[PATCH 09/13] docs: filesystems: vfs: Add code-block and txt->RST
From: Tobin C. Harding
Date: Wed Mar 13 2019 - 00:11:09 EST
Use code-block for C source code. With this in place we can rename the
.txt file to .rst. This introduces a few warnings that will be fixed
in proceeding patches.
Add '.. code-block:: c' to C source code snippets. Rename the file to
use rst file suffix.
Signed-off-by: Tobin C. Harding <tobin@xxxxxxxxxx>
---
Documentation/filesystems/index.rst | 1 +
.../filesystems/{vfs.txt => vfs.rst} | 319 +++++++++---------
2 files changed, 168 insertions(+), 152 deletions(-)
rename Documentation/filesystems/{vfs.txt => vfs.rst} (86%)
diff --git a/Documentation/filesystems/index.rst b/Documentation/filesystems/index.rst
index 1131c34d77f6..35644840a690 100644
--- a/Documentation/filesystems/index.rst
+++ b/Documentation/filesystems/index.rst
@@ -16,6 +16,7 @@ algorithms work.
.. toctree::
:maxdepth: 2
+ vfs
path-lookup.rst
api-summary
splice
diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.rst
similarity index 86%
rename from Documentation/filesystems/vfs.txt
rename to Documentation/filesystems/vfs.rst
index f52c42fc2448..84c1dfef7838 100644
--- a/Documentation/filesystems/vfs.txt
+++ b/Documentation/filesystems/vfs.rst
@@ -87,6 +87,8 @@ Registering and Mounting a Filesystem
To register and unregister a filesystem, use the following API
functions:
+.. code-block:: c
+
#include <linux/fs.h>
extern int register_filesystem(struct file_system_type *);
@@ -110,18 +112,19 @@ struct file_system_type
This describes the filesystem. As of kernel 2.6.39, the following
members are defined:
-struct file_system_type {
- const char *name;
- int fs_flags;
- struct dentry *(*mount) (struct file_system_type *, int,
- const char *, void *);
- void (*kill_sb) (struct super_block *);
- struct module *owner;
- struct file_system_type * next;
- struct list_head fs_supers;
- struct lock_class_key s_lock_key;
- struct lock_class_key s_umount_key;
-};
+.. code-block:: c
+
+ struct file_system_type {
+ const char *name;
+ int fs_flags;
+ struct dentry *(*mount) (struct file_system_type *, int, const char *, void *);
+ void (*kill_sb) (struct super_block *);
+ struct module *owner;
+ struct file_system_type * next;
+ struct list_head fs_supers;
+ struct lock_class_key s_lock_key;
+ struct lock_class_key s_umount_key;
+ };
- name: the name of the filesystem type, such as "ext2", "iso9660",
"msdos" and so on
@@ -206,30 +209,31 @@ struct super_operations
This describes how the VFS can manipulate the superblock of your
filesystem. As of kernel 2.6.22, the following members are defined:
-struct super_operations {
- struct inode *(*alloc_inode)(struct super_block *sb);
- void (*destroy_inode)(struct inode *);
-
- void (*dirty_inode) (struct inode *, int flags);
- int (*write_inode) (struct inode *, int);
- void (*drop_inode) (struct inode *);
- void (*delete_inode) (struct inode *);
- void (*put_super) (struct super_block *);
- int (*sync_fs)(struct super_block *sb, int wait);
- int (*freeze_fs) (struct super_block *);
- int (*unfreeze_fs) (struct super_block *);
- int (*statfs) (struct dentry *, struct kstatfs *);
- int (*remount_fs) (struct super_block *, int *, char *);
- void (*clear_inode) (struct inode *);
- void (*umount_begin) (struct super_block *);
-
- int (*show_options)(struct seq_file *, struct dentry *);
-
- ssize_t (*quota_read)(struct super_block *, int, char *, size_t, loff_t);
- ssize_t (*quota_write)(struct super_block *, int, const char *, size_t, loff_t);
- int (*nr_cached_objects)(struct super_block *);
- void (*free_cached_objects)(struct super_block *, int);
-};
+.. code-block:: c
+
+ struct super_operations {
+ struct inode *(*alloc_inode)(struct super_block *sb);
+ void (*destroy_inode)(struct inode *);
+ void (*dirty_inode) (struct inode *, int flags);
+ int (*write_inode) (struct inode *, int);
+ void (*drop_inode) (struct inode *);
+ void (*delete_inode) (struct inode *);
+ void (*put_super) (struct super_block *);
+ int (*sync_fs)(struct super_block *sb, int wait);
+ int (*freeze_fs) (struct super_block *);
+ int (*unfreeze_fs) (struct super_block *);
+ int (*statfs) (struct dentry *, struct kstatfs *);
+ int (*remount_fs) (struct super_block *, int *, char *);
+ void (*clear_inode) (struct inode *);
+ void (*umount_begin) (struct super_block *);
+
+ int (*show_options)(struct seq_file *, struct dentry *);
+
+ ssize_t (*quota_read)(struct super_block *, int, char *, size_t, loff_t);
+ ssize_t (*quota_write)(struct super_block *, int, const char *, size_t, loff_t);
+ int (*nr_cached_objects)(struct super_block *);
+ void (*free_cached_objects)(struct super_block *, int);
+ };
All methods are called without any locks being held, unless otherwise
noted. This means that most methods can block safely. All methods are
@@ -365,30 +369,32 @@ struct inode_operations
This describes how the VFS can manipulate an inode in your filesystem.
As of kernel 2.6.22, the following members are defined:
-struct inode_operations {
- int (*create) (struct inode *,struct dentry *, umode_t, bool);
- struct dentry * (*lookup) (struct inode *,struct dentry *, unsigned int);
- int (*link) (struct dentry *,struct inode *,struct dentry *);
- int (*unlink) (struct inode *,struct dentry *);
- int (*symlink) (struct inode *,struct dentry *,const char *);
- int (*mkdir) (struct inode *,struct dentry *,umode_t);
- int (*rmdir) (struct inode *,struct dentry *);
- int (*mknod) (struct inode *,struct dentry *,umode_t,dev_t);
- int (*rename) (struct inode *, struct dentry *,
- struct inode *, struct dentry *, unsigned int);
- int (*readlink) (struct dentry *, char __user *,int);
- const char *(*get_link) (struct dentry *, struct inode *,
- struct delayed_call *);
- int (*permission) (struct inode *, int);
- int (*get_acl)(struct inode *, int);
- int (*setattr) (struct dentry *, struct iattr *);
- int (*getattr) (const struct path *, struct kstat *, u32, unsigned int);
- ssize_t (*listxattr) (struct dentry *, char *, size_t);
- void (*update_time)(struct inode *, struct timespec *, int);
- int (*atomic_open)(struct inode *, struct dentry *, struct file *,
- unsigned open_flag, umode_t create_mode);
- int (*tmpfile) (struct inode *, struct dentry *, umode_t);
-};
+.. code-block:: c
+
+ struct inode_operations {
+ int (*create) (struct inode *,struct dentry *, umode_t, bool);
+ struct dentry * (*lookup) (struct inode *,struct dentry *, unsigned int);
+ int (*link) (struct dentry *,struct inode *,struct dentry *);
+ int (*unlink) (struct inode *,struct dentry *);
+ int (*symlink) (struct inode *,struct dentry *,const char *);
+ int (*mkdir) (struct inode *,struct dentry *,umode_t);
+ int (*rmdir) (struct inode *,struct dentry *);
+ int (*mknod) (struct inode *,struct dentry *,umode_t,dev_t);
+ int (*rename) (struct inode *, struct dentry *,
+ struct inode *, struct dentry *, unsigned int);
+ int (*readlink) (struct dentry *, char __user *,int);
+ const char *(*get_link) (struct dentry *, struct inode *,
+ struct delayed_call *);
+ int (*permission) (struct inode *, int);
+ int (*get_acl)(struct inode *, int);
+ int (*setattr) (struct dentry *, struct iattr *);
+ int (*getattr) (const struct path *, struct kstat *, u32, unsigned int);
+ ssize_t (*listxattr) (struct dentry *, char *, size_t);
+ void (*update_time)(struct inode *, struct timespec *, int);
+ int (*atomic_open)(struct inode *, struct dentry *, struct file *,
+ unsigned open_flag, umode_t create_mode);
+ int (*tmpfile) (struct inode *, struct dentry *, umode_t);
+ };
Again, all methods are called without any locks being held, unless
otherwise noted.
@@ -624,39 +630,41 @@ struct address_space_operations
This describes how the VFS can manipulate mapping of a file to page
cache in your filesystem. The following members are defined:
-struct address_space_operations {
- int (*writepage)(struct page *page, struct writeback_control *wbc);
- int (*readpage)(struct file *, struct page *);
- int (*writepages)(struct address_space *, struct writeback_control *);
- int (*set_page_dirty)(struct page *page);
- int (*readpages)(struct file *filp, struct address_space *mapping,
- struct list_head *pages, unsigned nr_pages);
- int (*write_begin)(struct file *, struct address_space *mapping,
- loff_t pos, unsigned len, unsigned flags,
- struct page **pagep, void **fsdata);
- int (*write_end)(struct file *, struct address_space *mapping,
- loff_t pos, unsigned len, unsigned copied,
- struct page *page, void *fsdata);
- sector_t (*bmap)(struct address_space *, sector_t);
- void (*invalidatepage) (struct page *, unsigned int, unsigned int);
- int (*releasepage) (struct page *, int);
- void (*freepage)(struct page *);
- ssize_t (*direct_IO)(struct kiocb *, struct iov_iter *iter);
- /* isolate a page for migration */
- bool (*isolate_page) (struct page *, isolate_mode_t);
- /* migrate the contents of a page to the specified target */
- int (*migratepage) (struct page *, struct page *);
- /* put migration-failed page back to right list */
- void (*putback_page) (struct page *);
- int (*launder_page) (struct page *);
-
- 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);
- int (*swap_activate)(struct file *);
- int (*swap_deactivate)(struct file *);
-};
+.. code-block:: c
+
+ struct address_space_operations {
+ int (*writepage)(struct page *page, struct writeback_control *wbc);
+ int (*readpage)(struct file *, struct page *);
+ int (*writepages)(struct address_space *, struct writeback_control *);
+ int (*set_page_dirty)(struct page *page);
+ int (*readpages)(struct file *filp, struct address_space *mapping,
+ struct list_head *pages, unsigned nr_pages);
+ int (*write_begin)(struct file *, struct address_space *mapping,
+ loff_t pos, unsigned len, unsigned flags,
+ struct page **pagep, void **fsdata);
+ int (*write_end)(struct file *, struct address_space *mapping,
+ loff_t pos, unsigned len, unsigned copied,
+ struct page *page, void *fsdata);
+ sector_t (*bmap)(struct address_space *, sector_t);
+ void (*invalidatepage) (struct page *, unsigned int, unsigned int);
+ int (*releasepage) (struct page *, int);
+ void (*freepage)(struct page *);
+ ssize_t (*direct_IO)(struct kiocb *, struct iov_iter *iter);
+ /* isolate a page for migration */
+ bool (*isolate_page) (struct page *, isolate_mode_t);
+ /* migrate the contents of a page to the specified target */
+ int (*migratepage) (struct page *, struct page *);
+ /* put migration-failed page back to right list */
+ void (*putback_page) (struct page *);
+ int (*launder_page) (struct page *);
+
+ 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);
+ int (*swap_activate)(struct file *);
+ int (*swap_deactivate)(struct file *);
+ };
- writepage: called by the VM to write a dirty page to backing store.
This may happen for data integrity reasons (i.e. 'sync'), or
@@ -852,44 +860,49 @@ struct file_operations
This describes how the VFS can manipulate an open file. As of kernel
4.18, 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 (*read_iter) (struct kiocb *, struct iov_iter *);
- ssize_t (*write_iter) (struct kiocb *, struct iov_iter *);
- int (*iterate) (struct file *, struct dir_context *);
- int (*iterate_shared) (struct file *, struct dir_context *);
- __poll_t (*poll) (struct file *, struct poll_table_struct *);
- 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 (*open) (struct inode *, 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 (*fasync) (int, struct file *, int);
- int (*lock) (struct file *, int, struct file_lock *);
- 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);
- int (*flock) (struct file *, int, struct file_lock *);
- 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
- ssize_t (*copy_file_range)(struct file *, loff_t, struct file *, loff_t, size_t, unsigned int);
- loff_t (*remap_file_range)(struct file *file_in, loff_t pos_in,
- struct file *file_out, loff_t pos_out,
- loff_t len, unsigned int remap_flags);
- int (*fadvise)(struct file *, loff_t, loff_t, int);
-};
+.. code-block:: c
+
+ 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 (*read_iter) (struct kiocb *, struct iov_iter *);
+ ssize_t (*write_iter) (struct kiocb *, struct iov_iter *);
+ int (*iterate) (struct file *, struct dir_context *);
+ int (*iterate_shared) (struct file *, struct dir_context *);
+ __poll_t (*poll) (struct file *, struct poll_table_struct *);
+ 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 (*open) (struct inode *, 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 (*fasync) (int, struct file *, int);
+ int (*lock) (struct file *, int, struct file_lock *);
+ 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);
+ int (*flock) (struct file *, int, struct file_lock *);
+ 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
+ ssize_t (*copy_file_range)(struct file *, loff_t, struct file *, loff_t,
+ size_t, unsigned int);
+ loff_t (*remap_file_range)(struct file *file_in, loff_t pos_in,
+ struct file *file_out, loff_t pos_out,
+ loff_t len, unsigned int remap_flags);
+ int (*fadvise)(struct file *, loff_t, loff_t, int);
+ };
Again, all methods are called without any locks being held, unless
otherwise noted.
@@ -1003,21 +1016,23 @@ here. These methods may be set to NULL, as they are either optional or
the VFS uses a default. As of kernel 2.6.22, the following members are
defined:
-struct dentry_operations {
- int (*d_revalidate)(struct dentry *, unsigned int);
- int (*d_weak_revalidate)(struct dentry *, unsigned int);
- int (*d_hash)(const struct dentry *, struct qstr *);
- int (*d_compare)(const struct dentry *,
- unsigned int, const char *, const struct qstr *);
- int (*d_delete)(const struct dentry *);
- int (*d_init)(struct dentry *);
- void (*d_release)(struct dentry *);
- void (*d_iput)(struct dentry *, struct inode *);
- char *(*d_dname)(struct dentry *, char *, int);
- struct vfsmount *(*d_automount)(struct path *);
- int (*d_manage)(const struct path *, bool);
- struct dentry *(*d_real)(struct dentry *, const struct inode *);
-};
+.. code-block:: c
+
+ struct dentry_operations {
+ int (*d_revalidate)(struct dentry *, unsigned int);
+ int (*d_weak_revalidate)(struct dentry *, unsigned int);
+ int (*d_hash)(const struct dentry *, struct qstr *);
+ int (*d_compare)(const struct dentry *,
+ unsigned int, const char *, const struct qstr *);
+ int (*d_delete)(const struct dentry *);
+ int (*d_init)(struct dentry *);
+ void (*d_release)(struct dentry *);
+ void (*d_iput)(struct dentry *, struct inode *);
+ char *(*d_dname)(struct dentry *, char *, int);
+ struct vfsmount *(*d_automount)(struct path *);
+ int (*d_manage)(const struct path *, bool);
+ struct dentry *(*d_real)(struct dentry *, const struct inode *);
+ };
- d_revalidate: called when the VFS needs to revalidate a dentry. This
is called whenever a name look-up finds a dentry in the
@@ -1103,13 +1118,13 @@ struct dentry_operations {
at the end of the buffer, and returns a pointer to the first char.
dynamic_dname() helper function is provided to take care of this.
- Example :
+ .. code-block:: c
- static char *pipefs_dname(struct dentry *dent, char *buffer, int buflen)
- {
- return dynamic_dname(dentry, buffer, buflen, "pipe:[%lu]",
- dentry->d_inode->i_ino);
- }
+ static char *pipefs_dname(struct dentry *dent, char *buffer, int buflen)
+ {
+ return dynamic_dname(dentry, buffer, buflen, "pipe:[%lu]",
+ dentry->d_inode->i_ino);
+ }
- d_automount: called when an automount dentry is to be traversed (optional).
This should create a new VFS mount record and return the record to the
--
2.21.0