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-rw-r--r--Documentation/filesystems/vfs.txt43
1 files changed, 28 insertions, 15 deletions
diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt
index deb48b5fd88..a1d0d7a3016 100644
--- a/Documentation/filesystems/vfs.txt
+++ b/Documentation/filesystems/vfs.txt
@@ -347,6 +347,8 @@ struct inode_operations {
int (*mknod) (struct inode *,struct dentry *,umode_t,dev_t);
int (*rename) (struct inode *, struct dentry *,
struct inode *, struct dentry *);
+ 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 *);
@@ -414,6 +416,20 @@ otherwise noted.
rename: called by the rename(2) system call to rename the object to
have the parent and name given by the second inode and dentry.
+ rename2: this has an additional flags argument compared to rename.
+ If no flags are supported by the filesystem then this method
+ need not be implemented. If some flags are supported then the
+ filesystem must return -EINVAL for any unsupported or unknown
+ flags. Currently the following flags are implemented:
+ (1) RENAME_NOREPLACE: this flag indicates that if the target
+ of the rename exists the rename should fail with -EEXIST
+ instead of replacing the target. The VFS already checks for
+ existence, so for local filesystems the RENAME_NOREPLACE
+ implementation is equivalent to plain rename.
+ (2) RENAME_EXCHANGE: exchange source and target. Both must
+ exist; this is checked by the VFS. Unlike plain rename,
+ source and target may be of different type.
+
readlink: called by the readlink(2) system call. Only required if
you want to support reading symbolic links
@@ -573,14 +589,13 @@ 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 *, const struct iovec *iov,
- loff_t offset, unsigned long nr_segs);
+ ssize_t (*direct_IO)(int, struct kiocb *, struct iov_iter *iter, loff_t offset);
struct page* (*get_xip_page)(struct address_space *, sector_t,
int);
/* migrate the contents of a page to the specified target */
int (*migratepage) (struct page *, struct page *);
int (*launder_page) (struct page *);
- int (*is_partially_uptodate) (struct page *, read_descriptor_t *,
+ int (*is_partially_uptodate) (struct page *, unsigned long,
unsigned long);
void (*is_dirty_writeback) (struct page *, bool *, bool *);
int (*error_remove_page) (struct mapping *mapping, struct page *page);
@@ -782,7 +797,7 @@ struct file_operations
----------------------
This describes how the VFS can manipulate an open file. As of kernel
-3.5, the following members are defined:
+3.12, the following members are defined:
struct file_operations {
struct module *owner;
@@ -791,6 +806,8 @@ struct file_operations {
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 *);
unsigned int (*poll) (struct file *, struct poll_table_struct *);
long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
@@ -803,9 +820,6 @@ struct file_operations {
int (*aio_fsync) (struct kiocb *, int datasync);
int (*fasync) (int, struct file *, int);
int (*lock) (struct file *, int, struct file_lock *);
- ssize_t (*readv) (struct file *, const struct iovec *, unsigned long, loff_t *);
- ssize_t (*writev) (struct file *, const struct iovec *, unsigned long, loff_t *);
- ssize_t (*sendfile) (struct file *, loff_t *, size_t, read_actor_t, void *);
ssize_t (*sendpage) (struct file *, struct page *, int, size_t, loff_t *, int);
unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
int (*check_flags)(int);
@@ -814,6 +828,7 @@ struct file_operations {
ssize_t (*splice_read)(struct file *, struct pipe_inode_info *, size_t, unsigned int);
int (*setlease)(struct file *, long arg, struct file_lock **);
long (*fallocate)(struct file *, int mode, loff_t offset, loff_t len);
+ int (*show_fdinfo)(struct seq_file *m, struct file *f);
};
Again, all methods are called without any locks being held, unless
@@ -823,11 +838,15 @@ otherwise noted.
read: called by read(2) and related system calls
- aio_read: called by io_submit(2) and other asynchronous I/O operations
+ 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: called by io_submit(2) and other asynchronous I/O operations
+ 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
@@ -864,12 +883,6 @@ otherwise noted.
lock: called by the fcntl(2) system call for F_GETLK, F_SETLK, and F_SETLKW
commands
- readv: called by the readv(2) system call
-
- writev: called by the writev(2) system call
-
- sendfile: called by the sendfile(2) system call
-
get_unmapped_area: called by the mmap(2) system call
check_flags: called by the fcntl(2) system call for F_SETFL command