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Diffstat (limited to 'Documentation/filesystems/porting.rst')
| -rw-r--r-- | Documentation/filesystems/porting.rst | 27 |
1 files changed, 26 insertions, 1 deletions
diff --git a/Documentation/filesystems/porting.rst b/Documentation/filesystems/porting.rst index 7233b04668fc..3397937ed838 100644 --- a/Documentation/filesystems/porting.rst +++ b/Documentation/filesystems/porting.rst @@ -211,7 +211,7 @@ test and set for you. e.g.:: inode = iget_locked(sb, ino); - if (inode->i_state & I_NEW) { + if (inode_state_read_once(inode) & I_NEW) { err = read_inode_from_disk(inode); if (err < 0) { iget_failed(inode); @@ -1286,6 +1286,11 @@ The vm_area_desc provides the minimum required information for a filesystem to initialise state upon memory mapping of a file-backed region, and output parameters for the file system to set this state. +In nearly all cases, this is all that is required for a filesystem. However, if +a filesystem needs to perform an operation such a pre-population of page tables, +then that action can be specified in the vm_area_desc->action field, which can +be configured using the mmap_action_*() helpers. + --- **mandatory** @@ -1309,3 +1314,23 @@ a different length, use vfs_parse_fs_qstr(fc, key, &QSTR_LEN(value, len)) instead. + +--- + +**mandatory** + +vfs_mkdir() now returns a dentry - the one returned by ->mkdir(). If +that dentry is different from the dentry passed in, including if it is +an IS_ERR() dentry pointer, the original dentry is dput(). + +When vfs_mkdir() returns an error, and so both dputs() the original +dentry and doesn't provide a replacement, it also unlocks the parent. +Consequently the return value from vfs_mkdir() can be passed to +end_creating() and the parent will be unlocked precisely when necessary. + +--- + +**mandatory** + +kill_litter_super() is gone; convert to DCACHE_PERSISTENT use (as all +in-tree filesystems have done). |