[mirror_ubuntu-hirsute-kernel.git] / fs / sync.c

/*
 * High-level sync()-related operations
 */

#include <linux/kernel.h>
#include <linux/file.h>
#include <linux/fs.h>
#include <linux/slab.h>
#include <linux/export.h>
#include <linux/namei.h>
#include <linux/sched.h>
#include <linux/writeback.h>
#include <linux/syscalls.h>
#include <linux/linkage.h>
#include <linux/pagemap.h>
#include <linux/quotaops.h>
#include <linux/backing-dev.h>
#include "internal.h"

#define VALID_FLAGS (SYNC_FILE_RANGE_WAIT_BEFORE|SYNC_FILE_RANGE_WRITE| \
			SYNC_FILE_RANGE_WAIT_AFTER)

/*
 * Do the filesystem syncing work. For simple filesystems
 * writeback_inodes_sb(sb) just dirties buffers with inodes so we have to
 * submit IO for these buffers via __sync_blockdev(). This also speeds up the
 * wait == 1 case since in that case write_inode() functions do
 * sync_dirty_buffer() and thus effectively write one block at a time.
 */
static int __sync_filesystem(struct super_block *sb, int wait)
{
	if (sb->s_qcop && sb->s_qcop->quota_sync)
		sb->s_qcop->quota_sync(sb, -1, wait);

	if (wait)
		sync_inodes_sb(sb);
	else
		writeback_inodes_sb(sb, WB_REASON_SYNC);

	if (sb->s_op->sync_fs)
		sb->s_op->sync_fs(sb, wait);
	return __sync_blockdev(sb->s_bdev, wait);
}

/*
 * Write out and wait upon all dirty data associated with this
 * superblock.  Filesystem data as well as the underlying block
 * device.  Takes the superblock lock.
 */
int sync_filesystem(struct super_block *sb)
{
	int ret;

	/*
	 * We need to be protected against the filesystem going from
	 * r/o to r/w or vice versa.
	 */
	WARN_ON(!rwsem_is_locked(&sb->s_umount));

	/*
	 * No point in syncing out anything if the filesystem is read-only.
	 */
	if (sb->s_flags & MS_RDONLY)
		return 0;

	ret = __sync_filesystem(sb, 0);
	if (ret < 0)
		return ret;
	return __sync_filesystem(sb, 1);
}
EXPORT_SYMBOL_GPL(sync_filesystem);

static void sync_one_sb(struct super_block *sb, void *arg)
{
	if (!(sb->s_flags & MS_RDONLY))
		__sync_filesystem(sb, *(int *)arg);
}
/*
 * Sync all the data for all the filesystems (called by sys_sync() and
 * emergency sync)
 */
static void sync_filesystems(int wait)
{
	iterate_supers(sync_one_sb, &wait);
}

/*
 * sync everything.  Start out by waking pdflush, because that writes back
 * all queues in parallel.
 */
SYSCALL_DEFINE0(sync)
{
	wakeup_flusher_threads(0, WB_REASON_SYNC);
	sync_filesystems(0);
	sync_filesystems(1);
	if (unlikely(laptop_mode))
		laptop_sync_completion();
	return 0;
}

static void do_sync_work(struct work_struct *work)
{
	/*
	 * Sync twice to reduce the possibility we skipped some inodes / pages
	 * because they were temporarily locked
	 */
	sync_filesystems(0);
	sync_filesystems(0);
	printk("Emergency Sync complete\n");
	kfree(work);
}

void emergency_sync(void)
{
	struct work_struct *work;

	work = kmalloc(sizeof(*work), GFP_ATOMIC);
	if (work) {
		INIT_WORK(work, do_sync_work);
		schedule_work(work);
	}
}

/*
 * sync a single super
 */
SYSCALL_DEFINE1(syncfs, int, fd)
{
	struct file *file;
	struct super_block *sb;
	int ret;
	int fput_needed;

	file = fget_light(fd, &fput_needed);
	if (!file)
		return -EBADF;
	sb = file->f_dentry->d_sb;

	down_read(&sb->s_umount);
	ret = sync_filesystem(sb);
	up_read(&sb->s_umount);

	fput_light(file, fput_needed);
	return ret;
}

/**
 * vfs_fsync_range - helper to sync a range of data & metadata to disk
 * @file:		file to sync
 * @start:		offset in bytes of the beginning of data range to sync
 * @end:		offset in bytes of the end of data range (inclusive)
 * @datasync:		perform only datasync
 *
 * Write back data in range @start..@end and metadata for @file to disk.  If
 * @datasync is set only metadata needed to access modified file data is
 * written.
 */
int vfs_fsync_range(struct file *file, loff_t start, loff_t end, int datasync)
{
	if (!file->f_op || !file->f_op->fsync)
		return -EINVAL;
	return file->f_op->fsync(file, start, end, datasync);
}
EXPORT_SYMBOL(vfs_fsync_range);

/**
 * vfs_fsync - perform a fsync or fdatasync on a file
 * @file:		file to sync
 * @datasync:		only perform a fdatasync operation
 *
 * Write back data and metadata for @file to disk.  If @datasync is
 * set only metadata needed to access modified file data is written.
 */
int vfs_fsync(struct file *file, int datasync)
{
	return vfs_fsync_range(file, 0, LLONG_MAX, datasync);
}
EXPORT_SYMBOL(vfs_fsync);

static int do_fsync(unsigned int fd, int datasync)
{
	struct file *file;
	int ret = -EBADF;
	int fput_needed;

	file = fget_light(fd, &fput_needed);
	if (file) {
		ret = vfs_fsync(file, datasync);
		fput_light(file, fput_needed);
	}
	return ret;
}

SYSCALL_DEFINE1(fsync, unsigned int, fd)
{
	return do_fsync(fd, 0);
}

SYSCALL_DEFINE1(fdatasync, unsigned int, fd)
{
	return do_fsync(fd, 1);
}

/**
 * generic_write_sync - perform syncing after a write if file / inode is sync
 * @file:	file to which the write happened
 * @pos:	offset where the write started
 * @count:	length of the write
 *
 * This is just a simple wrapper about our general syncing function.
 */
int generic_write_sync(struct file *file, loff_t pos, loff_t count)
{
	if (!(file->f_flags & O_DSYNC) && !IS_SYNC(file->f_mapping->host))
		return 0;
	return vfs_fsync_range(file, pos, pos + count - 1,
			       (file->f_flags & __O_SYNC) ? 0 : 1);
}
EXPORT_SYMBOL(generic_write_sync);

/*
 * sys_sync_file_range() permits finely controlled syncing over a segment of
 * a file in the range offset .. (offset+nbytes-1) inclusive.  If nbytes is
 * zero then sys_sync_file_range() will operate from offset out to EOF.
 *
 * The flag bits are:
 *
 * SYNC_FILE_RANGE_WAIT_BEFORE: wait upon writeout of all pages in the range
 * before performing the write.
 *
 * SYNC_FILE_RANGE_WRITE: initiate writeout of all those dirty pages in the
 * range which are not presently under writeback. Note that this may block for
 * significant periods due to exhaustion of disk request structures.
 *
 * SYNC_FILE_RANGE_WAIT_AFTER: wait upon writeout of all pages in the range
 * after performing the write.
 *
 * Useful combinations of the flag bits are:
 *
 * SYNC_FILE_RANGE_WAIT_BEFORE|SYNC_FILE_RANGE_WRITE: ensures that all pages
 * in the range which were dirty on entry to sys_sync_file_range() are placed
 * under writeout.  This is a start-write-for-data-integrity operation.
 *
 * SYNC_FILE_RANGE_WRITE: start writeout of all dirty pages in the range which
 * are not presently under writeout.  This is an asynchronous flush-to-disk
 * operation.  Not suitable for data integrity operations.
 *
 * SYNC_FILE_RANGE_WAIT_BEFORE (or SYNC_FILE_RANGE_WAIT_AFTER): wait for
 * completion of writeout of all pages in the range.  This will be used after an
 * earlier SYNC_FILE_RANGE_WAIT_BEFORE|SYNC_FILE_RANGE_WRITE operation to wait
 * for that operation to complete and to return the result.
 *
 * SYNC_FILE_RANGE_WAIT_BEFORE|SYNC_FILE_RANGE_WRITE|SYNC_FILE_RANGE_WAIT_AFTER:
 * a traditional sync() operation.  This is a write-for-data-integrity operation
 * which will ensure that all pages in the range which were dirty on entry to
 * sys_sync_file_range() are committed to disk.
 *
 *
 * SYNC_FILE_RANGE_WAIT_BEFORE and SYNC_FILE_RANGE_WAIT_AFTER will detect any
 * I/O errors or ENOSPC conditions and will return those to the caller, after
 * clearing the EIO and ENOSPC flags in the address_space.
 *
 * It should be noted that none of these operations write out the file's
 * metadata.  So unless the application is strictly performing overwrites of
 * already-instantiated disk blocks, there are no guarantees here that the data
 * will be available after a crash.
 */
SYSCALL_DEFINE(sync_file_range)(int fd, loff_t offset, loff_t nbytes,
				unsigned int flags)
{
	int ret;
	struct file *file;
	struct address_space *mapping;
	loff_t endbyte;			/* inclusive */
	int fput_needed;
	umode_t i_mode;

	ret = -EINVAL;
	if (flags & ~VALID_FLAGS)
		goto out;

	endbyte = offset + nbytes;

	if ((s64)offset < 0)
		goto out;
	if ((s64)endbyte < 0)
		goto out;
	if (endbyte < offset)
		goto out;

	if (sizeof(pgoff_t) == 4) {
		if (offset >= (0x100000000ULL << PAGE_CACHE_SHIFT)) {
			/*
			 * The range starts outside a 32 bit machine's
			 * pagecache addressing capabilities.  Let it "succeed"
			 */
			ret = 0;
			goto out;
		}
		if (endbyte >= (0x100000000ULL << PAGE_CACHE_SHIFT)) {
			/*
			 * Out to EOF
			 */
			nbytes = 0;
		}
	}

	if (nbytes == 0)
		endbyte = LLONG_MAX;
	else
		endbyte--;		/* inclusive */

	ret = -EBADF;
	file = fget_light(fd, &fput_needed);
	if (!file)
		goto out;

	i_mode = file->f_path.dentry->d_inode->i_mode;
	ret = -ESPIPE;
	if (!S_ISREG(i_mode) && !S_ISBLK(i_mode) && !S_ISDIR(i_mode) &&
			!S_ISLNK(i_mode))
		goto out_put;

	mapping = file->f_mapping;
	if (!mapping) {
		ret = -EINVAL;
		goto out_put;
	}

	ret = 0;
	if (flags & SYNC_FILE_RANGE_WAIT_BEFORE) {
		ret = filemap_fdatawait_range(mapping, offset, endbyte);
		if (ret < 0)
			goto out_put;
	}

	if (flags & SYNC_FILE_RANGE_WRITE) {
		ret = filemap_fdatawrite_range(mapping, offset, endbyte);
		if (ret < 0)
			goto out_put;
	}

	if (flags & SYNC_FILE_RANGE_WAIT_AFTER)
		ret = filemap_fdatawait_range(mapping, offset, endbyte);

out_put:
	fput_light(file, fput_needed);
out:
	return ret;
}
#ifdef CONFIG_HAVE_SYSCALL_WRAPPERS
asmlinkage long SyS_sync_file_range(long fd, loff_t offset, loff_t nbytes,
				    long flags)
{
	return SYSC_sync_file_range((int) fd, offset, nbytes,
				    (unsigned int) flags);
}
SYSCALL_ALIAS(sys_sync_file_range, SyS_sync_file_range);
#endif

/* It would be nice if people remember that not all the world's an i386
   when they introduce new system calls */
SYSCALL_DEFINE(sync_file_range2)(int fd, unsigned int flags,
				 loff_t offset, loff_t nbytes)
{
	return sys_sync_file_range(fd, offset, nbytes, flags);
}
#ifdef CONFIG_HAVE_SYSCALL_WRAPPERS
asmlinkage long SyS_sync_file_range2(long fd, long flags,
				     loff_t offset, loff_t nbytes)
{
	return SYSC_sync_file_range2((int) fd, (unsigned int) flags,
				     offset, nbytes);
}
SYSCALL_ALIAS(sys_sync_file_range2, SyS_sync_file_range2);
#endif
Commit	Line	Data
f79e2abb AM	1	/*
	2	* High-level sync()-related operations
	3	*/
	4
	5	#include <linux/kernel.h>
	6	#include <linux/file.h>
	7	#include <linux/fs.h>
5a0e3ad6	8	#include <linux/slab.h>
630d9c47	9	#include <linux/export.h>
b7ed78f5	10	#include <linux/namei.h>
914e2637	11	#include <linux/sched.h>
f79e2abb AM	12	#include <linux/writeback.h>
	13	#include <linux/syscalls.h>
	14	#include <linux/linkage.h>
	15	#include <linux/pagemap.h>
cf9a2ae8	16	#include <linux/quotaops.h>
5129a469	17	#include <linux/backing-dev.h>
5a3e5cb8	18	#include "internal.h"
f79e2abb AM	19
	20	#define VALID_FLAGS (SYNC_FILE_RANGE_WAIT_BEFORE\|SYNC_FILE_RANGE_WRITE\| \
	21	SYNC_FILE_RANGE_WAIT_AFTER)
	22
c15c54f5	23	/*
d8a8559c JA	24	* Do the filesystem syncing work. For simple filesystems
	25	* writeback_inodes_sb(sb) just dirties buffers with inodes so we have to
	26	* submit IO for these buffers via __sync_blockdev(). This also speeds up the
	27	* wait == 1 case since in that case write_inode() functions do
	28	* sync_dirty_buffer() and thus effectively write one block at a time.
c15c54f5	29	*/
60b0680f	30	static int __sync_filesystem(struct super_block *sb, int wait)
c15c54f5	31	{
5fb324ad CH	32	if (sb->s_qcop && sb->s_qcop->quota_sync)
	33	sb->s_qcop->quota_sync(sb, -1, wait);
	34
	35	if (wait)
d8a8559c	36	sync_inodes_sb(sb);
5fb324ad	37	else
0e175a18	38	writeback_inodes_sb(sb, WB_REASON_SYNC);
5fb324ad	39
c15c54f5 JK	40	if (sb->s_op->sync_fs)
	41	sb->s_op->sync_fs(sb, wait);
	42	return __sync_blockdev(sb->s_bdev, wait);
	43	}
	44
	45	/*
	46	* Write out and wait upon all dirty data associated with this
	47	* superblock. Filesystem data as well as the underlying block
	48	* device. Takes the superblock lock.
	49	*/
60b0680f	50	int sync_filesystem(struct super_block *sb)
c15c54f5 JK	51	{
	52	int ret;
	53
5af7926f CH	54	/*
	55	* We need to be protected against the filesystem going from
	56	* r/o to r/w or vice versa.
	57	*/
	58	WARN_ON(!rwsem_is_locked(&sb->s_umount));
	59
	60	/*
	61	* No point in syncing out anything if the filesystem is read-only.
	62	*/
	63	if (sb->s_flags & MS_RDONLY)
	64	return 0;
	65
60b0680f	66	ret = __sync_filesystem(sb, 0);
c15c54f5 JK	67	if (ret < 0)
c15c54f5 JK	68	return ret;
60b0680f	69	return __sync_filesystem(sb, 1);
c15c54f5	70	}
60b0680f	71	EXPORT_SYMBOL_GPL(sync_filesystem);
c15c54f5	72
01a05b33 AV	73	static void sync_one_sb(struct super_block sb, void arg)
01a05b33 AV	74	{
95f28604	75	if (!(sb->s_flags & MS_RDONLY))
01a05b33 AV	76	__sync_filesystem(sb, (int )arg);
01a05b33 AV	77	}
c15c54f5 JK	78	/*
	79	* Sync all the data for all the filesystems (called by sys_sync() and
	80	* emergency sync)
c15c54f5 JK	81	*/
	82	static void sync_filesystems(int wait)
	83	{
01a05b33	84	iterate_supers(sync_one_sb, &wait);
c15c54f5 JK	85	}
c15c54f5 JK	86
3beab0b4 ZY	87	/*
	88	* sync everything. Start out by waking pdflush, because that writes back
	89	* all queues in parallel.
	90	*/
5cee5815	91	SYSCALL_DEFINE0(sync)
cf9a2ae8	92	{
0e175a18	93	wakeup_flusher_threads(0, WB_REASON_SYNC);
5cee5815 JK	94	sync_filesystems(0);
5cee5815 JK	95	sync_filesystems(1);
cf9a2ae8 DH	96	if (unlikely(laptop_mode))
cf9a2ae8 DH	97	laptop_sync_completion();
cf9a2ae8 DH	98	return 0;
	99	}
	100
a2a9537a JA	101	static void do_sync_work(struct work_struct *work)
a2a9537a JA	102	{
5cee5815 JK	103	/*
	104	* Sync twice to reduce the possibility we skipped some inodes / pages
	105	* because they were temporarily locked
	106	*/
	107	sync_filesystems(0);
	108	sync_filesystems(0);
	109	printk("Emergency Sync complete\n");
a2a9537a JA	110	kfree(work);
	111	}
	112
cf9a2ae8 DH	113	void emergency_sync(void)
cf9a2ae8 DH	114	{
a2a9537a JA	115	struct work_struct *work;
	116
	117	work = kmalloc(sizeof(*work), GFP_ATOMIC);
	118	if (work) {
	119	INIT_WORK(work, do_sync_work);
	120	schedule_work(work);
	121	}
cf9a2ae8 DH	122	}
cf9a2ae8 DH	123
b7ed78f5 SW	124	/*
	125	* sync a single super
	126	*/
	127	SYSCALL_DEFINE1(syncfs, int, fd)
	128	{
	129	struct file *file;
	130	struct super_block *sb;
	131	int ret;
	132	int fput_needed;
	133
	134	file = fget_light(fd, &fput_needed);
	135	if (!file)
	136	return -EBADF;
	137	sb = file->f_dentry->d_sb;
	138
	139	down_read(&sb->s_umount);
	140	ret = sync_filesystem(sb);
	141	up_read(&sb->s_umount);
	142
	143	fput_light(file, fput_needed);
	144	return ret;
	145	}
	146
4c728ef5	147	/**
148f948b	148	* vfs_fsync_range - helper to sync a range of data & metadata to disk
4c728ef5	149	* @file: file to sync
148f948b JK	150	* @start: offset in bytes of the beginning of data range to sync
	151	* @end: offset in bytes of the end of data range (inclusive)
	152	* @datasync: perform only datasync
4c728ef5	153	*
148f948b JK	154	* Write back data in range @start..@end and metadata for @file to disk. If
	155	* @datasync is set only metadata needed to access modified file data is
	156	* written.
4c728ef5	157	*/
8018ab05	158	int vfs_fsync_range(struct file *file, loff_t start, loff_t end, int datasync)
cf9a2ae8	159	{
02c24a82 JB	160	if (!file->f_op \|\| !file->f_op->fsync)
	161	return -EINVAL;
	162	return file->f_op->fsync(file, start, end, datasync);
cf9a2ae8	163	}
148f948b JK	164	EXPORT_SYMBOL(vfs_fsync_range);
	165
	166	/**
	167	* vfs_fsync - perform a fsync or fdatasync on a file
	168	* @file: file to sync
148f948b JK	169	* @datasync: only perform a fdatasync operation
	170	*
	171	* Write back data and metadata for @file to disk. If @datasync is
	172	* set only metadata needed to access modified file data is written.
148f948b	173	*/
8018ab05	174	int vfs_fsync(struct file *file, int datasync)
148f948b	175	{
8018ab05	176	return vfs_fsync_range(file, 0, LLONG_MAX, datasync);
148f948b	177	}
4c728ef5	178	EXPORT_SYMBOL(vfs_fsync);
cf9a2ae8	179
4c728ef5	180	static int do_fsync(unsigned int fd, int datasync)
cf9a2ae8 DH	181	{
	182	struct file *file;
	183	int ret = -EBADF;
c2bd6c11	184	int fput_needed;
cf9a2ae8	185
c2bd6c11	186	file = fget_light(fd, &fput_needed);
cf9a2ae8	187	if (file) {
8018ab05	188	ret = vfs_fsync(file, datasync);
c2bd6c11	189	fput_light(file, fput_needed);
cf9a2ae8 DH	190	}
	191	return ret;
	192	}
	193
a5f8fa9e	194	SYSCALL_DEFINE1(fsync, unsigned int, fd)
cf9a2ae8	195	{
4c728ef5	196	return do_fsync(fd, 0);
cf9a2ae8 DH	197	}
cf9a2ae8 DH	198
a5f8fa9e	199	SYSCALL_DEFINE1(fdatasync, unsigned int, fd)
cf9a2ae8	200	{
4c728ef5	201	return do_fsync(fd, 1);
cf9a2ae8 DH	202	}
cf9a2ae8 DH	203
148f948b JK	204	/**
	205	* generic_write_sync - perform syncing after a write if file / inode is sync
	206	* @file: file to which the write happened
	207	* @pos: offset where the write started
	208	* @count: length of the write
	209	*
	210	* This is just a simple wrapper about our general syncing function.
	211	*/
	212	int generic_write_sync(struct file *file, loff_t pos, loff_t count)
	213	{
6b2f3d1f	214	if (!(file->f_flags & O_DSYNC) && !IS_SYNC(file->f_mapping->host))
148f948b	215	return 0;
8018ab05	216	return vfs_fsync_range(file, pos, pos + count - 1,
6b2f3d1f	217	(file->f_flags & __O_SYNC) ? 0 : 1);
148f948b JK	218	}
	219	EXPORT_SYMBOL(generic_write_sync);
	220
f79e2abb AM	221	/*
	222	* sys_sync_file_range() permits finely controlled syncing over a segment of
	223	* a file in the range offset .. (offset+nbytes-1) inclusive. If nbytes is
	224	* zero then sys_sync_file_range() will operate from offset out to EOF.
	225	*
	226	* The flag bits are:
	227	*
	228	* SYNC_FILE_RANGE_WAIT_BEFORE: wait upon writeout of all pages in the range
	229	* before performing the write.
	230	*
	231	* SYNC_FILE_RANGE_WRITE: initiate writeout of all those dirty pages in the
cce77081 PM	232	* range which are not presently under writeback. Note that this may block for
cce77081 PM	233	* significant periods due to exhaustion of disk request structures.
f79e2abb AM	234	*
	235	* SYNC_FILE_RANGE_WAIT_AFTER: wait upon writeout of all pages in the range
	236	* after performing the write.
	237	*
	238	* Useful combinations of the flag bits are:
	239	*
	240	* SYNC_FILE_RANGE_WAIT_BEFORE\|SYNC_FILE_RANGE_WRITE: ensures that all pages
	241	* in the range which were dirty on entry to sys_sync_file_range() are placed
	242	* under writeout. This is a start-write-for-data-integrity operation.
	243	*
	244	* SYNC_FILE_RANGE_WRITE: start writeout of all dirty pages in the range which
	245	* are not presently under writeout. This is an asynchronous flush-to-disk
	246	* operation. Not suitable for data integrity operations.
	247	*
	248	* SYNC_FILE_RANGE_WAIT_BEFORE (or SYNC_FILE_RANGE_WAIT_AFTER): wait for
	249	* completion of writeout of all pages in the range. This will be used after an
	250	* earlier SYNC_FILE_RANGE_WAIT_BEFORE\|SYNC_FILE_RANGE_WRITE operation to wait
	251	* for that operation to complete and to return the result.
	252	*
	253	* SYNC_FILE_RANGE_WAIT_BEFORE\|SYNC_FILE_RANGE_WRITE\|SYNC_FILE_RANGE_WAIT_AFTER:
	254	* a traditional sync() operation. This is a write-for-data-integrity operation
	255	* which will ensure that all pages in the range which were dirty on entry to
	256	* sys_sync_file_range() are committed to disk.
	257	*
	258	*
	259	* SYNC_FILE_RANGE_WAIT_BEFORE and SYNC_FILE_RANGE_WAIT_AFTER will detect any
	260	* I/O errors or ENOSPC conditions and will return those to the caller, after
	261	* clearing the EIO and ENOSPC flags in the address_space.
	262	*
	263	* It should be noted that none of these operations write out the file's
	264	* metadata. So unless the application is strictly performing overwrites of
	265	* already-instantiated disk blocks, there are no guarantees here that the data
	266	* will be available after a crash.
	267	*/
6673e0c3 HC	268	SYSCALL_DEFINE(sync_file_range)(int fd, loff_t offset, loff_t nbytes,
6673e0c3 HC	269	unsigned int flags)
f79e2abb AM	270	{
	271	int ret;
	272	struct file *file;
7a0ad10c	273	struct address_space *mapping;
f79e2abb AM	274	loff_t endbyte; /* inclusive */
	275	int fput_needed;
	276	umode_t i_mode;
	277
	278	ret = -EINVAL;
	279	if (flags & ~VALID_FLAGS)
	280	goto out;
	281
	282	endbyte = offset + nbytes;
	283
	284	if ((s64)offset < 0)
	285	goto out;
	286	if ((s64)endbyte < 0)
	287	goto out;
	288	if (endbyte < offset)
	289	goto out;
	290
	291	if (sizeof(pgoff_t) == 4) {
	292	if (offset >= (0x100000000ULL << PAGE_CACHE_SHIFT)) {
	293	/*
	294	* The range starts outside a 32 bit machine's
	295	* pagecache addressing capabilities. Let it "succeed"
	296	*/
	297	ret = 0;
	298	goto out;
	299	}
	300	if (endbyte >= (0x100000000ULL << PAGE_CACHE_SHIFT)) {
	301	/*
	302	* Out to EOF
	303	*/
	304	nbytes = 0;
	305	}
	306	}
	307
	308	if (nbytes == 0)
111ebb6e	309	endbyte = LLONG_MAX;
f79e2abb AM	310	else
	311	endbyte--; /* inclusive */
	312
	313	ret = -EBADF;
	314	file = fget_light(fd, &fput_needed);
	315	if (!file)
	316	goto out;
	317
0f7fc9e4	318	i_mode = file->f_path.dentry->d_inode->i_mode;
f79e2abb AM	319	ret = -ESPIPE;
	320	if (!S_ISREG(i_mode) && !S_ISBLK(i_mode) && !S_ISDIR(i_mode) &&
	321	!S_ISLNK(i_mode))
	322	goto out_put;
	323
7a0ad10c CH	324	mapping = file->f_mapping;
	325	if (!mapping) {
	326	ret = -EINVAL;
	327	goto out_put;
	328	}
	329
	330	ret = 0;
	331	if (flags & SYNC_FILE_RANGE_WAIT_BEFORE) {
	332	ret = filemap_fdatawait_range(mapping, offset, endbyte);
	333	if (ret < 0)
	334	goto out_put;
	335	}
	336
	337	if (flags & SYNC_FILE_RANGE_WRITE) {
	338	ret = filemap_fdatawrite_range(mapping, offset, endbyte);
	339	if (ret < 0)
	340	goto out_put;
	341	}
	342
	343	if (flags & SYNC_FILE_RANGE_WAIT_AFTER)
	344	ret = filemap_fdatawait_range(mapping, offset, endbyte);
	345
f79e2abb AM	346	out_put:
	347	fput_light(file, fput_needed);
	348	out:
	349	return ret;
	350	}
6673e0c3 HC	351	#ifdef CONFIG_HAVE_SYSCALL_WRAPPERS
	352	asmlinkage long SyS_sync_file_range(long fd, loff_t offset, loff_t nbytes,
	353	long flags)
	354	{
	355	return SYSC_sync_file_range((int) fd, offset, nbytes,
	356	(unsigned int) flags);
	357	}
	358	SYSCALL_ALIAS(sys_sync_file_range, SyS_sync_file_range);
	359	#endif
f79e2abb	360
edd5cd4a DW	361	/* It would be nice if people remember that not all the world's an i386
edd5cd4a DW	362	when they introduce new system calls */
6673e0c3 HC	363	SYSCALL_DEFINE(sync_file_range2)(int fd, unsigned int flags,
6673e0c3 HC	364	loff_t offset, loff_t nbytes)
edd5cd4a DW	365	{
	366	return sys_sync_file_range(fd, offset, nbytes, flags);
	367	}
6673e0c3 HC	368	#ifdef CONFIG_HAVE_SYSCALL_WRAPPERS
	369	asmlinkage long SyS_sync_file_range2(long fd, long flags,
	370	loff_t offset, loff_t nbytes)
	371	{
	372	return SYSC_sync_file_range2((int) fd, (unsigned int) flags,
	373	offset, nbytes);
	374	}
	375	SYSCALL_ALIAS(sys_sync_file_range2, SyS_sync_file_range2);
	376	#endif