Pull vfs updates from Al Viro:
 "This the bunch that sat in -next + lock_parent() fix.  This is the
  minimal set; there's more pending stuff.
  In particular, I really hope to get acct.c fixes merged this cycle -
  we need that to deal sanely with delayed-mntput stuff.  In the next
  pile, hopefully - that series is fairly short and localized
  (kernel/acct.c, fs/super.c and fs/namespace.c).  In this pile: more
  iov_iter work.  Most of prereqs for ->splice_write with sane locking
  order are there and Kent's dio rewrite would also fit nicely on top of
  this pile"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (70 commits)
  lock_parent: don't step on stale ->d_parent of all-but-freed one
  kill generic_file_splice_write()
  ceph: switch to iter_file_splice_write()
  shmem: switch to iter_file_splice_write()
  nfs: switch to iter_splice_write_file()
  fs/splice.c: remove unneeded exports
  ocfs2: switch to iter_file_splice_write()
  ->splice_write() via ->write_iter()
  bio_vec-backed iov_iter
  optimize copy_page_{to,from}_iter()
  bury generic_file_aio_{read,write}
  lustre: get rid of messing with iovecs
  ceph: switch to ->write_iter()
  ceph_sync_direct_write: stop poking into iov_iter guts
  ceph_sync_read: stop poking into iov_iter guts
  new helper: copy_page_from_iter()
  fuse: switch to ->write_iter()
  btrfs: switch to ->write_iter()
  ocfs2: switch to ->write_iter()
  xfs: switch to ->write_iter()
  ...
		
	
			
		
			
				
	
	
		
			917 lines
		
	
	
	
		
			21 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			917 lines
		
	
	
	
		
			21 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
/*
 | 
						|
 *  linux/fs/9p/vfs_file.c
 | 
						|
 *
 | 
						|
 * This file contians vfs file ops for 9P2000.
 | 
						|
 *
 | 
						|
 *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
 | 
						|
 *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
 | 
						|
 *
 | 
						|
 *  This program is free software; you can redistribute it and/or modify
 | 
						|
 *  it under the terms of the GNU General Public License version 2
 | 
						|
 *  as published by the Free Software Foundation.
 | 
						|
 *
 | 
						|
 *  This program is distributed in the hope that it will be useful,
 | 
						|
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 | 
						|
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 | 
						|
 *  GNU General Public License for more details.
 | 
						|
 *
 | 
						|
 *  You should have received a copy of the GNU General Public License
 | 
						|
 *  along with this program; if not, write to:
 | 
						|
 *  Free Software Foundation
 | 
						|
 *  51 Franklin Street, Fifth Floor
 | 
						|
 *  Boston, MA  02111-1301  USA
 | 
						|
 *
 | 
						|
 */
 | 
						|
 | 
						|
#include <linux/module.h>
 | 
						|
#include <linux/errno.h>
 | 
						|
#include <linux/fs.h>
 | 
						|
#include <linux/sched.h>
 | 
						|
#include <linux/file.h>
 | 
						|
#include <linux/stat.h>
 | 
						|
#include <linux/string.h>
 | 
						|
#include <linux/inet.h>
 | 
						|
#include <linux/list.h>
 | 
						|
#include <linux/pagemap.h>
 | 
						|
#include <linux/utsname.h>
 | 
						|
#include <asm/uaccess.h>
 | 
						|
#include <linux/idr.h>
 | 
						|
#include <net/9p/9p.h>
 | 
						|
#include <net/9p/client.h>
 | 
						|
 | 
						|
#include "v9fs.h"
 | 
						|
#include "v9fs_vfs.h"
 | 
						|
#include "fid.h"
 | 
						|
#include "cache.h"
 | 
						|
 | 
						|
static const struct vm_operations_struct v9fs_file_vm_ops;
 | 
						|
static const struct vm_operations_struct v9fs_mmap_file_vm_ops;
 | 
						|
 | 
						|
/**
 | 
						|
 * v9fs_file_open - open a file (or directory)
 | 
						|
 * @inode: inode to be opened
 | 
						|
 * @file: file being opened
 | 
						|
 *
 | 
						|
 */
 | 
						|
 | 
						|
int v9fs_file_open(struct inode *inode, struct file *file)
 | 
						|
{
 | 
						|
	int err;
 | 
						|
	struct v9fs_inode *v9inode;
 | 
						|
	struct v9fs_session_info *v9ses;
 | 
						|
	struct p9_fid *fid;
 | 
						|
	int omode;
 | 
						|
 | 
						|
	p9_debug(P9_DEBUG_VFS, "inode: %p file: %p\n", inode, file);
 | 
						|
	v9inode = V9FS_I(inode);
 | 
						|
	v9ses = v9fs_inode2v9ses(inode);
 | 
						|
	if (v9fs_proto_dotl(v9ses))
 | 
						|
		omode = v9fs_open_to_dotl_flags(file->f_flags);
 | 
						|
	else
 | 
						|
		omode = v9fs_uflags2omode(file->f_flags,
 | 
						|
					v9fs_proto_dotu(v9ses));
 | 
						|
	fid = file->private_data;
 | 
						|
	if (!fid) {
 | 
						|
		fid = v9fs_fid_clone(file->f_path.dentry);
 | 
						|
		if (IS_ERR(fid))
 | 
						|
			return PTR_ERR(fid);
 | 
						|
 | 
						|
		err = p9_client_open(fid, omode);
 | 
						|
		if (err < 0) {
 | 
						|
			p9_client_clunk(fid);
 | 
						|
			return err;
 | 
						|
		}
 | 
						|
		if ((file->f_flags & O_APPEND) &&
 | 
						|
			(!v9fs_proto_dotu(v9ses) && !v9fs_proto_dotl(v9ses)))
 | 
						|
			generic_file_llseek(file, 0, SEEK_END);
 | 
						|
	}
 | 
						|
 | 
						|
	file->private_data = fid;
 | 
						|
	mutex_lock(&v9inode->v_mutex);
 | 
						|
	if ((v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) &&
 | 
						|
	    !v9inode->writeback_fid &&
 | 
						|
	    ((file->f_flags & O_ACCMODE) != O_RDONLY)) {
 | 
						|
		/*
 | 
						|
		 * clone a fid and add it to writeback_fid
 | 
						|
		 * we do it during open time instead of
 | 
						|
		 * page dirty time via write_begin/page_mkwrite
 | 
						|
		 * because we want write after unlink usecase
 | 
						|
		 * to work.
 | 
						|
		 */
 | 
						|
		fid = v9fs_writeback_fid(file->f_path.dentry);
 | 
						|
		if (IS_ERR(fid)) {
 | 
						|
			err = PTR_ERR(fid);
 | 
						|
			mutex_unlock(&v9inode->v_mutex);
 | 
						|
			goto out_error;
 | 
						|
		}
 | 
						|
		v9inode->writeback_fid = (void *) fid;
 | 
						|
	}
 | 
						|
	mutex_unlock(&v9inode->v_mutex);
 | 
						|
	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
 | 
						|
		v9fs_cache_inode_set_cookie(inode, file);
 | 
						|
	return 0;
 | 
						|
out_error:
 | 
						|
	p9_client_clunk(file->private_data);
 | 
						|
	file->private_data = NULL;
 | 
						|
	return err;
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * v9fs_file_lock - lock a file (or directory)
 | 
						|
 * @filp: file to be locked
 | 
						|
 * @cmd: lock command
 | 
						|
 * @fl: file lock structure
 | 
						|
 *
 | 
						|
 * Bugs: this looks like a local only lock, we should extend into 9P
 | 
						|
 *       by using open exclusive
 | 
						|
 */
 | 
						|
 | 
						|
static int v9fs_file_lock(struct file *filp, int cmd, struct file_lock *fl)
 | 
						|
{
 | 
						|
	int res = 0;
 | 
						|
	struct inode *inode = file_inode(filp);
 | 
						|
 | 
						|
	p9_debug(P9_DEBUG_VFS, "filp: %p lock: %p\n", filp, fl);
 | 
						|
 | 
						|
	/* No mandatory locks */
 | 
						|
	if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
 | 
						|
		return -ENOLCK;
 | 
						|
 | 
						|
	if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
 | 
						|
		filemap_write_and_wait(inode->i_mapping);
 | 
						|
		invalidate_mapping_pages(&inode->i_data, 0, -1);
 | 
						|
	}
 | 
						|
 | 
						|
	return res;
 | 
						|
}
 | 
						|
 | 
						|
static int v9fs_file_do_lock(struct file *filp, int cmd, struct file_lock *fl)
 | 
						|
{
 | 
						|
	struct p9_flock flock;
 | 
						|
	struct p9_fid *fid;
 | 
						|
	uint8_t status;
 | 
						|
	int res = 0;
 | 
						|
	unsigned char fl_type;
 | 
						|
 | 
						|
	fid = filp->private_data;
 | 
						|
	BUG_ON(fid == NULL);
 | 
						|
 | 
						|
	if ((fl->fl_flags & FL_POSIX) != FL_POSIX)
 | 
						|
		BUG();
 | 
						|
 | 
						|
	res = posix_lock_file_wait(filp, fl);
 | 
						|
	if (res < 0)
 | 
						|
		goto out;
 | 
						|
 | 
						|
	/* convert posix lock to p9 tlock args */
 | 
						|
	memset(&flock, 0, sizeof(flock));
 | 
						|
	/* map the lock type */
 | 
						|
	switch (fl->fl_type) {
 | 
						|
	case F_RDLCK:
 | 
						|
		flock.type = P9_LOCK_TYPE_RDLCK;
 | 
						|
		break;
 | 
						|
	case F_WRLCK:
 | 
						|
		flock.type = P9_LOCK_TYPE_WRLCK;
 | 
						|
		break;
 | 
						|
	case F_UNLCK:
 | 
						|
		flock.type = P9_LOCK_TYPE_UNLCK;
 | 
						|
		break;
 | 
						|
	}
 | 
						|
	flock.start = fl->fl_start;
 | 
						|
	if (fl->fl_end == OFFSET_MAX)
 | 
						|
		flock.length = 0;
 | 
						|
	else
 | 
						|
		flock.length = fl->fl_end - fl->fl_start + 1;
 | 
						|
	flock.proc_id = fl->fl_pid;
 | 
						|
	flock.client_id = fid->clnt->name;
 | 
						|
	if (IS_SETLKW(cmd))
 | 
						|
		flock.flags = P9_LOCK_FLAGS_BLOCK;
 | 
						|
 | 
						|
	/*
 | 
						|
	 * if its a blocked request and we get P9_LOCK_BLOCKED as the status
 | 
						|
	 * for lock request, keep on trying
 | 
						|
	 */
 | 
						|
	for (;;) {
 | 
						|
		res = p9_client_lock_dotl(fid, &flock, &status);
 | 
						|
		if (res < 0)
 | 
						|
			break;
 | 
						|
 | 
						|
		if (status != P9_LOCK_BLOCKED)
 | 
						|
			break;
 | 
						|
		if (status == P9_LOCK_BLOCKED && !IS_SETLKW(cmd))
 | 
						|
			break;
 | 
						|
		if (schedule_timeout_interruptible(P9_LOCK_TIMEOUT) != 0)
 | 
						|
			break;
 | 
						|
	}
 | 
						|
 | 
						|
	/* map 9p status to VFS status */
 | 
						|
	switch (status) {
 | 
						|
	case P9_LOCK_SUCCESS:
 | 
						|
		res = 0;
 | 
						|
		break;
 | 
						|
	case P9_LOCK_BLOCKED:
 | 
						|
		res = -EAGAIN;
 | 
						|
		break;
 | 
						|
	case P9_LOCK_ERROR:
 | 
						|
	case P9_LOCK_GRACE:
 | 
						|
		res = -ENOLCK;
 | 
						|
		break;
 | 
						|
	default:
 | 
						|
		BUG();
 | 
						|
	}
 | 
						|
 | 
						|
	/*
 | 
						|
	 * incase server returned error for lock request, revert
 | 
						|
	 * it locally
 | 
						|
	 */
 | 
						|
	if (res < 0 && fl->fl_type != F_UNLCK) {
 | 
						|
		fl_type = fl->fl_type;
 | 
						|
		fl->fl_type = F_UNLCK;
 | 
						|
		res = posix_lock_file_wait(filp, fl);
 | 
						|
		fl->fl_type = fl_type;
 | 
						|
	}
 | 
						|
out:
 | 
						|
	return res;
 | 
						|
}
 | 
						|
 | 
						|
static int v9fs_file_getlock(struct file *filp, struct file_lock *fl)
 | 
						|
{
 | 
						|
	struct p9_getlock glock;
 | 
						|
	struct p9_fid *fid;
 | 
						|
	int res = 0;
 | 
						|
 | 
						|
	fid = filp->private_data;
 | 
						|
	BUG_ON(fid == NULL);
 | 
						|
 | 
						|
	posix_test_lock(filp, fl);
 | 
						|
	/*
 | 
						|
	 * if we have a conflicting lock locally, no need to validate
 | 
						|
	 * with server
 | 
						|
	 */
 | 
						|
	if (fl->fl_type != F_UNLCK)
 | 
						|
		return res;
 | 
						|
 | 
						|
	/* convert posix lock to p9 tgetlock args */
 | 
						|
	memset(&glock, 0, sizeof(glock));
 | 
						|
	glock.type  = P9_LOCK_TYPE_UNLCK;
 | 
						|
	glock.start = fl->fl_start;
 | 
						|
	if (fl->fl_end == OFFSET_MAX)
 | 
						|
		glock.length = 0;
 | 
						|
	else
 | 
						|
		glock.length = fl->fl_end - fl->fl_start + 1;
 | 
						|
	glock.proc_id = fl->fl_pid;
 | 
						|
	glock.client_id = fid->clnt->name;
 | 
						|
 | 
						|
	res = p9_client_getlock_dotl(fid, &glock);
 | 
						|
	if (res < 0)
 | 
						|
		return res;
 | 
						|
	/* map 9p lock type to os lock type */
 | 
						|
	switch (glock.type) {
 | 
						|
	case P9_LOCK_TYPE_RDLCK:
 | 
						|
		fl->fl_type = F_RDLCK;
 | 
						|
		break;
 | 
						|
	case P9_LOCK_TYPE_WRLCK:
 | 
						|
		fl->fl_type = F_WRLCK;
 | 
						|
		break;
 | 
						|
	case P9_LOCK_TYPE_UNLCK:
 | 
						|
		fl->fl_type = F_UNLCK;
 | 
						|
		break;
 | 
						|
	}
 | 
						|
	if (glock.type != P9_LOCK_TYPE_UNLCK) {
 | 
						|
		fl->fl_start = glock.start;
 | 
						|
		if (glock.length == 0)
 | 
						|
			fl->fl_end = OFFSET_MAX;
 | 
						|
		else
 | 
						|
			fl->fl_end = glock.start + glock.length - 1;
 | 
						|
		fl->fl_pid = glock.proc_id;
 | 
						|
	}
 | 
						|
	return res;
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * v9fs_file_lock_dotl - lock a file (or directory)
 | 
						|
 * @filp: file to be locked
 | 
						|
 * @cmd: lock command
 | 
						|
 * @fl: file lock structure
 | 
						|
 *
 | 
						|
 */
 | 
						|
 | 
						|
static int v9fs_file_lock_dotl(struct file *filp, int cmd, struct file_lock *fl)
 | 
						|
{
 | 
						|
	struct inode *inode = file_inode(filp);
 | 
						|
	int ret = -ENOLCK;
 | 
						|
 | 
						|
	p9_debug(P9_DEBUG_VFS, "filp: %p cmd:%d lock: %p name: %s\n",
 | 
						|
		 filp, cmd, fl, filp->f_path.dentry->d_name.name);
 | 
						|
 | 
						|
	/* No mandatory locks */
 | 
						|
	if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
 | 
						|
		goto out_err;
 | 
						|
 | 
						|
	if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
 | 
						|
		filemap_write_and_wait(inode->i_mapping);
 | 
						|
		invalidate_mapping_pages(&inode->i_data, 0, -1);
 | 
						|
	}
 | 
						|
 | 
						|
	if (IS_SETLK(cmd) || IS_SETLKW(cmd))
 | 
						|
		ret = v9fs_file_do_lock(filp, cmd, fl);
 | 
						|
	else if (IS_GETLK(cmd))
 | 
						|
		ret = v9fs_file_getlock(filp, fl);
 | 
						|
	else
 | 
						|
		ret = -EINVAL;
 | 
						|
out_err:
 | 
						|
	return ret;
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * v9fs_file_flock_dotl - lock a file
 | 
						|
 * @filp: file to be locked
 | 
						|
 * @cmd: lock command
 | 
						|
 * @fl: file lock structure
 | 
						|
 *
 | 
						|
 */
 | 
						|
 | 
						|
static int v9fs_file_flock_dotl(struct file *filp, int cmd,
 | 
						|
	struct file_lock *fl)
 | 
						|
{
 | 
						|
	struct inode *inode = file_inode(filp);
 | 
						|
	int ret = -ENOLCK;
 | 
						|
 | 
						|
	p9_debug(P9_DEBUG_VFS, "filp: %p cmd:%d lock: %p name: %s\n",
 | 
						|
		 filp, cmd, fl, filp->f_path.dentry->d_name.name);
 | 
						|
 | 
						|
	/* No mandatory locks */
 | 
						|
	if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
 | 
						|
		goto out_err;
 | 
						|
 | 
						|
	if (!(fl->fl_flags & FL_FLOCK))
 | 
						|
		goto out_err;
 | 
						|
 | 
						|
	if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
 | 
						|
		filemap_write_and_wait(inode->i_mapping);
 | 
						|
		invalidate_mapping_pages(&inode->i_data, 0, -1);
 | 
						|
	}
 | 
						|
	/* Convert flock to posix lock */
 | 
						|
	fl->fl_flags |= FL_POSIX;
 | 
						|
	fl->fl_flags ^= FL_FLOCK;
 | 
						|
 | 
						|
	if (IS_SETLK(cmd) | IS_SETLKW(cmd))
 | 
						|
		ret = v9fs_file_do_lock(filp, cmd, fl);
 | 
						|
	else
 | 
						|
		ret = -EINVAL;
 | 
						|
out_err:
 | 
						|
	return ret;
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * v9fs_fid_readn - read from a fid
 | 
						|
 * @fid: fid to read
 | 
						|
 * @data: data buffer to read data into
 | 
						|
 * @udata: user data buffer to read data into
 | 
						|
 * @count: size of buffer
 | 
						|
 * @offset: offset at which to read data
 | 
						|
 *
 | 
						|
 */
 | 
						|
ssize_t
 | 
						|
v9fs_fid_readn(struct p9_fid *fid, char *data, char __user *udata, u32 count,
 | 
						|
	       u64 offset)
 | 
						|
{
 | 
						|
	int n, total, size;
 | 
						|
 | 
						|
	p9_debug(P9_DEBUG_VFS, "fid %d offset %llu count %d\n",
 | 
						|
		 fid->fid, (long long unsigned)offset, count);
 | 
						|
	n = 0;
 | 
						|
	total = 0;
 | 
						|
	size = fid->iounit ? fid->iounit : fid->clnt->msize - P9_IOHDRSZ;
 | 
						|
	do {
 | 
						|
		n = p9_client_read(fid, data, udata, offset, count);
 | 
						|
		if (n <= 0)
 | 
						|
			break;
 | 
						|
 | 
						|
		if (data)
 | 
						|
			data += n;
 | 
						|
		if (udata)
 | 
						|
			udata += n;
 | 
						|
 | 
						|
		offset += n;
 | 
						|
		count -= n;
 | 
						|
		total += n;
 | 
						|
	} while (count > 0 && n == size);
 | 
						|
 | 
						|
	if (n < 0)
 | 
						|
		total = n;
 | 
						|
 | 
						|
	return total;
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * v9fs_file_readn - read from a file
 | 
						|
 * @filp: file pointer to read
 | 
						|
 * @data: data buffer to read data into
 | 
						|
 * @udata: user data buffer to read data into
 | 
						|
 * @count: size of buffer
 | 
						|
 * @offset: offset at which to read data
 | 
						|
 *
 | 
						|
 */
 | 
						|
ssize_t
 | 
						|
v9fs_file_readn(struct file *filp, char *data, char __user *udata, u32 count,
 | 
						|
	       u64 offset)
 | 
						|
{
 | 
						|
	return v9fs_fid_readn(filp->private_data, data, udata, count, offset);
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * v9fs_file_read - read from a file
 | 
						|
 * @filp: file pointer to read
 | 
						|
 * @udata: user data buffer to read data into
 | 
						|
 * @count: size of buffer
 | 
						|
 * @offset: offset at which to read data
 | 
						|
 *
 | 
						|
 */
 | 
						|
 | 
						|
static ssize_t
 | 
						|
v9fs_file_read(struct file *filp, char __user *udata, size_t count,
 | 
						|
	       loff_t * offset)
 | 
						|
{
 | 
						|
	int ret;
 | 
						|
	struct p9_fid *fid;
 | 
						|
	size_t size;
 | 
						|
 | 
						|
	p9_debug(P9_DEBUG_VFS, "count %zu offset %lld\n", count, *offset);
 | 
						|
	fid = filp->private_data;
 | 
						|
 | 
						|
	size = fid->iounit ? fid->iounit : fid->clnt->msize - P9_IOHDRSZ;
 | 
						|
	if (count > size)
 | 
						|
		ret = v9fs_file_readn(filp, NULL, udata, count, *offset);
 | 
						|
	else
 | 
						|
		ret = p9_client_read(fid, NULL, udata, *offset, count);
 | 
						|
 | 
						|
	if (ret > 0)
 | 
						|
		*offset += ret;
 | 
						|
 | 
						|
	return ret;
 | 
						|
}
 | 
						|
 | 
						|
ssize_t
 | 
						|
v9fs_file_write_internal(struct inode *inode, struct p9_fid *fid,
 | 
						|
			 const char __user *data, size_t count,
 | 
						|
			 loff_t *offset, int invalidate)
 | 
						|
{
 | 
						|
	int n;
 | 
						|
	loff_t i_size;
 | 
						|
	size_t total = 0;
 | 
						|
	loff_t origin = *offset;
 | 
						|
	unsigned long pg_start, pg_end;
 | 
						|
 | 
						|
	p9_debug(P9_DEBUG_VFS, "data %p count %d offset %x\n",
 | 
						|
		 data, (int)count, (int)*offset);
 | 
						|
 | 
						|
	do {
 | 
						|
		n = p9_client_write(fid, NULL, data+total, origin+total, count);
 | 
						|
		if (n <= 0)
 | 
						|
			break;
 | 
						|
		count -= n;
 | 
						|
		total += n;
 | 
						|
	} while (count > 0);
 | 
						|
 | 
						|
	if (invalidate && (total > 0)) {
 | 
						|
		pg_start = origin >> PAGE_CACHE_SHIFT;
 | 
						|
		pg_end = (origin + total - 1) >> PAGE_CACHE_SHIFT;
 | 
						|
		if (inode->i_mapping && inode->i_mapping->nrpages)
 | 
						|
			invalidate_inode_pages2_range(inode->i_mapping,
 | 
						|
						      pg_start, pg_end);
 | 
						|
		*offset += total;
 | 
						|
		i_size = i_size_read(inode);
 | 
						|
		if (*offset > i_size) {
 | 
						|
			inode_add_bytes(inode, *offset - i_size);
 | 
						|
			i_size_write(inode, *offset);
 | 
						|
		}
 | 
						|
	}
 | 
						|
	if (n < 0)
 | 
						|
		return n;
 | 
						|
 | 
						|
	return total;
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * v9fs_file_write - write to a file
 | 
						|
 * @filp: file pointer to write
 | 
						|
 * @data: data buffer to write data from
 | 
						|
 * @count: size of buffer
 | 
						|
 * @offset: offset at which to write data
 | 
						|
 *
 | 
						|
 */
 | 
						|
static ssize_t
 | 
						|
v9fs_file_write(struct file *filp, const char __user * data,
 | 
						|
		size_t count, loff_t *offset)
 | 
						|
{
 | 
						|
	ssize_t retval = 0;
 | 
						|
	loff_t origin = *offset;
 | 
						|
 | 
						|
 | 
						|
	retval = generic_write_checks(filp, &origin, &count, 0);
 | 
						|
	if (retval)
 | 
						|
		goto out;
 | 
						|
 | 
						|
	retval = -EINVAL;
 | 
						|
	if ((ssize_t) count < 0)
 | 
						|
		goto out;
 | 
						|
	retval = 0;
 | 
						|
	if (!count)
 | 
						|
		goto out;
 | 
						|
 | 
						|
	retval = v9fs_file_write_internal(file_inode(filp),
 | 
						|
					filp->private_data,
 | 
						|
					data, count, &origin, 1);
 | 
						|
	/* update offset on successful write */
 | 
						|
	if (retval > 0)
 | 
						|
		*offset = origin;
 | 
						|
out:
 | 
						|
	return retval;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
static int v9fs_file_fsync(struct file *filp, loff_t start, loff_t end,
 | 
						|
			   int datasync)
 | 
						|
{
 | 
						|
	struct p9_fid *fid;
 | 
						|
	struct inode *inode = filp->f_mapping->host;
 | 
						|
	struct p9_wstat wstat;
 | 
						|
	int retval;
 | 
						|
 | 
						|
	retval = filemap_write_and_wait_range(inode->i_mapping, start, end);
 | 
						|
	if (retval)
 | 
						|
		return retval;
 | 
						|
 | 
						|
	mutex_lock(&inode->i_mutex);
 | 
						|
	p9_debug(P9_DEBUG_VFS, "filp %p datasync %x\n", filp, datasync);
 | 
						|
 | 
						|
	fid = filp->private_data;
 | 
						|
	v9fs_blank_wstat(&wstat);
 | 
						|
 | 
						|
	retval = p9_client_wstat(fid, &wstat);
 | 
						|
	mutex_unlock(&inode->i_mutex);
 | 
						|
 | 
						|
	return retval;
 | 
						|
}
 | 
						|
 | 
						|
int v9fs_file_fsync_dotl(struct file *filp, loff_t start, loff_t end,
 | 
						|
			 int datasync)
 | 
						|
{
 | 
						|
	struct p9_fid *fid;
 | 
						|
	struct inode *inode = filp->f_mapping->host;
 | 
						|
	int retval;
 | 
						|
 | 
						|
	retval = filemap_write_and_wait_range(inode->i_mapping, start, end);
 | 
						|
	if (retval)
 | 
						|
		return retval;
 | 
						|
 | 
						|
	mutex_lock(&inode->i_mutex);
 | 
						|
	p9_debug(P9_DEBUG_VFS, "filp %p datasync %x\n", filp, datasync);
 | 
						|
 | 
						|
	fid = filp->private_data;
 | 
						|
 | 
						|
	retval = p9_client_fsync(fid, datasync);
 | 
						|
	mutex_unlock(&inode->i_mutex);
 | 
						|
 | 
						|
	return retval;
 | 
						|
}
 | 
						|
 | 
						|
static int
 | 
						|
v9fs_file_mmap(struct file *filp, struct vm_area_struct *vma)
 | 
						|
{
 | 
						|
	int retval;
 | 
						|
 | 
						|
 | 
						|
	retval = generic_file_mmap(filp, vma);
 | 
						|
	if (!retval)
 | 
						|
		vma->vm_ops = &v9fs_file_vm_ops;
 | 
						|
 | 
						|
	return retval;
 | 
						|
}
 | 
						|
 | 
						|
static int
 | 
						|
v9fs_mmap_file_mmap(struct file *filp, struct vm_area_struct *vma)
 | 
						|
{
 | 
						|
	int retval;
 | 
						|
	struct inode *inode;
 | 
						|
	struct v9fs_inode *v9inode;
 | 
						|
	struct p9_fid *fid;
 | 
						|
 | 
						|
	inode = file_inode(filp);
 | 
						|
	v9inode = V9FS_I(inode);
 | 
						|
	mutex_lock(&v9inode->v_mutex);
 | 
						|
	if (!v9inode->writeback_fid &&
 | 
						|
	    (vma->vm_flags & VM_WRITE)) {
 | 
						|
		/*
 | 
						|
		 * clone a fid and add it to writeback_fid
 | 
						|
		 * we do it during mmap instead of
 | 
						|
		 * page dirty time via write_begin/page_mkwrite
 | 
						|
		 * because we want write after unlink usecase
 | 
						|
		 * to work.
 | 
						|
		 */
 | 
						|
		fid = v9fs_writeback_fid(filp->f_path.dentry);
 | 
						|
		if (IS_ERR(fid)) {
 | 
						|
			retval = PTR_ERR(fid);
 | 
						|
			mutex_unlock(&v9inode->v_mutex);
 | 
						|
			return retval;
 | 
						|
		}
 | 
						|
		v9inode->writeback_fid = (void *) fid;
 | 
						|
	}
 | 
						|
	mutex_unlock(&v9inode->v_mutex);
 | 
						|
 | 
						|
	retval = generic_file_mmap(filp, vma);
 | 
						|
	if (!retval)
 | 
						|
		vma->vm_ops = &v9fs_mmap_file_vm_ops;
 | 
						|
 | 
						|
	return retval;
 | 
						|
}
 | 
						|
 | 
						|
static int
 | 
						|
v9fs_vm_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
 | 
						|
{
 | 
						|
	struct v9fs_inode *v9inode;
 | 
						|
	struct page *page = vmf->page;
 | 
						|
	struct file *filp = vma->vm_file;
 | 
						|
	struct inode *inode = file_inode(filp);
 | 
						|
 | 
						|
 | 
						|
	p9_debug(P9_DEBUG_VFS, "page %p fid %lx\n",
 | 
						|
		 page, (unsigned long)filp->private_data);
 | 
						|
 | 
						|
	/* Update file times before taking page lock */
 | 
						|
	file_update_time(filp);
 | 
						|
 | 
						|
	v9inode = V9FS_I(inode);
 | 
						|
	/* make sure the cache has finished storing the page */
 | 
						|
	v9fs_fscache_wait_on_page_write(inode, page);
 | 
						|
	BUG_ON(!v9inode->writeback_fid);
 | 
						|
	lock_page(page);
 | 
						|
	if (page->mapping != inode->i_mapping)
 | 
						|
		goto out_unlock;
 | 
						|
	wait_for_stable_page(page);
 | 
						|
 | 
						|
	return VM_FAULT_LOCKED;
 | 
						|
out_unlock:
 | 
						|
	unlock_page(page);
 | 
						|
	return VM_FAULT_NOPAGE;
 | 
						|
}
 | 
						|
 | 
						|
static ssize_t
 | 
						|
v9fs_direct_read(struct file *filp, char __user *udata, size_t count,
 | 
						|
		 loff_t *offsetp)
 | 
						|
{
 | 
						|
	loff_t size, offset;
 | 
						|
	struct inode *inode;
 | 
						|
	struct address_space *mapping;
 | 
						|
 | 
						|
	offset = *offsetp;
 | 
						|
	mapping = filp->f_mapping;
 | 
						|
	inode = mapping->host;
 | 
						|
	if (!count)
 | 
						|
		return 0;
 | 
						|
	size = i_size_read(inode);
 | 
						|
	if (offset < size)
 | 
						|
		filemap_write_and_wait_range(mapping, offset,
 | 
						|
					     offset + count - 1);
 | 
						|
 | 
						|
	return v9fs_file_read(filp, udata, count, offsetp);
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * v9fs_cached_file_read - read from a file
 | 
						|
 * @filp: file pointer to read
 | 
						|
 * @data: user data buffer to read data into
 | 
						|
 * @count: size of buffer
 | 
						|
 * @offset: offset at which to read data
 | 
						|
 *
 | 
						|
 */
 | 
						|
static ssize_t
 | 
						|
v9fs_cached_file_read(struct file *filp, char __user *data, size_t count,
 | 
						|
		      loff_t *offset)
 | 
						|
{
 | 
						|
	if (filp->f_flags & O_DIRECT)
 | 
						|
		return v9fs_direct_read(filp, data, count, offset);
 | 
						|
	return new_sync_read(filp, data, count, offset);
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * v9fs_mmap_file_read - read from a file
 | 
						|
 * @filp: file pointer to read
 | 
						|
 * @data: user data buffer to read data into
 | 
						|
 * @count: size of buffer
 | 
						|
 * @offset: offset at which to read data
 | 
						|
 *
 | 
						|
 */
 | 
						|
static ssize_t
 | 
						|
v9fs_mmap_file_read(struct file *filp, char __user *data, size_t count,
 | 
						|
		      loff_t *offset)
 | 
						|
{
 | 
						|
	/* TODO: Check if there are dirty pages */
 | 
						|
	return v9fs_file_read(filp, data, count, offset);
 | 
						|
}
 | 
						|
 | 
						|
static ssize_t
 | 
						|
v9fs_direct_write(struct file *filp, const char __user * data,
 | 
						|
		  size_t count, loff_t *offsetp)
 | 
						|
{
 | 
						|
	loff_t offset;
 | 
						|
	ssize_t retval;
 | 
						|
	struct inode *inode;
 | 
						|
	struct address_space *mapping;
 | 
						|
 | 
						|
	offset = *offsetp;
 | 
						|
	mapping = filp->f_mapping;
 | 
						|
	inode = mapping->host;
 | 
						|
	if (!count)
 | 
						|
		return 0;
 | 
						|
 | 
						|
	mutex_lock(&inode->i_mutex);
 | 
						|
	retval = filemap_write_and_wait_range(mapping, offset,
 | 
						|
					      offset + count - 1);
 | 
						|
	if (retval)
 | 
						|
		goto err_out;
 | 
						|
	/*
 | 
						|
	 * After a write we want buffered reads to be sure to go to disk to get
 | 
						|
	 * the new data.  We invalidate clean cached page from the region we're
 | 
						|
	 * about to write.  We do this *before* the write so that if we fail
 | 
						|
	 * here we fall back to buffered write
 | 
						|
	 */
 | 
						|
	if (mapping->nrpages) {
 | 
						|
		pgoff_t pg_start = offset >> PAGE_CACHE_SHIFT;
 | 
						|
		pgoff_t pg_end   = (offset + count - 1) >> PAGE_CACHE_SHIFT;
 | 
						|
 | 
						|
		retval = invalidate_inode_pages2_range(mapping,
 | 
						|
							pg_start, pg_end);
 | 
						|
		/*
 | 
						|
		 * If a page can not be invalidated, fall back
 | 
						|
		 * to buffered write.
 | 
						|
		 */
 | 
						|
		if (retval) {
 | 
						|
			if (retval == -EBUSY)
 | 
						|
				goto buff_write;
 | 
						|
			goto err_out;
 | 
						|
		}
 | 
						|
	}
 | 
						|
	retval = v9fs_file_write(filp, data, count, offsetp);
 | 
						|
err_out:
 | 
						|
	mutex_unlock(&inode->i_mutex);
 | 
						|
	return retval;
 | 
						|
 | 
						|
buff_write:
 | 
						|
	mutex_unlock(&inode->i_mutex);
 | 
						|
	return new_sync_write(filp, data, count, offsetp);
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * v9fs_cached_file_write - write to a file
 | 
						|
 * @filp: file pointer to write
 | 
						|
 * @data: data buffer to write data from
 | 
						|
 * @count: size of buffer
 | 
						|
 * @offset: offset at which to write data
 | 
						|
 *
 | 
						|
 */
 | 
						|
static ssize_t
 | 
						|
v9fs_cached_file_write(struct file *filp, const char __user * data,
 | 
						|
		       size_t count, loff_t *offset)
 | 
						|
{
 | 
						|
 | 
						|
	if (filp->f_flags & O_DIRECT)
 | 
						|
		return v9fs_direct_write(filp, data, count, offset);
 | 
						|
	return new_sync_write(filp, data, count, offset);
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/**
 | 
						|
 * v9fs_mmap_file_write - write to a file
 | 
						|
 * @filp: file pointer to write
 | 
						|
 * @data: data buffer to write data from
 | 
						|
 * @count: size of buffer
 | 
						|
 * @offset: offset at which to write data
 | 
						|
 *
 | 
						|
 */
 | 
						|
static ssize_t
 | 
						|
v9fs_mmap_file_write(struct file *filp, const char __user *data,
 | 
						|
		       size_t count, loff_t *offset)
 | 
						|
{
 | 
						|
	/*
 | 
						|
	 * TODO: invalidate mmaps on filp's inode between
 | 
						|
	 * offset and offset+count
 | 
						|
	 */
 | 
						|
	return v9fs_file_write(filp, data, count, offset);
 | 
						|
}
 | 
						|
 | 
						|
static void v9fs_mmap_vm_close(struct vm_area_struct *vma)
 | 
						|
{
 | 
						|
	struct inode *inode;
 | 
						|
 | 
						|
	struct writeback_control wbc = {
 | 
						|
		.nr_to_write = LONG_MAX,
 | 
						|
		.sync_mode = WB_SYNC_ALL,
 | 
						|
		.range_start = vma->vm_pgoff * PAGE_SIZE,
 | 
						|
		 /* absolute end, byte at end included */
 | 
						|
		.range_end = vma->vm_pgoff * PAGE_SIZE +
 | 
						|
			(vma->vm_end - vma->vm_start - 1),
 | 
						|
	};
 | 
						|
 | 
						|
 | 
						|
	p9_debug(P9_DEBUG_VFS, "9p VMA close, %p, flushing", vma);
 | 
						|
 | 
						|
	inode = file_inode(vma->vm_file);
 | 
						|
 | 
						|
	if (!mapping_cap_writeback_dirty(inode->i_mapping))
 | 
						|
		wbc.nr_to_write = 0;
 | 
						|
 | 
						|
	might_sleep();
 | 
						|
	sync_inode(inode, &wbc);
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
static const struct vm_operations_struct v9fs_file_vm_ops = {
 | 
						|
	.fault = filemap_fault,
 | 
						|
	.map_pages = filemap_map_pages,
 | 
						|
	.page_mkwrite = v9fs_vm_page_mkwrite,
 | 
						|
	.remap_pages = generic_file_remap_pages,
 | 
						|
};
 | 
						|
 | 
						|
static const struct vm_operations_struct v9fs_mmap_file_vm_ops = {
 | 
						|
	.close = v9fs_mmap_vm_close,
 | 
						|
	.fault = filemap_fault,
 | 
						|
	.map_pages = filemap_map_pages,
 | 
						|
	.page_mkwrite = v9fs_vm_page_mkwrite,
 | 
						|
	.remap_pages = generic_file_remap_pages,
 | 
						|
};
 | 
						|
 | 
						|
 | 
						|
const struct file_operations v9fs_cached_file_operations = {
 | 
						|
	.llseek = generic_file_llseek,
 | 
						|
	.read = v9fs_cached_file_read,
 | 
						|
	.write = v9fs_cached_file_write,
 | 
						|
	.read_iter = generic_file_read_iter,
 | 
						|
	.write_iter = generic_file_write_iter,
 | 
						|
	.open = v9fs_file_open,
 | 
						|
	.release = v9fs_dir_release,
 | 
						|
	.lock = v9fs_file_lock,
 | 
						|
	.mmap = v9fs_file_mmap,
 | 
						|
	.fsync = v9fs_file_fsync,
 | 
						|
};
 | 
						|
 | 
						|
const struct file_operations v9fs_cached_file_operations_dotl = {
 | 
						|
	.llseek = generic_file_llseek,
 | 
						|
	.read = v9fs_cached_file_read,
 | 
						|
	.write = v9fs_cached_file_write,
 | 
						|
	.read_iter = generic_file_read_iter,
 | 
						|
	.write_iter = generic_file_write_iter,
 | 
						|
	.open = v9fs_file_open,
 | 
						|
	.release = v9fs_dir_release,
 | 
						|
	.lock = v9fs_file_lock_dotl,
 | 
						|
	.flock = v9fs_file_flock_dotl,
 | 
						|
	.mmap = v9fs_file_mmap,
 | 
						|
	.fsync = v9fs_file_fsync_dotl,
 | 
						|
};
 | 
						|
 | 
						|
const struct file_operations v9fs_file_operations = {
 | 
						|
	.llseek = generic_file_llseek,
 | 
						|
	.read = v9fs_file_read,
 | 
						|
	.write = v9fs_file_write,
 | 
						|
	.open = v9fs_file_open,
 | 
						|
	.release = v9fs_dir_release,
 | 
						|
	.lock = v9fs_file_lock,
 | 
						|
	.mmap = generic_file_readonly_mmap,
 | 
						|
	.fsync = v9fs_file_fsync,
 | 
						|
};
 | 
						|
 | 
						|
const struct file_operations v9fs_file_operations_dotl = {
 | 
						|
	.llseek = generic_file_llseek,
 | 
						|
	.read = v9fs_file_read,
 | 
						|
	.write = v9fs_file_write,
 | 
						|
	.open = v9fs_file_open,
 | 
						|
	.release = v9fs_dir_release,
 | 
						|
	.lock = v9fs_file_lock_dotl,
 | 
						|
	.flock = v9fs_file_flock_dotl,
 | 
						|
	.mmap = generic_file_readonly_mmap,
 | 
						|
	.fsync = v9fs_file_fsync_dotl,
 | 
						|
};
 | 
						|
 | 
						|
const struct file_operations v9fs_mmap_file_operations = {
 | 
						|
	.llseek = generic_file_llseek,
 | 
						|
	.read = v9fs_mmap_file_read,
 | 
						|
	.write = v9fs_mmap_file_write,
 | 
						|
	.open = v9fs_file_open,
 | 
						|
	.release = v9fs_dir_release,
 | 
						|
	.lock = v9fs_file_lock,
 | 
						|
	.mmap = v9fs_mmap_file_mmap,
 | 
						|
	.fsync = v9fs_file_fsync,
 | 
						|
};
 | 
						|
 | 
						|
const struct file_operations v9fs_mmap_file_operations_dotl = {
 | 
						|
	.llseek = generic_file_llseek,
 | 
						|
	.read = v9fs_mmap_file_read,
 | 
						|
	.write = v9fs_mmap_file_write,
 | 
						|
	.open = v9fs_file_open,
 | 
						|
	.release = v9fs_dir_release,
 | 
						|
	.lock = v9fs_file_lock_dotl,
 | 
						|
	.flock = v9fs_file_flock_dotl,
 | 
						|
	.mmap = v9fs_mmap_file_mmap,
 | 
						|
	.fsync = v9fs_file_fsync_dotl,
 | 
						|
};
 |