diff options
Diffstat (limited to 'Documentation/filesystems')
| -rw-r--r-- | Documentation/filesystems/dax.txt | 6 | ||||
| -rw-r--r-- | Documentation/filesystems/debugfs.rst | 12 | ||||
| -rw-r--r-- | Documentation/filesystems/dlmfs.rst | 2 | ||||
| -rw-r--r-- | Documentation/filesystems/ext4/verity.rst | 3 | ||||
| -rw-r--r-- | Documentation/filesystems/f2fs.rst | 12 | ||||
| -rw-r--r-- | Documentation/filesystems/fscrypt.rst | 25 | ||||
| -rw-r--r-- | Documentation/filesystems/locking.rst | 4 | ||||
| -rw-r--r-- | Documentation/filesystems/ocfs2.rst | 2 | ||||
| -rw-r--r-- | Documentation/filesystems/overlayfs.rst | 4 | ||||
| -rw-r--r-- | Documentation/filesystems/proc.rst | 11 | ||||
| -rw-r--r-- | Documentation/filesystems/quota.rst | 12 | ||||
| -rw-r--r-- | Documentation/filesystems/tmpfs.rst | 18 | ||||
| -rw-r--r-- | Documentation/filesystems/udf.rst | 2 | ||||
| -rw-r--r-- | Documentation/filesystems/zonefs.rst | 22 |
14 files changed, 90 insertions, 45 deletions
diff --git a/Documentation/filesystems/dax.txt b/Documentation/filesystems/dax.txt index 8e2670781c9b..8fdb78f3c6c9 100644 --- a/Documentation/filesystems/dax.txt +++ b/Documentation/filesystems/dax.txt @@ -25,7 +25,7 @@ size when creating the filesystem. Currently 3 filesystems support DAX: ext2, ext4 and xfs. Enabling DAX on them is different. -Enabling DAX on ext4 and ext2 +Enabling DAX on ext2 ----------------------------- When mounting the filesystem, use the "-o dax" option on the command line or @@ -33,8 +33,8 @@ add 'dax' to the options in /etc/fstab. This works to enable DAX on all files within the filesystem. It is equivalent to the '-o dax=always' behavior below. -Enabling DAX on xfs -------------------- +Enabling DAX on xfs and ext4 +---------------------------- Summary ------- diff --git a/Documentation/filesystems/debugfs.rst b/Documentation/filesystems/debugfs.rst index 1da7a4b7383d..728ab57a611a 100644 --- a/Documentation/filesystems/debugfs.rst +++ b/Documentation/filesystems/debugfs.rst @@ -185,13 +185,17 @@ byte offsets over a base for the register block. If you want to dump an u32 array in debugfs, you can create file with:: + struct debugfs_u32_array { + u32 *array; + u32 n_elements; + }; + void debugfs_create_u32_array(const char *name, umode_t mode, struct dentry *parent, - u32 *array, u32 elements); + struct debugfs_u32_array *array); -The "array" argument provides data, and the "elements" argument is -the number of elements in the array. Note: Once array is created its -size can not be changed. +The "array" argument wraps a pointer to the array's data and the number +of its elements. Note: Once array is created its size can not be changed. There is a helper function to create device related seq_file:: diff --git a/Documentation/filesystems/dlmfs.rst b/Documentation/filesystems/dlmfs.rst index 68daaa7facf9..28dd41a63be2 100644 --- a/Documentation/filesystems/dlmfs.rst +++ b/Documentation/filesystems/dlmfs.rst @@ -12,7 +12,7 @@ dlmfs is built with OCFS2 as it requires most of its infrastructure. :Project web page: http://ocfs2.wiki.kernel.org :Tools web page: https://github.com/markfasheh/ocfs2-tools -:OCFS2 mailing lists: http://oss.oracle.com/projects/ocfs2/mailman/ +:OCFS2 mailing lists: https://oss.oracle.com/projects/ocfs2/mailman/ All code copyright 2005 Oracle except when otherwise noted. diff --git a/Documentation/filesystems/ext4/verity.rst b/Documentation/filesystems/ext4/verity.rst index 3e4c0ee0e068..e99ff3fd09f7 100644 --- a/Documentation/filesystems/ext4/verity.rst +++ b/Documentation/filesystems/ext4/verity.rst @@ -39,3 +39,6 @@ is encrypted as well as the data itself. Verity files cannot have blocks allocated past the end of the verity metadata. + +Verity and DAX are not compatible and attempts to set both of these flags +on a file will fail. diff --git a/Documentation/filesystems/f2fs.rst b/Documentation/filesystems/f2fs.rst index 1e7dade24a19..ec8d99703ecb 100644 --- a/Documentation/filesystems/f2fs.rst +++ b/Documentation/filesystems/f2fs.rst @@ -258,6 +258,14 @@ compress_extension=%s Support adding specified extension, so that f2fs can enab 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. + Note that, there is one reserved special extension '*', it + can be set to enable compression for all files. +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 @@ -737,8 +745,8 @@ Compression implementation - In order to eliminate write amplification during overwrite, F2FS only support compression on write-once file, data can be compressed only when - all logical blocks in file are valid and cluster compress ratio is lower - than specified threshold. + all logical blocks in cluster contain valid data and compress ratio of + cluster data is lower than specified threshold. - To enable compression on regular inode, there are three ways: 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/locking.rst b/Documentation/filesystems/locking.rst index c40d39c04889..64f94a18d97e 100644 --- a/Documentation/filesystems/locking.rst +++ b/Documentation/filesystems/locking.rst @@ -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 diff --git a/Documentation/filesystems/ocfs2.rst b/Documentation/filesystems/ocfs2.rst index 412386bc6506..42ca9a3d4c6e 100644 --- a/Documentation/filesystems/ocfs2.rst +++ b/Documentation/filesystems/ocfs2.rst @@ -14,7 +14,7 @@ get "mount.ocfs2" and "ocfs2_hb_ctl". Project web page: http://ocfs2.wiki.kernel.org Tools git tree: https://github.com/markfasheh/ocfs2-tools -OCFS2 mailing lists: http://oss.oracle.com/projects/ocfs2/mailman/ +OCFS2 mailing lists: https://oss.oracle.com/projects/ocfs2/mailman/ All code copyright 2005 Oracle except when otherwise noted. diff --git a/Documentation/filesystems/overlayfs.rst b/Documentation/filesystems/overlayfs.rst index e569abb09aa7..8ea83a51c266 100644 --- a/Documentation/filesystems/overlayfs.rst +++ b/Documentation/filesystems/overlayfs.rst @@ -560,8 +560,8 @@ When the NFS export feature is enabled, all directory index entries are verified on mount time to check that upper file handles are not stale. This verification may cause significant overhead in some cases. -Note: the mount options index=off,nfs_export=on are conflicting and will -result in an error. +Note: the mount options index=off,nfs_export=on are conflicting for a +read-write mount and will result in an error. Testsuite diff --git a/Documentation/filesystems/proc.rst b/Documentation/filesystems/proc.rst index e024a9efffd8..533c79e8d2cd 100644 --- a/Documentation/filesystems/proc.rst +++ b/Documentation/filesystems/proc.rst @@ -1633,9 +1633,6 @@ may allocate from based on an estimation of its current memory and swap use. For example, if a task is using all allowed memory, its badness score will be 1000. If it is using half of its allowed memory, its score will be 500. -There is an additional factor included in the badness score: the current memory -and swap usage is discounted by 3% for root processes. - The amount of "allowed" memory depends on the context in which the oom killer was called. If it is due to the memory assigned to the allocating task's cpuset being exhausted, the allowed memory represents the set of mems assigned to that @@ -1671,11 +1668,6 @@ The value of /proc/<pid>/oom_score_adj may be reduced no lower than the last value set by a CAP_SYS_RESOURCE process. To reduce the value any lower requires CAP_SYS_RESOURCE. -Caveat: when a parent task is selected, the oom killer will sacrifice any first -generation children with separate address spaces instead, if possible. This -avoids servers and important system daemons from being killed and loses the -minimal amount of work. - 3.2 /proc/<pid>/oom_score - Display current oom-killer score ------------------------------------------------------------- @@ -1684,6 +1676,9 @@ 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. +Please note that the exported value includes oom_score_adj so it is +effectively in range [0,2000]. + 3.3 /proc/<pid>/io - Display the IO accounting fields ------------------------------------------------------- diff --git a/Documentation/filesystems/quota.rst b/Documentation/filesystems/quota.rst index a30cdd47c652..abd4303c546e 100644 --- a/Documentation/filesystems/quota.rst +++ b/Documentation/filesystems/quota.rst @@ -18,7 +18,7 @@ Quota limits (and amount of grace time) are set independently for each filesystem. For more details about quota design, see the documentation in quota-tools package -(http://sourceforge.net/projects/linuxquota). +(https://sourceforge.net/projects/linuxquota). Quota netlink interface ======================= @@ -31,11 +31,11 @@ the above events to userspace. There they can be captured by an application and processed accordingly. The interface uses generic netlink framework (see -http://lwn.net/Articles/208755/ and http://people.suug.ch/~tgr/libnl/ for more -details about this layer). The name of the quota generic netlink interface -is "VFS_DQUOT". Definitions of constants below are in <linux/quota.h>. -Since the quota netlink protocol is not namespace aware, quota netlink messages -are sent only in initial network namespace. +https://lwn.net/Articles/208755/ and http://www.infradead.org/~tgr/libnl/ for +more details about this layer). The name of the quota generic netlink interface +is "VFS_DQUOT". Definitions of constants below are in <linux/quota.h>. Since +the quota netlink protocol is not namespace aware, quota netlink messages are +sent only in initial network namespace. Currently, the interface supports only one message type QUOTA_NL_C_WARNING. This command is used to send a notification about any of the above mentioned diff --git a/Documentation/filesystems/tmpfs.rst b/Documentation/filesystems/tmpfs.rst index 4e95929301a5..c44f8b1d3cab 100644 --- a/Documentation/filesystems/tmpfs.rst +++ b/Documentation/filesystems/tmpfs.rst @@ -150,6 +150,22 @@ These options do not have any effect on remount. You can change these parameters with chmod(1), chown(1) and chgrp(1) on a mounted filesystem. +tmpfs has a mount option to select whether it will wrap at 32- or 64-bit inode +numbers: + +======= ======================== +inode64 Use 64-bit inode numbers +inode32 Use 32-bit inode numbers +======= ======================== + +On a 32-bit kernel, inode32 is implicit, and inode64 is refused at mount time. +On a 64-bit kernel, CONFIG_TMPFS_INODE64 sets the default. inode64 avoids the +possibility of multiple files with the same inode number on a single device; +but risks glibc failing with EOVERFLOW once 33-bit inode numbers are reached - +if a long-lived tmpfs is accessed by 32-bit applications so ancient that +opening a file larger than 2GiB fails with EINVAL. + + So 'mount -t tmpfs -o size=10G,nr_inodes=10k,mode=700 tmpfs /mytmpfs' will give you tmpfs instance on /mytmpfs which can allocate 10GB RAM/SWAP in 10240 inodes and it is only accessible by root. @@ -161,3 +177,5 @@ RAM/SWAP in 10240 inodes and it is only accessible by root. Hugh Dickins, 4 June 2007 :Updated: KOSAKI Motohiro, 16 Mar 2010 +:Updated: + Chris Down, 13 July 2020 diff --git a/Documentation/filesystems/udf.rst b/Documentation/filesystems/udf.rst index d9badbf285b2..f9489ddbb767 100644 --- a/Documentation/filesystems/udf.rst +++ b/Documentation/filesystems/udf.rst @@ -72,4 +72,4 @@ For the latest version and toolset see: Documentation on UDF and ECMA 167 is available FREE from: - http://www.osta.org/ - - http://www.ecma-international.org/ + - https://www.ecma-international.org/ diff --git a/Documentation/filesystems/zonefs.rst b/Documentation/filesystems/zonefs.rst index 71d845c6a700..6c18bc8ce332 100644 --- a/Documentation/filesystems/zonefs.rst +++ b/Documentation/filesystems/zonefs.rst @@ -110,14 +110,14 @@ contain files named "0", "1", "2", ... The file numbers also represent increasing zone start sector on the device. All read and write operations to zone files are not allowed beyond the file -maximum size, that is, beyond the zone size. Any access exceeding the zone -size is failed with the -EFBIG error. +maximum size, that is, beyond the zone capacity. Any access exceeding the zone +capacity is failed with the -EFBIG error. Creating, deleting, renaming or modifying any attribute of files and sub-directories is not allowed. The number of blocks of a file as reported by stat() and fstat() indicates the -size of the file zone, or in other words, the maximum file size. +capacity of the zone file, or in other words, the maximum file size. Conventional zone files ----------------------- @@ -156,8 +156,8 @@ all accepted. Truncating sequential zone files is allowed only down to 0, in which case, the zone is reset to rewind the file zone write pointer position to the start of -the zone, or up to the zone size, in which case the file's zone is transitioned -to the FULL state (finish zone operation). +the zone, or up to the zone capacity, in which case the file's zone is +transitioned to the FULL state (finish zone operation). Format options -------------- @@ -324,7 +324,7 @@ file size set to 0. This is necessary as the write pointer of read-only zones is defined as invalib by the ZBC and ZAC standards, making it impossible to discover the amount of data that has been written to the zone. In the case of a read-only zone discovered at run-time, as indicated in the previous section. -the size of the zone file is left unchanged from its last updated value. +The size of the zone file is left unchanged from its last updated value. Zonefs User Space Tools ======================= @@ -401,8 +401,9 @@ append-writes to the file:: # ls -l /mnt/seq/0 -rw-r----- 1 root root 0 Nov 25 13:49 /mnt/seq/0 -Since files are statically mapped to zones on the disk, the number of blocks of -a file as reported by stat() and fstat() indicates the size of the file zone:: +Since files are statically mapped to zones on the disk, the number of blocks +of a file as reported by stat() and fstat() indicates the capacity of the file +zone:: # stat /mnt/seq/0 File: /mnt/seq/0 @@ -416,5 +417,6 @@ a file as reported by stat() and fstat() indicates the size of the file zone:: The number of blocks of the file ("Blocks") in units of 512B blocks gives the maximum file size of 524288 * 512 B = 256 MB, corresponding to the device zone -size in this example. Of note is that the "IO block" field always indicates the -minimum I/O size for writes and corresponds to the device physical sector size. +capacity in this example. Of note is that the "IO block" field always +indicates the minimum I/O size for writes and corresponds to the device +physical sector size. |