u Support configuring compress cluster size, the size will - be 4KB * (1 << %u), 16KB is minimum size, also it's - default size. -compress_extension=%s Support adding specified extension, so that f2fs can enable - compression on those corresponding files, e.g. if all files - with '.ext' has high compression rate, we can set the '.ext' - on compression extension list and enable compression on - these file by default rather than to enable it via ioctl. - For other files, we can still enable compression via ioctl. -====================== ============================================================ + Enable dummy encryption, which provides a fake fscrypt + context. The fake fscrypt context is used by xfstests. + The argument may be either "v1" or "v2", in order to + select the corresponding fscrypt policy version. +checkpoint=%s[:%u[%]] Set to "disable" to turn off checkpointing. Set to "enable" + to reenable checkpointing. Is enabled by default. While + disabled, any unmounting or unexpected shutdowns will cause + the filesystem contents to appear as they did when the + filesystem was mounted with that option. + While mounting with checkpoint=disabled, the filesystem must + run garbage collection to ensure that all available space can + be used. If this takes too much time, the mount may return + EAGAIN. You may optionally add a value to indicate how much + of the disk you would be willing to temporarily give up to + avoid additional garbage collection. This can be given as a + number of blocks, or as a percent. For instance, mounting + with checkpoint=disable:100% would always succeed, but it may + hide up to all remaining free space. The actual space that + would be unusable can be viewed at /sys/fs/f2fs/<disk>/unusable + This space is reclaimed once checkpoint=enable. +compress_algorithm=%s Control compress algorithm, currently f2fs supports "lzo", + "lz4", "zstd" and "lzo-rle" algorithm. +compress_log_size=%u Support configuring compress cluster size, the size will + be 4KB * (1 << %u), 16KB is minimum size, also it's + default size. +compress_extension=%s Support adding specified extension, so that f2fs can enable + compression on those corresponding files, e.g. if all files + with '.ext' has high compression rate, we can set the '.ext' + on compression extension list and enable compression on + these file by default rather than to enable it via ioctl. + For other files, we can still enable compression via ioctl. +inlinecrypt When possible, encrypt/decrypt the contents of encrypted + files using the blk-crypto framework rather than + filesystem-layer encryption. This allows the use of + inline encryption hardware. The on-disk format is + unaffected. For more details, see + Documentation/block/inline-encryption.rst. +======================== ============================================================ Debugfs Entries =============== diff --git a/Documentation/filesystems/fscrypt.rst b/Documentation/filesystems/fscrypt.rst index f517af8ec11c..423c5a0daf45 100644 --- a/Documentation/filesystems/fscrypt.rst +++ b/Documentation/filesystems/fscrypt.rst @@ -1158,7 +1158,7 @@ setxattr() because of the special semantics of the encryption xattr. were to be added to or removed from anything other than an empty directory.) These structs are defined as follows:: - #define FS_KEY_DERIVATION_NONCE_SIZE 16 + #define FSCRYPT_FILE_NONCE_SIZE 16 #define FSCRYPT_KEY_DESCRIPTOR_SIZE 8 struct fscrypt_context_v1 { @@ -1167,7 +1167,7 @@ directory.) These structs are defined as follows:: u8 filenames_encryption_mode; u8 flags; u8 master_key_descriptor[FSCRYPT_KEY_DESCRIPTOR_SIZE]; - u8 nonce[FS_KEY_DERIVATION_NONCE_SIZE]; + u8 nonce[FSCRYPT_FILE_NONCE_SIZE]; }; #define FSCRYPT_KEY_IDENTIFIER_SIZE 16 @@ -1178,7 +1178,7 @@ directory.) These structs are defined as follows:: u8 flags; u8 __reserved[4]; u8 master_key_identifier[FSCRYPT_KEY_IDENTIFIER_SIZE]; - u8 nonce[FS_KEY_DERIVATION_NONCE_SIZE]; + u8 nonce[FSCRYPT_FILE_NONCE_SIZE]; }; The context structs contain the same information as the corresponding @@ -1204,6 +1204,18 @@ buffer. Some filesystems, such as UBIFS, already use temporary buffers regardless of encryption. Other filesystems, such as ext4 and F2FS, have to allocate bounce pages specially for encryption. +Fscrypt is also able to use inline encryption hardware instead of the +kernel crypto API for en/decryption of file contents. When possible, +and if directed to do so (by specifying the 'inlinecrypt' mount option +for an ext4/F2FS filesystem), it adds encryption contexts to bios and +uses blk-crypto to perform the en/decryption instead of making use of +the above read/write path changes. Of course, even if directed to +make use of inline encryption, fscrypt will only be able to do so if +either hardware inline encryption support is available for the +selected encryption algorithm or CONFIG_BLK_INLINE_ENCRYPTION_FALLBACK +is selected. If neither is the case, fscrypt will fall back to using +the above mentioned read/write path changes for en/decryption. + Filename hashing and encoding ----------------------------- @@ -1250,11 +1262,14 @@ Tests To test fscrypt, use xfstests, which is Linux's de facto standard filesystem test suite. First, run all the tests in the "encrypt" -group on the relevant filesystem(s). For example, to test ext4 and +group on the relevant filesystem(s). One can also run the tests +with the 'inlinecrypt' mount option to test the implementation for +inline encryption support. For example, to test ext4 and f2fs encryption using `kvm-xfstests <https://github.com/tytso/xfstests-bld/blob/master/Documentation/kvm-quickstart.md>`_:: kvm-xfstests -c ext4,f2fs -g encrypt + kvm-xfstests -c ext4,f2fs -g encrypt -m inlinecrypt UBIFS encryption can also be tested this way, but it should be done in a separate command, and it takes some time for kvm-xfstests to set up @@ -1276,6 +1291,7 @@ This tests the encrypted I/O paths more thoroughly. To do this with kvm-xfstests, use the "encrypt" filesystem configuration:: kvm-xfstests -c ext4/encrypt,f2fs/encrypt -g auto + kvm-xfstests -c ext4/encrypt,f2fs/encrypt -g auto -m inlinecrypt Because this runs many more tests than "-g encrypt" does, it takes much longer to run; so also consider using `gce-xfstests @@ -1283,3 +1299,4 @@ much longer to run; so also consider using `gce-xfstests instead of kvm-xfstests:: gce-xfstests -c ext4/encrypt,f2fs/encrypt -g auto + gce-xfstests -c ext4/encrypt,f2fs/encrypt -g auto -m inlinecrypt diff --git a/Documentation/filesystems/fsverity.rst b/Documentation/filesystems/fsverity.rst index a95536b6443c..6c8944f6f0f7 100644 --- a/Documentation/filesystems/fsverity.rst +++ b/Documentation/filesystems/fsverity.rst @@ -659,7 +659,7 @@ weren't already directly answered in other parts of this document. retrofit existing filesystems with new consistency mechanisms. Data journalling is available on ext4, but is very slow. - - Rebuilding the the Merkle tree after every write, which would be + - Rebuilding the Merkle tree after every write, which would be extremely inefficient. Alternatively, a different authenticated dictionary structure such as an "authenticated skiplist" could be used. However, this would be far more complex. diff --git a/Documentation/filesystems/hfs.rst b/Documentation/filesystems/hfs.rst index ab17a005e9b1..776015c80e3f 100644 --- a/Documentation/filesystems/hfs.rst +++ b/Documentation/filesystems/hfs.rst @@ -76,7 +76,7 @@ Creating HFS filesystems The hfsutils package from Robert Leslie contains a program called hformat that can be used to create HFS filesystem. See -<http://www.mars.org/home/rob/proj/hfs/> for details. +<https://www.mars.org/home/rob/proj/hfs/> for details. Credits diff --git a/Documentation/filesystems/hpfs.rst b/Documentation/filesystems/hpfs.rst index 0db152278572..7e0dd2f4373e 100644 --- a/Documentation/filesystems/hpfs.rst +++ b/Documentation/filesystems/hpfs.rst @@ -7,7 +7,7 @@ Read/Write HPFS 2.09 1998-2004, Mikulas Patocka :email: mikulas@artax.karlin.mff.cuni.cz -:homepage: http://artax.karlin.mff.cuni.cz/~mikulas/vyplody/hpfs/index-e.cgi +:homepage: https://artax.karlin.mff.cuni.cz/~mikulas/vyplody/hpfs/index-e.cgi Credits ======= diff --git a/Documentation/filesystems/locking.rst b/Documentation/filesystems/locking.rst index 318605de83f3..64f94a18d97e 100644 --- a/Documentation/filesystems/locking.rst +++ b/Documentation/filesystems/locking.rst @@ -433,15 +433,15 @@ prototypes:: locking rules: -========== ============= ================= ========= +====================== ============= ================= ========= ops inode->i_lock blocked_lock_lock may block -========== ============= ================= ========= +====================== ============= ================= ========= lm_notify: yes yes no lm_grant: no no no lm_break: yes no no lm_change yes no no lm_breaker_owns_lease: no no no -========== ============= ================= ========= +====================== ============= ================= ========= buffer_head =========== @@ -467,7 +467,6 @@ prototypes:: int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); int (*direct_access) (struct block_device *, sector_t, void **, unsigned long *); - int (*media_changed) (struct gendisk *); void (*unlock_native_capacity) (struct gendisk *); int (*revalidate_disk) (struct gendisk *); int (*getgeo)(struct block_device *, struct hd_geometry *); @@ -483,14 +482,13 @@ release: yes ioctl: no compat_ioctl: no direct_access: no -media_changed: no unlock_native_capacity: no revalidate_disk: no getgeo: no swap_slot_free_notify: no (see below) ======================= =================== -media_changed, unlock_native_capacity and revalidate_disk are called only from +unlock_native_capacity and revalidate_disk are called only from check_disk_change(). swap_slot_free_notify is called with swap_lock and sometimes the page lock @@ -616,9 +614,9 @@ prototypes:: locking rules: -============= ======== =========================== +============= ========= =========================== ops mmap_lock PageLocked(page) -============= ======== =========================== +============= ========= =========================== open: yes close: yes fault: yes can return with page locked @@ -626,7 +624,7 @@ map_pages: yes page_mkwrite: yes can return with page locked pfn_mkwrite: yes access: yes -============= ======== =========================== +============= ========= =========================== ->fault() is called when a previously not present pte is about to be faulted in. The filesystem must find and return the page associated diff --git a/Documentation/filesystems/mount_api.rst b/Documentation/filesystems/mount_api.rst index dea22d64f060..29c169c68961 100644 --- a/Documentation/filesystems/mount_api.rst +++ b/Documentation/filesystems/mount_api.rst @@ -213,7 +213,7 @@ The filesystem context points to a table of operations:: void (*free)(struct fs_context *fc); int (*dup)(struct fs_context *fc, struct fs_context *src_fc); int (*parse_param)(struct fs_context *fc, - struct struct fs_parameter *param); + struct fs_parameter *param); int (*parse_monolithic)(struct fs_context *fc, void *data); int (*get_tree)(struct fs_context *fc); int (*reconfigure)(struct fs_context *fc); @@ -247,7 +247,7 @@ manage the filesystem context. They are as follows: * :: int (*parse_param)(struct fs_context *fc, - struct struct fs_parameter *param); + struct fs_parameter *param); Called when a parameter is being added to the filesystem context. param points to the key name and maybe a value object. VFS-specific options diff --git a/Documentation/filesystems/nfs/rpc-server-gss.rst b/Documentation/filesystems/nfs/rpc-server-gss.rst index 812754576845..abed4a2b1b82 100644 --- a/Documentation/filesystems/nfs/rpc-server-gss.rst +++ b/Documentation/filesystems/nfs/rpc-server-gss.rst @@ -10,12 +10,12 @@ purposes of authentication.) RPCGSS is specified in a few IETF documents: - - RFC2203 v1: http://tools.ietf.org/rfc/rfc2203.txt - - RFC5403 v2: http://tools.ietf.org/rfc/rfc5403.txt + - RFC2203 v1: https://tools.ietf.org/rfc/rfc2203.txt + - RFC5403 v2: https://tools.ietf.org/rfc/rfc5403.txt and there is a 3rd version being proposed: - - http://tools.ietf.org/id/draft-williams-rpcsecgssv3.txt + - https://tools.ietf.org/id/draft-williams-rpcsecgssv3.txt (At draft n. 02 at the time of writing) Background diff --git a/Documentation/filesystems/omfs.rst b/Documentation/filesystems/omfs.rst index 4c8bb3074169..a104c25b7a2f 100644 --- a/Documentation/filesystems/omfs.rst +++ b/Documentation/filesystems/omfs.rst @@ -24,7 +24,7 @@ More information is available at: Various utilities, including mkomfs and omfsck, are included with omfsprogs, available at: - http://bobcopeland.com/karma/ + https://bobcopeland.com/karma/ Instructions are included in its README. diff --git a/Documentation/filesystems/overlayfs.rst b/Documentation/filesystems/overlayfs.rst index fcda5d6ba9ac..8ea83a51c266 100644 --- a/Documentation/filesystems/overlayfs.rst +++ b/Documentation/filesystems/overlayfs.rst @@ -328,7 +328,7 @@ the time of copy (on-demand vs. up-front). Multiple lower layers --------------------- -Multiple lower layers can now be given using the the colon (":") as a +Multiple lower layers can now be given using the colon (":") as a separator character between the directory names. For example: mount -t overlay overlay -olowerdir=/lower1:/lower2:/lower3 /merged diff --git a/Documentation/filesystems/path-lookup.rst b/Documentation/filesystems/path-lookup.rst index f46b05e9b96c..c482e1619e77 100644 --- a/Documentation/filesystems/path-lookup.rst +++ b/Documentation/filesystems/path-lookup.rst @@ -43,15 +43,15 @@ characters, and "components" that are sequences of one or more non-"``/``" characters. These form two kinds of paths. Those that start with slashes are "absolute" and start from the filesystem root. The others are "relative" and start from the current directory, or -from some other location specified by a file descriptor given to a -"``XXXat``" system call such as `openat() <openat_>`_. +from some other location specified by a file descriptor given to +"``*at()``" system calls such as `openat() <openat_>`_. .. _execveat: http://man7.org/linux/man-pages/man2/execveat.2.html It is tempting to describe the second kind as starting with a component, but that isn't always accurate: a pathname can lack both slashes and components, it can be empty, in other words. This is -generally forbidden in POSIX, but some of those "xxx``at``" system calls +generally forbidden in POSIX, but some of those "``*at()``" system calls in Linux permit it when the ``AT_EMPTY_PATH`` flag is given. For example, if you have an open file descriptor on an executable file you can execute it by calling `execveat() <execveat_>`_ passing @@ -69,17 +69,17 @@ pathname that is just slashes have a final component. If it does exist, it could be "``.``" or "``..``" which are handled quite differently from other components. -.. _POSIX: http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap04.html#tag_04_12 +.. _POSIX: https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap04.html#tag_04_12 If a pathname ends with a slash, such as "``/tmp/foo/``" it might be tempting to consider that to have an empty final component. In many ways that would lead to correct results, but not always. In particular, ``mkdir()`` and ``rmdir()`` each create or remove a directory named by the final component, and they are required to work with pathnames -ending in "``/``". According to POSIX_ +ending in "``/``". According to POSIX_: - A pathname that contains at least one non- <slash> character and - that ends with one or more trailing <slash> characters shall not + A pathname that contains at least one non-<slash> character and + that ends with one or more trailing <slash> characters shall not be resolved successfully unless the last pathname component before the trailing <slash> characters names an existing directory or a directory entry that is to be created for a directory immediately @@ -229,7 +229,7 @@ happened to be looking at a dentry that was moved in this way, it might end up continuing the search down the wrong chain, and so miss out on part of the correct chain. -The name-lookup process (``d_lookup()``) does _not_ try to prevent this +The name-lookup process (``d_lookup()``) does *not* try to prevent this from happening, but only to detect when it happens. ``rename_lock`` is a seqlock that is updated whenever any dentry is renamed. If ``d_lookup`` finds that a rename happened while it @@ -376,7 +376,7 @@ table, and the mount point hash table. Bringing it together with ``struct nameidata`` ---------------------------------------------- -.. _First edition Unix: http://minnie.tuhs.org/cgi-bin/utree.pl?file=V1/u2.s +.. _First edition Unix: https://minnie.tuhs.org/cgi-bin/utree.pl?file=V1/u2.s Throughout the process of walking a path, the current status is stored in a ``struct nameidata``, "namei" being the traditional name - dating @@ -398,7 +398,7 @@ held. ``struct qstr last`` ~~~~~~~~~~~~~~~~~~~~ -This is a string together with a length (i.e. _not_ ``nul`` terminated) +This is a string together with a length (i.e. *not* ``nul`` terminated) that is the "next" component in the pathname. ``int last_type`` @@ -655,8 +655,8 @@ This pattern of "try RCU-walk, if that fails try REF-walk" can be clearly seen in functions like ``filename_lookup()``, ``filename_parentat()``, ``filename_mountpoint()``, ``do_filp_open()``, and ``do_file_open_root()``. These five -correspond roughly to the four ``path_``* functions we met earlier, -each of which calls ``link_path_walk()``. The ``path_*`` functions are +correspond roughly to the four ``path_*()`` functions we met earlier, +each of which calls ``link_path_walk()``. The ``path_*()`` functions are called using different mode flags until a mode is found which works. They are first called with ``LOOKUP_RCU`` set to request "RCU-walk". If that fails with the error ``ECHILD`` they are called again with no @@ -720,7 +720,7 @@ against a dentry. The length and name pointer are copied into local variables, then ``read_seqcount_retry()`` is called to confirm the two are consistent, and only then is ``->d_compare()`` called. When standard filename comparison is used, ``dentry_cmp()`` is called -instead. Notably it does _not_ use ``read_seqcount_retry()``, but +instead. Notably it does *not* use ``read_seqcount_retry()``, but instead has a large comment explaining why the consistency guarantee isn't necessary. A subsequent ``read_seqcount_retry()`` will be sufficient to catch any problem that could occur at this point. @@ -928,7 +928,7 @@ if anything goes wrong it is much safer to just abort and try a more sedate approach. The emphasis here is "try quickly and check". It should probably be -"try quickly _and carefully,_ then check". The fact that checking is +"try quickly *and carefully*, then check". The fact that checking is needed is a reminder that the system is dynamic and only a limited number of things are safe at all. The most likely cause of errors in this whole process is assuming something is safe when in reality it @@ -1265,7 +1265,7 @@ Symlinks are different it seems. Both reading a symlink (with ``readlink()``) and looking up a symlink on the way to some other destination can update the atime on that symlink. -.. _clearest statement: http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap04.html#tag_04_08 +.. _clearest statement: https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap04.html#tag_04_08 It is not clear why this is the case; POSIX has little to say on the subject. The `clearest statement`_ is that, if a particular implementation @@ -1365,7 +1365,7 @@ as well as blocking ".." if it would jump outside the starting point. resolution of "..". Magic-links are also blocked. ``LOOKUP_IN_ROOT`` resolves all path components as though the starting point -were the filesystem root. ``nd_jump_root()`` brings the resolution back to to +were the filesystem root. ``nd_jump_root()`` brings the resolution back to the starting point, and ".." at the starting point will act as a no-op. As with ``LOOKUP_BENEATH``, ``rename_lock`` and ``mount_lock`` are used to detect attacks against ".." resolution. Magic-links are also blocked. diff --git a/Documentation/filesystems/proc.rst b/Documentation/filesystems/proc.rst index 996f3cfe7030..e024a9efffd8 100644 --- a/Documentation/filesystems/proc.rst +++ b/Documentation/filesystems/proc.rst @@ -123,10 +123,10 @@ show you how you can use /proc/sys to change settings. The directory /proc contains (among other things) one subdirectory for each process running on the system, which is named after the process ID (PID). -The link self points to the process reading the file system. Each process +The link 'self' points to the process reading the file system. Each process subdirectory has the entries listed in Table 1-1. -Note that an open a file descriptor to /proc/<pid> or to any of its +Note that an open file descriptor to /proc/<pid> or to any of its contained files or subdirectories does not prevent <pid> being reused for some other process in the event that <pid> exits. Operations on open /proc/<pid> file descriptors corresponding to dead processes @@ -220,7 +220,7 @@ file /proc/PID/status. It fields are described in table 1-2. The statm file contains more detailed information about the process memory usage. Its seven fields are explained in Table 1-3. The stat file -contains details information about the process itself. Its fields are +contains detailed information about the process itself. Its fields are explained in Table 1-4. (for SMP CONFIG users) @@ -545,7 +545,7 @@ encoded manner. The codes are the following: hg huge page advise flag nh no huge page advise flag mg mergable advise flag - bt - arm64 BTI guarded page + bt arm64 BTI guarded page == ======================================= Note that there is no guarantee that every flag and associated mnemonic will @@ -782,7 +782,7 @@ SPU For this case the APIC will generate the interrupt with a IRQ vector of 0xff. This might also be generated by chipset bugs. -RES, CAL, TLB] +RES, CAL, TLB rescheduling, call and TLB flush interrupts are sent from one CPU to another per the needs of the OS. Typically, their statistics are used by kernel developers and interested users to @@ -794,7 +794,7 @@ suppressed when the system is a uniprocessor. As of this writing, only i386 and x86_64 platforms support the new IRQ vector displays. Of some interest is the introduction of the /proc/irq directory to 2.4. -It could be used to set IRQ to CPU affinity, this means that you can "hook" an +It could be used to set IRQ to CPU affinity. This means that you can "hook" an IRQ to only one CPU, or to exclude a CPU of handling IRQs. The contents of the irq subdir is one subdir for each IRQ, and two files; default_smp_affinity and prof_cpu_mask. @@ -808,7 +808,7 @@ For example:: smp_affinity smp_affinity is a bitmask, in which you can specify which CPUs can handle the -IRQ, you can set it by doing:: +IRQ. You can set it by doing:: > echo 1 > /proc/irq/10/smp_affinity @@ -821,7 +821,7 @@ The contents of each smp_affinity file is the same by default:: ffffffff There is an alternate interface, smp_affinity_list which allows specifying -a cpu range instead of a bitmask:: +a CPU range instead of a bitmask:: > cat /proc/irq/0/smp_affinity_list 1024-1031 @@ -835,7 +835,7 @@ reports itself as being attached. This hardware locality information does not include information about any possible driver locality preference. prof_cpu_mask specifies which CPUs are to be profiled by the system wide -profiler. Default value is ffffffff (all cpus if there are only 32 of them). +profiler. Default value is ffffffff (all CPUs if there are only 32 of them). The way IRQs are routed is handled by the IO-APIC, and it's Round Robin between all the CPUs which are allowed to handle it. As usual the kernel has @@ -897,7 +897,7 @@ pagetypeinfo:: Fragmentation avoidance in the kernel works by grouping pages of different migrate types into the same contiguous regions of memory called page blocks. -A page block is typically the size of the default hugepage size e.g. 2MB on +A page block is typically the size of the default hugepage size, e.g. 2MB on X86-64. By keeping pages grouped based on their ability to move, the kernel can reclaim pages within a page block to satisfy a high-order allocation. @@ -965,7 +965,7 @@ varies by architecture and compile options. The following is from a ShmemPmdMapped: 0 kB MemTotal - Total usable ram (i.e. physical ram minus a few reserved + Total usable RAM (i.e. physical RAM minus a few reserved bits and the kernel binary code) MemFree The sum of LowFree+HighFree @@ -996,7 +996,7 @@ Inactive Memory which has been less recently used. It is more eligible to be reclaimed for other purposes HighTotal, HighFree - Highmem is all memory above ~860MB of physical memory + Highmem is all memory above ~860MB of physical memory. Highmem areas are for use by userspace programs, or for the pagecache. The kernel must use tricks to access this memory, making it slower to access than lowmem. @@ -1078,7 +1078,7 @@ Committed_AS using 1G. This 1G is memory which has been "committed" to by the VM and can be used at any time by the allocating application. With strict overcommit enabled on the system - (mode 2 in 'vm.overcommit_memory'),allocations which would + (mode 2 in 'vm.overcommit_memory'), allocations which would exceed the CommitLimit (detailed above) will not be permitted. This is useful if one needs to guarantee that processes will not fail due to lack of memory once that memory has been @@ -1099,7 +1099,7 @@ vmallocinfo Provides information about vmalloced/vmaped areas. One line per area, containing the virtual address range of the area, size in bytes, caller information of the creator, and optional information depending -on the kind of area : +on the kind of area: ========== =================================================== pages=nr number of pages @@ -1144,21 +1144,21 @@ on the kind of area : softirqs ~~~~~~~~ -Provides counts of softirq handlers serviced since boot time, for each cpu. +Provides counts of softirq handlers serviced since boot time, for each CPU. :: > cat /proc/softirqs - CPU0 CPU1 CPU2 CPU3 + CPU0 CPU1 CPU2 CPU3 HI: 0 0 0 0 - TIMER: 27166 27120 27097 27034 + TIMER: 27166 27120 27097 27034 NET_TX: 0 0 0 17 NET_RX: 42 0 0 39 - BLOCK: 0 0 107 1121 - TASKLET: 0 0 0 290 - SCHED: 27035 26983 26971 26746 - HRTIMER: 0 0 0 0 - RCU: 1678 1769 2178 2250 + BLOCK: 0 0 107 1121 + TASKLET: 0 0 0 290 + SCHED: 27035 26983 26971 26746 + HRTIMER: 0 0 0 0 + RCU: 1678 1769 2178 2250 1.3 IDE devices in /proc/ide @@ -1169,7 +1169,7 @@ the kernel is aware. There is one subdirectory for each IDE controller, the file drivers and a link for each IDE device, pointing to the device directory in the controller specific subtree. -The file drivers contains general information about the drivers used for the +The file 'drivers' contains general information about the drivers used for the IDE devices:: > cat /proc/ide/drivers @@ -1409,7 +1409,7 @@ These directories contain the four files shown in Table 1-10. ------------------------- Information about the available and actually used tty's can be found in the -directory /proc/tty.You'll find entries for drivers and line disciplines in +directory /proc/tty. You'll find entries for drivers and line disciplines in this directory, as shown in Table 1-11. @@ -1471,9 +1471,9 @@ second). The meanings of the columns are as follows, from left to right: - iowait: In a word, iowait stands for waiting for I/O to complete. But there are several problems: - 1. Cpu will not wait for I/O to complete, iowait is the time that a task is - waiting for I/O to complete. When cpu goes into idle state for - outstanding task io, another task will be scheduled on this CPU. + 1. CPU will not wait for I/O to complete, iowait is the time that a task is + waiting for I/O to complete. When CPU goes into idle state for + outstanding task I/O, another task will be scheduled on this CPU. 2. In a multi-core CPU, the task waiting for I/O to complete is not running on any CPU, so the iowait of each CPU is difficult to calculate. 3. The value of iowait field in /proc/stat will decrease in certain @@ -1529,8 +1529,8 @@ in Table 1-12, below. mb_groups details of multiblock allocator buddy cache of free blocks ============== ========================================================== -2.0 /proc/consoles ------------------- +1.10 /proc/consoles +------------------- Shows registered system console lines. To see which character device lines are currently used for the system console @@ -1590,10 +1590,9 @@ production system. Set up a development machine and test to make sure that everything works the way you want it to. You may have no alternative but to reboot the machine once an error has been made. -To change a value, simply echo the new value into the file. An example is -given below in the section on the file system data. You need to be root to do -this. You can create your own boot script to perform this every time your -system boots. +To change a value, simply echo the new value into the file. +You need to be root to do this. You can create your own boot script +to perform this every time your system boots. The files in /proc/sys can be used to fine tune and monitor miscellaneous and general things in the operation of the Linux kernel. Since some of the files @@ -1624,8 +1623,8 @@ Chapter 3: Per-process Parameters 3.1 /proc/<pid>/oom_adj & /proc/<pid>/oom_score_adj- Adjust the oom-killer score -------------------------------------------------------------------------------- -These file can be used to adjust the badness heuristic used to select which -process gets killed in out of memory conditions. +These files can be used to adjust the badness heuristic used to select which +process gets killed in out of memory (oom) conditions. The badness heuristic assigns a value to each candidate task ranging from 0 (never kill) to 1000 (always kill) to determine which process is targeted. The @@ -1681,7 +1680,7 @@ minimal amount of work. 3.2 /proc/<pid>/oom_score - Display current oom-killer score ------------------------------------------------------------- -This file can be used to check the current score used by the oom-killer is for +This file can be used to check the current score used by the oom-killer for any given <pid>. Use it together with /proc/<pid>/oom_score_adj to tune which process should be killed in an out-of-memory situation. @@ -1689,7 +1688,7 @@ process should be killed in an out-of-memory situation. 3.3 /proc/<pid>/io - Display the IO accounting fields ------------------------------------------------------- -This file contains IO statistics for each running process +This file contains IO statistics for each running process. Example ~~~~~~~ @@ -1720,7 +1719,7 @@ The number of bytes which this task has caused to be read from storage. This is simply the sum of bytes which this process passed to read() and pread(). It includes things like tty IO and it is unaffected by whether or not actual physical disk IO was required (the read might have been satisfied from -pagecache) +pagecache). wchar @@ -1878,7 +1877,7 @@ For more information on mount propagation see: 3.6 /proc/<pid>/comm & /proc/<pid>/task/<tid>/comm -------------------------------------------------------- -These files provide a method to access a tasks comm value. It also allows for +These files provide a method to access a task's comm value. It also allows for a task to set its own or one of its thread siblings comm value. The comm value is limited in size compared to the cmdline value, so writing anything longer then the kernel's TASK_COMM_LEN (currently 16 chars) will result in a truncated @@ -1891,21 +1890,21 @@ This file provides a fast way to retrieve first level children pids of a task pointed by <pid>/<tid> pair. The format is a space separated stream of pids. -Note the "first level" here -- if a child has own children they will -not be listed here, one needs to read /proc/<children-pid>/task/<tid>/children +Note the "first level" here -- if a child has its own children they will +not be listed here; one needs to read /proc/<children-pid>/task/<tid>/children to obtain the descendants. Since this interface is intended to be fast and cheap it doesn't guarantee to provide precise results and some children might be skipped, especially if they've exited right after we printed their -pids, so one need to either stop or freeze processes being inspected +pids, so one needs to either stop or freeze processes being inspected if precise results are needed. 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 three fields -- 'pos', 'flags' and mnt_id. The 'pos' +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 @@ -1976,7 +1975,7 @@ For inotify files the format is the following:: flags: 02000000 inotify wd:3 ino:9e7e sdev:800013 mask:800afce ignored_mask:0 fhandle-bytes:8 fhandle-type:1 f_handle:7e9e0000640d1b6d -where 'wd' is a watch descriptor in decimal form, ie a target file +where 'wd' is a watch descriptor in decimal form, i.e. a target file descriptor number, 'ino' and 'sdev' are inode and device where the target file resides and the 'mask' is the mask of events, all in hex form [see inotify(7) for more details]. @@ -2003,10 +2002,10 @@ For fanotify files the format is:: where fanotify 'flags' and 'event-flags' are values used in fanotify_init call, 'mnt_id' is the mount point identifier, 'mflags' is the value of flags associated with mark which are tracked separately from events -mask. 'ino', 'sdev' are target inode and device, 'mask' is the events +mask. 'ino' and 'sdev' are target inode and device, 'mask' is the events mask and 'ignored_mask' is the mask of events which are to be ignored. -All in hex format. Incorporation of 'mflags', 'mask' and 'ignored_mask' -does provide information about flags and mask used in fanotify_mark +All are in hex format. Incorporation of 'mflags', 'mask' and 'ignored_mask' +provide information about flags and mask used in fanotify_mark call [see fsnotify manpage for details]. While the first three lines are mandatory and always printed, the rest is @@ -2029,7 +2028,7 @@ Timerfd files where 'clockid' is the clock type and 'ticks' is the number of the timer expirations that have occurred [see timerfd_create(2) for details]. 'settime flags' are flags in octal form been used to setup the timer [see timerfd_settime(2) for -details]. 'it_value' is remaining time until the timer exiration. +details]. 'it_value' is remaining time until the timer expiration. 'it_interval' is the interval for the timer. Note the timer might be set up with TIMER_ABSTIME option which will be shown in 'settime flags', but 'it_value' still exhibits timer's remaining time. @@ -2059,13 +2058,13 @@ are actually shared. 3.10 /proc/<pid>/timerslack_ns - Task timerslack value --------------------------------------------------------- This file provides the value of the task's timerslack value in nanoseconds. -This value specifies a amount of time that normal timers may be deferred +This value specifies an amount of time that normal timers may be deferred in order to coalesce timers and avoid unnecessary wakeups. -This allows a task's interactivity vs power consumption trade off to be +This allows a task's interactivity vs power consumption tradeoff to be adjusted. -Writing 0 to the file will set the tasks timerslack to the default value. +Writing 0 to the file will set the task's timerslack to the default value. Valid values are from 0 - ULLONG_MAX @@ -2105,10 +2104,10 @@ Example Description ~~~~~~~~~~~ -x86 specific entries: +x86 specific entries ~~~~~~~~~~~~~~~~~~~~~ -AVX512_elapsed_ms: +AVX512_elapsed_ms ^^^^^^^^^^^^^^^^^^ If AVX512 is supported on the machine, this entry shows the milliseconds @@ -2134,8 +2133,8 @@ AVX512_elapsed_ms: the task is unlikely an AVX512 user, but depends on the workload and the scheduling scenario, it also could be a false negative mentioned above. -Configuring procfs ------------------- +Chapter 4: Configuring procfs +============================= 4.1 Mount options --------------------- @@ -2178,47 +2177,45 @@ information about processes information, just add identd to this group. subset=pid hides all top level files and directories in the procfs that are not related to tasks. -5 Filesystem behavior ----------------------------- +Chapter 5: Filesystem behavior +============================== Originally, before the advent of pid namepsace, procfs was a global file system. It means that there was only one procfs instance in the system. When pid namespace was added, a separate procfs instance was mounted in each pid namespace. So, procfs mount options are global among all -mountpoints within the same namespace. - -:: +mountpoints within the same namespace:: -# grep ^proc /proc/mounts -proc /proc proc rw,relatime,hidepid=2 0 0 + # grep ^proc /proc/mounts + proc /proc proc rw,relatime,hidepid=2 0 0 -# strace -e mount mount -o hidepid=1 -t proc proc /tmp/proc -mount("proc", "/tmp/proc", "proc", 0, "hidepid=1") = 0 -+++ exited with 0 +++ + # strace -e mount mount -o hidepid=1 -t proc proc /tmp/proc + mount("proc", "/tmp/proc", "proc", 0, "hidepid=1") = 0 + +++ exited with 0 +++ -# grep ^proc /proc/mounts -proc /proc proc rw,relatime,hidepid=2 0 0 -proc /tmp/proc proc rw,relatime,hidepid=2 0 0 + # grep ^proc /proc/mounts + proc /proc proc rw,relatime,hidepid=2 0 0 + proc /tmp/proc proc rw,relatime,hidepid=2 0 0 and only after remounting procfs mount options will change at all -mountpoints. +mountpoints:: -# mount -o remount,hidepid=1 -t proc proc /tmp/proc + # mount -o remount,hidepid=1 -t proc proc /tmp/proc -# grep ^proc /proc/mounts -proc /proc proc rw,relatime,hidepid=1 0 0 -proc /tmp/proc proc rw,relatime,hidepid=1 0 0 + # grep ^proc /proc/mounts + proc /proc proc rw,relatime,hidepid=1 0 0 + proc /tmp/proc proc rw,relatime,hidepid=1 0 0 This behavior is different from the behavior of other filesystems. The new procfs behavior is more like other filesystems. Each procfs mount creates a new procfs instance. Mount options affect own procfs instance. It means that it became possible to have several procfs instances -displaying tasks with different filtering options in one pid namespace. +displaying tasks with different filtering options in one pid namespace:: -# mount -o hidepid=invisible -t proc proc /proc -# mount -o hidepid=noaccess -t proc proc /tmp/proc -# grep ^proc /proc/mounts -proc /proc proc rw,relatime,hidepid=invisible 0 0 -proc /tmp/proc proc rw,relatime,hidepid=noaccess 0 0 + # mount -o hidepid=invisible -t proc proc /proc + # mount -o hidepid=noaccess -t proc proc /tmp/proc + # grep ^proc /proc/mounts + proc /proc proc rw,relatime,hidepid=invisible 0 0 + proc /tmp/proc proc rw,relatime,hidepid=noaccess 0 0 diff --git a/Documentation/filesystems/ramfs-rootfs-initramfs.rst b/Documentation/filesystems/ramfs-rootfs-initramfs.rst index 3fddacc6bf14..4598b0d90b60 100644 --- a/Documentation/filesystems/ramfs-rootfs-initramfs.rst +++ b/Documentation/filesystems/ramfs-rootfs-initramfs.rst @@ -246,15 +246,15 @@ If you don't already understand what shared libraries, devices, and paths you need to get a minimal root filesystem up and running, here are some references: -- http://www.tldp.org/HOWTO/Bootdisk-HOWTO/ -- http://www.tldp.org/HOWTO/From-PowerUp-To-Bash-Prompt-HOWTO.html +- https://www.tldp.org/HOWTO/Bootdisk-HOWTO/ +- https://www.tldp.org/HOWTO/From-PowerUp-To-Bash-Prompt-HOWTO.html - http://www.linuxfromscratch.org/lfs/view/stable/ -The "klibc" package (http://www.kernel.org/pub/linux/libs/klibc) is +The "klibc" package (https://www.kernel.org/pub/linux/libs/klibc) is designed to be a tiny C library to statically link early userspace code against, along with some related utilities. It is BSD licensed. -I use uClibc (http://www.uclibc.org) and busybox (http://www.busybox.net) +I use uClibc (https://www.uclibc.org) and busybox (https://www.busybox.net) myself. These are LGPL and GPL, respectively. (A self-contained initramfs package is planned for the busybox 1.3 release.) diff --git a/Documentation/filesystems/sysfs-pci.rst b/Documentation/filesystems/sysfs-pci.rst index a265f3e2cc80..742fbd21dc1f 100644 --- a/Documentation/filesystems/sysfs-pci.rst +++ b/Documentation/filesystems/sysfs-pci.rst @@ -63,7 +63,7 @@ files, each with their own function. binary - file contains binary data cpumask - file contains a cpumask type -.. [1] rw for RESOURCE_IO (I/O port) regions only +.. [1] rw for IORESOURCE_IO (I/O port) regions only The read only files are informational, writes to them will be ignored, with the exception of the 'rom' file. Writable files can be used to perform diff --git a/Documentation/filesystems/sysfs-tagging.rst b/Documentation/filesystems/sysfs-tagging.rst index 8888a05c398e..83647e10c207 100644 --- a/Documentation/filesystems/sysfs-tagging.rst +++ b/Documentation/filesystems/sysfs-tagging.rst @@ -15,7 +15,7 @@ To avoid that problem and allow existing applications in network namespaces to see the same interface that is currently presented in sysfs, sysfs now has tagging directory support. -By using the network namespace pointers as tags to separate out the +By using the network namespace pointers as tags to separate out the sysfs directory entries we ensure that we don't have conflicts in the directories and applications only see a limited set of the network devices. diff --git a/Documentation/filesystems/ubifs-authentication.rst b/Documentation/filesystems/ubifs-authentication.rst index 16efd729bf7c..1f39c8cea702 100644 --- a/Documentation/filesystems/ubifs-authentication.rst +++ b/Documentation/filesystems/ubifs-authentication.rst @@ -433,9 +433,9 @@ will then have to be provided beforehand in the normal way. References ========== -[CRYPTSETUP2] http://www.saout.de/pipermail/dm-crypt/2017-November/005745.html +[CRYPTSETUP2] https://www.saout.de/pipermail/dm-crypt/2017-November/005745.html -[DMC-CBC-ATTACK] http://www.jakoblell.com/blog/2013/12/22/practical-malleability-attack-against-cbc-encrypted-luks-partitions/ +[DMC-CBC-ATTACK] https://www.jakoblell.com/blog/2013/12/22/practical-malleability-attack-against-cbc-encrypted-luks-partitions/ [DM-INTEGRITY] https://www.kernel.org/doc/Documentation/device-mapper/dm-integrity.rst diff --git a/Documentation/filesystems/vfs.rst b/Documentation/filesystems/vfs.rst index ed17771c212b..ca52c82e5bb5 100644 --- a/Documentation/filesystems/vfs.rst +++ b/Documentation/filesystems/vfs.rst @@ -392,7 +392,7 @@ Extended attributes are name:value pairs. ``set`` Called by the VFS to set the value of a particular extended attribute. When the new value is NULL, called to remove a - particular extended attribute. This method is called by the the + particular extended attribute. This method is called by the setxattr(2) and removexattr(2) system calls. When none of the xattr handlers of a filesystem match the specified @@ -652,7 +652,7 @@ at any point after PG_Dirty is clear. Once it is known to be safe, PG_Writeback is cleared. Writeback makes use of a writeback_control structure to direct the -operations. This gives the the writepage and writepages operations some +operations. This gives the writepage and writepages operations some information about the nature of and reason for the writeback request, and the constraints under which it is being done. It is also used to return information back to the caller about the result of a writepage or @@ -766,9 +766,9 @@ cache in your filesystem. The following members are defined: ``writepages`` called by the VM to write out pages associated with the - address_space object. If wbc->sync_mode is WBC_SYNC_ALL, then + address_space object. If wbc->sync_mode is WB_SYNC_ALL, then the writeback_control will specify a range of pages that must be - written out. If it is WBC_SYNC_NONE, then a nr_to_write is + written out. If it is WB_SYNC_NONE, then a nr_to_write is given and that many pages should be written if possible. If no ->writepages is given, then mpage_writepages is used instead. This will choose pages from the address space that are tagged as @@ -1116,7 +1116,7 @@ otherwise noted. before any bytes were remapped. The remap_flags parameter accepts REMAP_FILE_* flags. If REMAP_FILE_DEDUP is set then the implementation must only remap if the requested file ranges have - identical contents. If REMAP_CAN_SHORTEN is set, the caller is + identical contents. If REMAP_FILE_CAN_SHORTEN is set, the caller is ok with the implementation shortening the request length to satisfy alignment or EOF requirements (or any other reason). @@ -1431,13 +1431,13 @@ Resources version.) Creating Linux virtual filesystems. 2002 - <http://lwn.net/Articles/13325/> + <https://lwn.net/Articles/13325/> The Linux Virtual File-system Layer by Neil Brown. 1999 <http://www.cse.unsw.edu.au/~neilb/oss/linux-commentary/vfs.html> A tour of the Linux VFS by Michael K. Johnson. 1996 - <http://www.tldp.org/LDP/khg/HyperNews/get/fs/vfstour.html> + <https://www.tldp.org/LDP/khg/HyperNews/get/fs/vfstour.html> A small trail through the Linux kernel by Andries Brouwer. 2001 - <http://www.win.tue.nl/~aeb/linux/vfs/trail.html> + <https://www.win.tue.nl/~aeb/linux/vfs/trail.html> |