Commit 17cf28af authored by Hugh Dickins's avatar Hugh Dickins Committed by Linus Torvalds
Browse files

mm/fs: remove truncate_range 



Remove vmtruncate_range(), and remove the truncate_range method from
struct inode_operations: only tmpfs ever supported it, and tmpfs has now
converted over to using the fallocate method of file_operations.

Update Documentation accordingly, adding (setlease and) fallocate lines.
And while we're in mm.h, remove duplicate declarations of shmem_lock() and
shmem_file_setup(): everyone is now using the ones in shmem_fs.h.

Based-on-patch-by: default avatarCong Wang <amwang@redhat.com>
Signed-off-by: default avatarHugh Dickins <hughd@google.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Cong Wang <amwang@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 3f31d075

Documentation/filesystems/Locking

+0 −2
Original line number Diff line number Diff line
@@ -60,7 +60,6 @@ ata *); 
	ssize_t (*getxattr) (struct dentry *, const char *, void *, size_t);

	ssize_t (*listxattr) (struct dentry *, char *, size_t);

	int (*removexattr) (struct dentry *, const char *);

	void (*truncate_range)(struct inode *, loff_t, loff_t);

	int (*fiemap)(struct inode *, struct fiemap_extent_info *, u64 start, u64 len);



locking rules:
@@ -87,7 +86,6 @@ setxattr: yes 
getxattr:	no

listxattr:	no

removexattr:	yes

truncate_range:	yes

fiemap:		no

	Additionally, ->rmdir(), ->unlink() and ->rename() have ->i_mutex on

victim.

Documentation/filesystems/vfs.txt

+8 −5
Original line number Diff line number Diff line
@@ -363,7 +363,6 @@ struct inode_operations { 
	ssize_t (*getxattr) (struct dentry *, const char *, void *, size_t);

	ssize_t (*listxattr) (struct dentry *, char *, size_t);

	int (*removexattr) (struct dentry *, const char *);

	void (*truncate_range)(struct inode *, loff_t, loff_t);

};



Again, all methods are called without any locks being held, unless
@@ -472,9 +471,6 @@ otherwise noted. 
  removexattr: called by the VFS to remove an extended attribute from

  	a file. This method is called by removexattr(2) system call.



  truncate_range: a method provided by the underlying filesystem to truncate a

  	range of blocks , i.e. punch a hole somewhere in a file.





The Address Space Object

========================
@@ -760,7 +756,7 @@ struct file_operations 
----------------------



This describes how the VFS can manipulate an open file. As of kernel

2.6.22, the following members are defined:

3.5, the following members are defined:



struct file_operations {

	struct module *owner;
@@ -790,6 +786,8 @@ struct file_operations { 
	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 **);

	long (*fallocate)(struct file *, int mode, loff_t offset, loff_t len);

};



Again, all methods are called without any locks being held, unless
@@ -858,6 +856,11 @@ otherwise noted. 
  splice_read: called by the VFS to splice data from file to a pipe. This

	       method is used by the splice(2) system call



  setlease: called by the VFS to set or release a file lock lease.

	    setlease has the file_lock_lock held and must not sleep.



  fallocate: called by the VFS to preallocate blocks or punch a hole.



Note that the file operations are implemented by the specific

filesystem in which the inode resides. When opening a device node

(character or block special) most filesystems will call special

fs/bad_inode.c

+0 −1
Original line number Diff line number Diff line
@@ -292,7 +292,6 @@ static const struct inode_operations bad_inode_ops = 
	.getxattr	= bad_inode_getxattr,

	.listxattr	= bad_inode_listxattr,

	.removexattr	= bad_inode_removexattr,

	/* truncate_range returns void */

};

include/linux/fs.h

+0 −1
Original line number Diff line number Diff line
@@ -1681,7 +1681,6 @@ struct inode_operations { 
	ssize_t (*getxattr) (struct dentry *, const char *, void *, size_t);

	ssize_t (*listxattr) (struct dentry *, char *, size_t);

	int (*removexattr) (struct dentry *, const char *);

	void (*truncate_range)(struct inode *, loff_t, loff_t);

	int (*fiemap)(struct inode *, struct fiemap_extent_info *, u64 start,

		      u64 len);

} ____cacheline_aligned;

include/linux/mm.h

+0 −4
Original line number Diff line number Diff line
@@ -871,8 +871,6 @@ extern void pagefault_out_of_memory(void); 
extern void show_free_areas(unsigned int flags);

extern bool skip_free_areas_node(unsigned int flags, int nid);



int shmem_lock(struct file *file, int lock, struct user_struct *user);

struct file *shmem_file_setup(const char *name, loff_t size, unsigned long flags);

int shmem_zero_setup(struct vm_area_struct *);



extern int can_do_mlock(void);
@@ -951,11 +949,9 @@ static inline void unmap_shared_mapping_range(struct address_space *mapping, 
extern void truncate_pagecache(struct inode *inode, loff_t old, loff_t new);

extern void truncate_setsize(struct inode *inode, loff_t newsize);

extern int vmtruncate(struct inode *inode, loff_t offset);

extern int vmtruncate_range(struct inode *inode, loff_t offset, loff_t end);

void truncate_pagecache_range(struct inode *inode, loff_t offset, loff_t end);

int truncate_inode_page(struct address_space *mapping, struct page *page);

int generic_error_remove_page(struct address_space *mapping, struct page *page);



int invalidate_inode_page(struct page *page);



#ifdef CONFIG_MMU

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