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author | Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2015-07-20 19:08:17 +0200 |
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committer | Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2015-07-20 19:08:17 +0200 |
commit | c57d5621d2f2dc238f4b9c4d00b2a54187a75445 (patch) | |
tree | ece13738a44545fb110e5d73adbf2625bc7a1ea6 /Documentation/filesystems/vfs.txt | |
parent | Input: elan_i2c - enable ELAN0600 acpi panels (diff) | |
parent | Linux 4.2-rc3 (diff) | |
download | linux-c57d5621d2f2dc238f4b9c4d00b2a54187a75445.tar.xz linux-c57d5621d2f2dc238f4b9c4d00b2a54187a75445.zip |
Merge tag 'v4.2-rc3' into next
Sync up with Linux 4.2-rc3 to bring in infrastructure (OF) pieces.
Diffstat (limited to 'Documentation/filesystems/vfs.txt')
-rw-r--r-- | Documentation/filesystems/vfs.txt | 47 |
1 files changed, 24 insertions, 23 deletions
diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt index 966b22829f3b..5eb8456fc41e 100644 --- a/Documentation/filesystems/vfs.txt +++ b/Documentation/filesystems/vfs.txt @@ -350,8 +350,8 @@ struct inode_operations { int (*rename2) (struct inode *, struct dentry *, struct inode *, struct dentry *, unsigned int); int (*readlink) (struct dentry *, char __user *,int); - void * (*follow_link) (struct dentry *, struct nameidata *); - void (*put_link) (struct dentry *, struct nameidata *, void *); + const char *(*follow_link) (struct dentry *, void **); + void (*put_link) (struct inode *, void *); int (*permission) (struct inode *, int); int (*get_acl)(struct inode *, int); int (*setattr) (struct dentry *, struct iattr *); @@ -436,16 +436,18 @@ otherwise noted. follow_link: called by the VFS to follow a symbolic link to the inode it points to. Only required if you want to support - symbolic links. This method returns a void pointer cookie - that is passed to put_link(). + symbolic links. This method returns the symlink body + to traverse (and possibly resets the current position with + nd_jump_link()). If the body won't go away until the inode + is gone, nothing else is needed; if it needs to be otherwise + pinned, the data needed to release whatever we'd grabbed + is to be stored in void * variable passed by address to + follow_link() instance. put_link: called by the VFS to release resources allocated by - follow_link(). The cookie returned by follow_link() is passed - to this method as the last parameter. It is used by - filesystems such as NFS where page cache is not stable - (i.e. page that was installed when the symbolic link walk - started might not be in the page cache at the end of the - walk). + follow_link(). The cookie stored by follow_link() is passed + to this method as the last parameter; only called when + cookie isn't NULL. permission: called by the VFS to check for access rights on a POSIX-like filesystem. @@ -590,7 +592,7 @@ struct address_space_operations { void (*invalidatepage) (struct page *, unsigned int, unsigned int); int (*releasepage) (struct page *, int); void (*freepage)(struct page *); - ssize_t (*direct_IO)(int, struct kiocb *, struct iov_iter *iter, loff_t offset); + ssize_t (*direct_IO)(struct kiocb *, struct iov_iter *iter, loff_t offset); /* migrate the contents of a page to the specified target */ int (*migratepage) (struct page *, struct page *); int (*launder_page) (struct page *); @@ -797,15 +799,13 @@ struct file_operations ---------------------- This describes how the VFS can manipulate an open file. As of kernel -3.12, the following members are defined: +4.1, the following members are defined: struct file_operations { struct module *owner; loff_t (*llseek) (struct file *, loff_t, int); ssize_t (*read) (struct file *, char __user *, size_t, loff_t *); ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *); - ssize_t (*aio_read) (struct kiocb *, const struct iovec *, unsigned long, loff_t); - ssize_t (*aio_write) (struct kiocb *, const struct iovec *, unsigned long, loff_t); ssize_t (*read_iter) (struct kiocb *, struct iov_iter *); ssize_t (*write_iter) (struct kiocb *, struct iov_iter *); int (*iterate) (struct file *, struct dir_context *); @@ -813,8 +813,9 @@ struct file_operations { long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long); long (*compat_ioctl) (struct file *, unsigned int, unsigned long); int (*mmap) (struct file *, struct vm_area_struct *); + int (*mremap)(struct file *, struct vm_area_struct *); int (*open) (struct inode *, struct file *); - int (*flush) (struct file *); + int (*flush) (struct file *, fl_owner_t id); int (*release) (struct inode *, struct file *); int (*fsync) (struct file *, loff_t, loff_t, int datasync); int (*aio_fsync) (struct kiocb *, int datasync); @@ -824,11 +825,15 @@ struct file_operations { unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long); int (*check_flags)(int); int (*flock) (struct file *, int, struct file_lock *); - ssize_t (*splice_write)(struct pipe_inode_info *, struct file *, size_t, unsigned int); - ssize_t (*splice_read)(struct file *, struct pipe_inode_info *, size_t, unsigned int); - int (*setlease)(struct file *, long arg, struct file_lock **, void **); - long (*fallocate)(struct file *, int mode, loff_t offset, loff_t len); + ssize_t (*splice_write)(struct pipe_inode_info *, struct file *, loff_t *, size_t, unsigned int); + ssize_t (*splice_read)(struct file *, loff_t *, struct pipe_inode_info *, size_t, unsigned int); + int (*setlease)(struct file *, long, struct file_lock **, void **); + long (*fallocate)(struct file *file, int mode, loff_t offset, + loff_t len); void (*show_fdinfo)(struct seq_file *m, struct file *f); +#ifndef CONFIG_MMU + unsigned (*mmap_capabilities)(struct file *); +#endif }; Again, all methods are called without any locks being held, unless @@ -838,14 +843,10 @@ otherwise noted. read: called by read(2) and related system calls - aio_read: vectored, possibly asynchronous read - read_iter: possibly asynchronous read with iov_iter as destination write: called by write(2) and related system calls - aio_write: vectored, possibly asynchronous write - write_iter: possibly asynchronous write with iov_iter as source iterate: called when the VFS needs to read the directory contents |