예제 #1
0
struct vnode *
vn_initialize(
	struct inode	*inode)
{
	struct vnode	*vp = LINVFS_GET_VP(inode);

	XFS_STATS_INC(vn_active);
	XFS_STATS_INC(vn_alloc);

	vp->v_flag = VMODIFIED;
	spinlock_init(&vp->v_lock, "v_lock");

	spin_lock(&vnumber_lock);
	if (!++vn_generation)	/* v_number shouldn't be zero */
		vn_generation++;
	vp->v_number = vn_generation;
	spin_unlock(&vnumber_lock);

	ASSERT(VN_CACHED(vp) == 0);

	/* Initialize the first behavior and the behavior chain head. */
	vn_bhv_head_init(VN_BHV_HEAD(vp), "vnode");

#ifdef	XFS_VNODE_TRACE
	vp->v_trace = ktrace_alloc(VNODE_TRACE_SIZE, KM_SLEEP);
#endif	/* XFS_VNODE_TRACE */

	vn_trace_exit(vp, "vn_initialize", (inst_t *)__return_address);
	return vp;
}
예제 #2
0
/*
 * Test whether it is appropriate to check an inode for and free post EOF
 * blocks. The 'force' parameter determines whether we should also consider
 * regular files that are marked preallocated or append-only.
 */
bool
xfs_can_free_eofblocks(struct xfs_inode *ip, bool force)
{
	/* prealloc/delalloc exists only on regular files */
	if (!S_ISREG(ip->i_d.di_mode))
		return false;

	/*
	 * Zero sized files with no cached pages and delalloc blocks will not
	 * have speculative prealloc/delalloc blocks to remove.
	 */
	if (VFS_I(ip)->i_size == 0 &&
	    VN_CACHED(VFS_I(ip)) == 0 &&
	    ip->i_delayed_blks == 0)
		return false;

	/* If we haven't read in the extent list, then don't do it now. */
	if (!(ip->i_df.if_flags & XFS_IFEXTENTS))
		return false;

	/*
	 * Do not free real preallocated or append-only files unless the file
	 * has delalloc blocks and we are forced to remove them.
	 */
	if (ip->i_d.di_flags & (XFS_DIFLAG_PREALLOC | XFS_DIFLAG_APPEND))
		if (!force || ip->i_delayed_blks == 0)
			return false;

	return true;
}
예제 #3
0
/*
 * vnode pcache layer for vnode_tosspages.
 * 'last' parameter unused but left in for IRIX compatibility
 */
void
fs_tosspages(
	bhv_desc_t	*bdp,
	xfs_off_t	first,
	xfs_off_t	last,
	int		fiopt)
{
	vnode_t		*vp = BHV_TO_VNODE(bdp);
	struct inode	*ip = LINVFS_GET_IP(vp);

	if (VN_CACHED(vp))
		truncate_inode_pages(ip->i_mapping, first);
}
예제 #4
0
/*
 * xfs_inval_cached_pages
 * 
 * This routine is responsible for keeping direct I/O and buffered I/O
 * somewhat coherent.  From here we make sure that we're at least
 * temporarily holding the inode I/O lock exclusively and then call
 * the page cache to flush and invalidate any cached pages.  If there
 * are no cached pages this routine will be very quick.
 */
void
xfs_inval_cached_pages(
	vnode_t		*vp,
	xfs_iocore_t	*io,
	xfs_off_t	offset,
	int		write,
	int		relock)
{
	if (VN_CACHED(vp)) {
		xfs_inval_cached_trace(io, offset, -1, ctooff(offtoct(offset)), -1);
		VOP_FLUSHINVAL_PAGES(vp, ctooff(offtoct(offset)), -1, FI_REMAPF_LOCKED);
	}

}
예제 #5
0
/*
 * vnode pcache layer for vnode_flushinval_pages.
 * 'last' parameter unused but left in for IRIX compatibility
 */
void
fs_flushinval_pages(
	bhv_desc_t	*bdp,
	xfs_off_t	first,
	xfs_off_t	last,
	int		fiopt)
{
	vnode_t		*vp = BHV_TO_VNODE(bdp);
	struct inode	*ip = LINVFS_GET_IP(vp);

	if (VN_CACHED(vp)) {
		filemap_fdatasync(ip->i_mapping);
		fsync_inode_data_buffers(ip);
		filemap_fdatawait(ip->i_mapping);

		truncate_inode_pages(ip->i_mapping, first);
	}
}
예제 #6
0
/*
 * xfs_inval_cached_pages
 * 
 * This routine is responsible for keeping direct I/O and buffered I/O
 * somewhat coherent.  From here we make sure that we're at least
 * temporarily holding the inode I/O lock exclusively and then call
 * the page cache to flush and invalidate any cached pages.  If there
 * are no cached pages this routine will be very quick.
 */
void
xfs_inval_cached_pages(
	vnode_t		*vp,
	xfs_iocore_t	*io,
	xfs_off_t	offset,
	int		write,
	int		relock)
{
	xfs_mount_t	*mp;

	if (!VN_CACHED(vp)) {
		return;
	}

	mp = io->io_mount;

	/*
	 * We need to get the I/O lock exclusively in order
	 * to safely invalidate pages and mappings.
	 */
	if (relock) {
		XFS_IUNLOCK(mp, io, XFS_IOLOCK_SHARED);
		XFS_ILOCK(mp, io, XFS_IOLOCK_EXCL);
	}

	/* Writing beyond EOF creates a hole that must be zeroed */
	if (write && (offset > XFS_SIZE(mp, io))) {
		xfs_fsize_t	isize;

		XFS_ILOCK(mp, io, XFS_ILOCK_EXCL|XFS_EXTSIZE_RD);
		isize = XFS_SIZE(mp, io);
		if (offset > isize) {
			xfs_zero_eof(vp, io, offset, isize, offset);
		}
		XFS_IUNLOCK(mp, io, XFS_ILOCK_EXCL|XFS_EXTSIZE_RD);
	}

	xfs_inval_cached_trace(io, offset, -1, ctooff(offtoct(offset)), -1);
	VOP_FLUSHINVAL_PAGES(vp, ctooff(offtoct(offset)), -1, FI_REMAPF_LOCKED);
	if (relock) {
		XFS_ILOCK_DEMOTE(mp, io, XFS_IOLOCK_EXCL);
	}
}
예제 #7
0
/*
 * vnode pcache layer for vnode_flush_pages.
 * 'last' parameter unused but left in for IRIX compatibility
 */
int
fs_flush_pages(
	bhv_desc_t	*bdp,
	xfs_off_t	first,
	xfs_off_t	last,
	uint64_t	flags,
	int		fiopt)
{
	vnode_t		*vp = BHV_TO_VNODE(bdp);
	struct inode	*ip = LINVFS_GET_IP(vp);

	if (VN_CACHED(vp)) {
		filemap_fdatasync(ip->i_mapping);
		fsync_inode_data_buffers(ip);
		filemap_fdatawait(ip->i_mapping);
	}

	return 0;
}
예제 #8
0
int
xfs_swap_extents(
	xfs_inode_t	*ip,	/* target inode */
	xfs_inode_t	*tip,	/* tmp inode */
	xfs_swapext_t	*sxp)
{
	xfs_mount_t	*mp = ip->i_mount;
	xfs_trans_t	*tp;
	xfs_bstat_t	*sbp = &sxp->sx_stat;
	xfs_ifork_t	*tempifp, *ifp, *tifp;
	int		src_log_flags, target_log_flags;
	int		error = 0;
	int		aforkblks = 0;
	int		taforkblks = 0;
	__uint64_t	tmp;

	tempifp = kmem_alloc(sizeof(xfs_ifork_t), KM_MAYFAIL);
	if (!tempifp) {
		error = XFS_ERROR(ENOMEM);
		goto out;
	}

	/*
	 * we have to do two separate lock calls here to keep lockdep
	 * happy. If we try to get all the locks in one call, lock will
	 * report false positives when we drop the ILOCK and regain them
	 * below.
	 */
	xfs_lock_two_inodes(ip, tip, XFS_IOLOCK_EXCL);
	xfs_lock_two_inodes(ip, tip, XFS_ILOCK_EXCL);

	/* Verify that both files have the same format */
	if ((ip->i_d.di_mode & S_IFMT) != (tip->i_d.di_mode & S_IFMT)) {
		error = XFS_ERROR(EINVAL);
		goto out_unlock;
	}

	/* Verify both files are either real-time or non-realtime */
	if (XFS_IS_REALTIME_INODE(ip) != XFS_IS_REALTIME_INODE(tip)) {
		error = XFS_ERROR(EINVAL);
		goto out_unlock;
	}

	error = -filemap_write_and_wait(VFS_I(tip)->i_mapping);
	if (error)
		goto out_unlock;
	truncate_pagecache_range(VFS_I(tip), 0, -1);

	/* Verify O_DIRECT for ftmp */
	if (VN_CACHED(VFS_I(tip)) != 0) {
		error = XFS_ERROR(EINVAL);
		goto out_unlock;
	}

	/* Verify all data are being swapped */
	if (sxp->sx_offset != 0 ||
	    sxp->sx_length != ip->i_d.di_size ||
	    sxp->sx_length != tip->i_d.di_size) {
		error = XFS_ERROR(EFAULT);
		goto out_unlock;
	}

	trace_xfs_swap_extent_before(ip, 0);
	trace_xfs_swap_extent_before(tip, 1);

	/* check inode formats now that data is flushed */
	error = xfs_swap_extents_check_format(ip, tip);
	if (error) {
		xfs_notice(mp,
		    "%s: inode 0x%llx format is incompatible for exchanging.",
				__func__, ip->i_ino);
		goto out_unlock;
	}

	/*
	 * Compare the current change & modify times with that
	 * passed in.  If they differ, we abort this swap.
	 * This is the mechanism used to ensure the calling
	 * process that the file was not changed out from
	 * under it.
	 */
	if ((sbp->bs_ctime.tv_sec != VFS_I(ip)->i_ctime.tv_sec) ||
	    (sbp->bs_ctime.tv_nsec != VFS_I(ip)->i_ctime.tv_nsec) ||
	    (sbp->bs_mtime.tv_sec != VFS_I(ip)->i_mtime.tv_sec) ||
	    (sbp->bs_mtime.tv_nsec != VFS_I(ip)->i_mtime.tv_nsec)) {
		error = XFS_ERROR(EBUSY);
		goto out_unlock;
	}

	/* We need to fail if the file is memory mapped.  Once we have tossed
	 * all existing pages, the page fault will have no option
	 * but to go to the filesystem for pages. By making the page fault call
	 * vop_read (or write in the case of autogrow) they block on the iolock
	 * until we have switched the extents.
	 */
	if (VN_MAPPED(VFS_I(ip))) {
		error = XFS_ERROR(EBUSY);
		goto out_unlock;
	}

	xfs_iunlock(ip, XFS_ILOCK_EXCL);
	xfs_iunlock(tip, XFS_ILOCK_EXCL);

	/*
	 * There is a race condition here since we gave up the
	 * ilock.  However, the data fork will not change since
	 * we have the iolock (locked for truncation too) so we
	 * are safe.  We don't really care if non-io related
	 * fields change.
	 */
	truncate_pagecache_range(VFS_I(ip), 0, -1);

	tp = xfs_trans_alloc(mp, XFS_TRANS_SWAPEXT);
	error = xfs_trans_reserve(tp, &M_RES(mp)->tr_ichange, 0, 0);
	if (error) {
		xfs_iunlock(ip,  XFS_IOLOCK_EXCL);
		xfs_iunlock(tip, XFS_IOLOCK_EXCL);
		xfs_trans_cancel(tp, 0);
		goto out;
	}
	xfs_lock_two_inodes(ip, tip, XFS_ILOCK_EXCL);

	/*
	 * Count the number of extended attribute blocks
	 */
	if ( ((XFS_IFORK_Q(ip) != 0) && (ip->i_d.di_anextents > 0)) &&
	     (ip->i_d.di_aformat != XFS_DINODE_FMT_LOCAL)) {
		error = xfs_bmap_count_blocks(tp, ip, XFS_ATTR_FORK, &aforkblks);
		if (error)
			goto out_trans_cancel;
	}
	if ( ((XFS_IFORK_Q(tip) != 0) && (tip->i_d.di_anextents > 0)) &&
	     (tip->i_d.di_aformat != XFS_DINODE_FMT_LOCAL)) {
		error = xfs_bmap_count_blocks(tp, tip, XFS_ATTR_FORK,
			&taforkblks);
		if (error)
			goto out_trans_cancel;
	}

	xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL);
	xfs_trans_ijoin(tp, tip, XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL);

	/*
	 * Before we've swapped the forks, lets set the owners of the forks
	 * appropriately. We have to do this as we are demand paging the btree
	 * buffers, and so the validation done on read will expect the owner
	 * field to be correctly set. Once we change the owners, we can swap the
	 * inode forks.
	 *
	 * Note the trickiness in setting the log flags - we set the owner log
	 * flag on the opposite inode (i.e. the inode we are setting the new
	 * owner to be) because once we swap the forks and log that, log
	 * recovery is going to see the fork as owned by the swapped inode,
	 * not the pre-swapped inodes.
	 */
	src_log_flags = XFS_ILOG_CORE;
	target_log_flags = XFS_ILOG_CORE;
	if (ip->i_d.di_version == 3 &&
	    ip->i_d.di_format == XFS_DINODE_FMT_BTREE) {
		target_log_flags |= XFS_ILOG_DOWNER;
		error = xfs_bmbt_change_owner(tp, ip, XFS_DATA_FORK,
					      tip->i_ino, NULL);
		if (error)
			goto out_trans_cancel;
	}

	if (tip->i_d.di_version == 3 &&
	    tip->i_d.di_format == XFS_DINODE_FMT_BTREE) {
		src_log_flags |= XFS_ILOG_DOWNER;
		error = xfs_bmbt_change_owner(tp, tip, XFS_DATA_FORK,
					      ip->i_ino, NULL);
		if (error)
			goto out_trans_cancel;
	}

	/*
	 * Swap the data forks of the inodes
	 */
	ifp = &ip->i_df;
	tifp = &tip->i_df;
	*tempifp = *ifp;	/* struct copy */
	*ifp = *tifp;		/* struct copy */
	*tifp = *tempifp;	/* struct copy */

	/*
	 * Fix the on-disk inode values
	 */
	tmp = (__uint64_t)ip->i_d.di_nblocks;
	ip->i_d.di_nblocks = tip->i_d.di_nblocks - taforkblks + aforkblks;
	tip->i_d.di_nblocks = tmp + taforkblks - aforkblks;

	tmp = (__uint64_t) ip->i_d.di_nextents;
	ip->i_d.di_nextents = tip->i_d.di_nextents;
	tip->i_d.di_nextents = tmp;

	tmp = (__uint64_t) ip->i_d.di_format;
	ip->i_d.di_format = tip->i_d.di_format;
	tip->i_d.di_format = tmp;

	/*
	 * The extents in the source inode could still contain speculative
	 * preallocation beyond EOF (e.g. the file is open but not modified
	 * while defrag is in progress). In that case, we need to copy over the
	 * number of delalloc blocks the data fork in the source inode is
	 * tracking beyond EOF so that when the fork is truncated away when the
	 * temporary inode is unlinked we don't underrun the i_delayed_blks
	 * counter on that inode.
	 */
	ASSERT(tip->i_delayed_blks == 0);
	tip->i_delayed_blks = ip->i_delayed_blks;
	ip->i_delayed_blks = 0;

	switch (ip->i_d.di_format) {
	case XFS_DINODE_FMT_EXTENTS:
		/* If the extents fit in the inode, fix the
		 * pointer.  Otherwise it's already NULL or
		 * pointing to the extent.
		 */
		if (ip->i_d.di_nextents <= XFS_INLINE_EXTS) {
			ifp->if_u1.if_extents =
				ifp->if_u2.if_inline_ext;
		}
		src_log_flags |= XFS_ILOG_DEXT;
		break;
	case XFS_DINODE_FMT_BTREE:
		ASSERT(ip->i_d.di_version < 3 ||
		       (src_log_flags & XFS_ILOG_DOWNER));
		src_log_flags |= XFS_ILOG_DBROOT;
		break;
	}

	switch (tip->i_d.di_format) {
	case XFS_DINODE_FMT_EXTENTS:
		/* If the extents fit in the inode, fix the
		 * pointer.  Otherwise it's already NULL or
		 * pointing to the extent.
		 */
		if (tip->i_d.di_nextents <= XFS_INLINE_EXTS) {
			tifp->if_u1.if_extents =
				tifp->if_u2.if_inline_ext;
		}
		target_log_flags |= XFS_ILOG_DEXT;
		break;
	case XFS_DINODE_FMT_BTREE:
		target_log_flags |= XFS_ILOG_DBROOT;
		ASSERT(tip->i_d.di_version < 3 ||
		       (target_log_flags & XFS_ILOG_DOWNER));
		break;
	}

	xfs_trans_log_inode(tp, ip,  src_log_flags);
	xfs_trans_log_inode(tp, tip, target_log_flags);

	/*
	 * If this is a synchronous mount, make sure that the
	 * transaction goes to disk before returning to the user.
	 */
	if (mp->m_flags & XFS_MOUNT_WSYNC)
		xfs_trans_set_sync(tp);

	error = xfs_trans_commit(tp, 0);

	trace_xfs_swap_extent_after(ip, 0);
	trace_xfs_swap_extent_after(tip, 1);
out:
	kmem_free(tempifp);
	return error;

out_unlock:
	xfs_iunlock(ip,  XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL);
	xfs_iunlock(tip, XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL);
	goto out;

out_trans_cancel:
	xfs_trans_cancel(tp, 0);
	goto out_unlock;
}
예제 #9
0
ssize_t				/* bytes written, or (-) error */
xfs_write(
	bhv_desc_t		*bdp,
	struct kiocb		*iocb,
	const struct iovec	*iovp,
	unsigned int		nsegs,
	loff_t			*offset,
	int			ioflags,
	cred_t			*credp)
{
	struct file		*file = iocb->ki_filp;
	struct address_space	*mapping = file->f_mapping;
	struct inode		*inode = mapping->host;
	unsigned long		segs = nsegs;
	xfs_inode_t		*xip;
	xfs_mount_t		*mp;
	ssize_t			ret = 0, error = 0;
	xfs_fsize_t		isize, new_size;
	xfs_iocore_t		*io;
	vnode_t			*vp;
	unsigned long		seg;
	int			iolock;
	int			eventsent = 0;
	vrwlock_t		locktype;
	size_t			ocount = 0, count;
	loff_t			pos;
	int			need_isem = 1, need_flush = 0;

	XFS_STATS_INC(xs_write_calls);

	vp = BHV_TO_VNODE(bdp);
	xip = XFS_BHVTOI(bdp);

	for (seg = 0; seg < segs; seg++) {
		const struct iovec *iv = &iovp[seg];

		/*
		 * If any segment has a negative length, or the cumulative
		 * length ever wraps negative then return -EINVAL.
		 */
		ocount += iv->iov_len;
		if (unlikely((ssize_t)(ocount|iv->iov_len) < 0))
			return -EINVAL;
		if (access_ok(VERIFY_READ, iv->iov_base, iv->iov_len))
			continue;
		if (seg == 0)
			return -EFAULT;
		segs = seg;
		ocount -= iv->iov_len;  /* This segment is no good */
		break;
	}

	count = ocount;
	pos = *offset;

	if (count == 0)
		return 0;

	io = &xip->i_iocore;
	mp = io->io_mount;

	if (XFS_FORCED_SHUTDOWN(mp))
		return -EIO;

	if (ioflags & IO_ISDIRECT) {
		xfs_buftarg_t	*target =
			(xip->i_d.di_flags & XFS_DIFLAG_REALTIME) ?
				mp->m_rtdev_targp : mp->m_ddev_targp;

		if ((pos & target->pbr_smask) || (count & target->pbr_smask))
			return XFS_ERROR(-EINVAL);

		if (!VN_CACHED(vp) && pos < i_size_read(inode))
			need_isem = 0;

		if (VN_CACHED(vp))
			need_flush = 1;
	}

relock:
	if (need_isem) {
		iolock = XFS_IOLOCK_EXCL;
		locktype = VRWLOCK_WRITE;

		down(&inode->i_sem);
	} else {
		iolock = XFS_IOLOCK_SHARED;
		locktype = VRWLOCK_WRITE_DIRECT;
	}

	xfs_ilock(xip, XFS_ILOCK_EXCL|iolock);

	isize = i_size_read(inode);

	if (file->f_flags & O_APPEND)
		*offset = isize;

start:
	error = -generic_write_checks(file, &pos, &count,
					S_ISBLK(inode->i_mode));
	if (error) {
		xfs_iunlock(xip, XFS_ILOCK_EXCL|iolock);
		goto out_unlock_isem;
	}

	new_size = pos + count;
	if (new_size > isize)
		io->io_new_size = new_size;

	if ((DM_EVENT_ENABLED(vp->v_vfsp, xip, DM_EVENT_WRITE) &&
	    !(ioflags & IO_INVIS) && !eventsent)) {
		loff_t		savedsize = pos;
		int		dmflags = FILP_DELAY_FLAG(file);

		if (need_isem)
			dmflags |= DM_FLAGS_ISEM;

		xfs_iunlock(xip, XFS_ILOCK_EXCL);
		error = XFS_SEND_DATA(xip->i_mount, DM_EVENT_WRITE, vp,
				      pos, count,
				      dmflags, &locktype);
		if (error) {
			xfs_iunlock(xip, iolock);
			goto out_unlock_isem;
		}
		xfs_ilock(xip, XFS_ILOCK_EXCL);
		eventsent = 1;

		/*
		 * The iolock was dropped and reaquired in XFS_SEND_DATA
		 * so we have to recheck the size when appending.
		 * We will only "goto start;" once, since having sent the
		 * event prevents another call to XFS_SEND_DATA, which is
		 * what allows the size to change in the first place.
		 */
		if ((file->f_flags & O_APPEND) && savedsize != isize) {
			pos = isize = xip->i_d.di_size;
			goto start;
		}
	}

	/*
	 * On Linux, generic_file_write updates the times even if
	 * no data is copied in so long as the write had a size.
	 *
	 * We must update xfs' times since revalidate will overcopy xfs.
	 */
	if (!(ioflags & IO_INVIS)) {
		xfs_ichgtime(xip, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
		inode_update_time(inode, 1);
	}

	/*
	 * If the offset is beyond the size of the file, we have a couple
	 * of things to do. First, if there is already space allocated
	 * we need to either create holes or zero the disk or ...
	 *
	 * If there is a page where the previous size lands, we need
	 * to zero it out up to the new size.
	 */

	if (pos > isize) {
		error = xfs_zero_eof(BHV_TO_VNODE(bdp), io, pos,
					isize, pos + count);
		if (error) {
			xfs_iunlock(xip, XFS_ILOCK_EXCL|iolock);
			goto out_unlock_isem;
		}
	}
	xfs_iunlock(xip, XFS_ILOCK_EXCL);

	/*
	 * If we're writing the file then make sure to clear the
	 * setuid and setgid bits if the process is not being run
	 * by root.  This keeps people from modifying setuid and
	 * setgid binaries.
	 */

	if (((xip->i_d.di_mode & S_ISUID) ||
	    ((xip->i_d.di_mode & (S_ISGID | S_IXGRP)) ==
		(S_ISGID | S_IXGRP))) &&
	     !capable(CAP_FSETID)) {
		error = xfs_write_clear_setuid(xip);
		if (likely(!error))
			error = -remove_suid(file->f_dentry);
		if (unlikely(error)) {
			xfs_iunlock(xip, iolock);
			goto out_unlock_isem;
		}
	}

retry:
	/* We can write back this queue in page reclaim */
	current->backing_dev_info = mapping->backing_dev_info;

	if ((ioflags & IO_ISDIRECT)) {
		if (need_flush) {
			xfs_inval_cached_trace(io, pos, -1,
					ctooff(offtoct(pos)), -1);
			VOP_FLUSHINVAL_PAGES(vp, ctooff(offtoct(pos)),
					-1, FI_REMAPF_LOCKED);
		}

		if (need_isem) {
			/* demote the lock now the cached pages are gone */
			XFS_ILOCK_DEMOTE(mp, io, XFS_IOLOCK_EXCL);
			up(&inode->i_sem);

			iolock = XFS_IOLOCK_SHARED;
			locktype = VRWLOCK_WRITE_DIRECT;
			need_isem = 0;
		}

 		xfs_rw_enter_trace(XFS_DIOWR_ENTER, io, (void *)iovp, segs,
				*offset, ioflags);
		ret = generic_file_direct_write(iocb, iovp,
				&segs, pos, offset, count, ocount);

		/*
		 * direct-io write to a hole: fall through to buffered I/O
		 * for completing the rest of the request.
		 */
		if (ret >= 0 && ret != count) {
			XFS_STATS_ADD(xs_write_bytes, ret);

			pos += ret;
			count -= ret;

			need_isem = 1;
			ioflags &= ~IO_ISDIRECT;
			xfs_iunlock(xip, iolock);
			goto relock;
		}
	} else {
		xfs_rw_enter_trace(XFS_WRITE_ENTER, io, (void *)iovp, segs,
				*offset, ioflags);
		ret = generic_file_buffered_write(iocb, iovp, segs,
				pos, offset, count, ret);
	}

	current->backing_dev_info = NULL;

	if (ret == -EIOCBQUEUED)
		ret = wait_on_sync_kiocb(iocb);

	if ((ret == -ENOSPC) &&
	    DM_EVENT_ENABLED(vp->v_vfsp, xip, DM_EVENT_NOSPACE) &&
	    !(ioflags & IO_INVIS)) {

		xfs_rwunlock(bdp, locktype);
		error = XFS_SEND_NAMESP(xip->i_mount, DM_EVENT_NOSPACE, vp,
				DM_RIGHT_NULL, vp, DM_RIGHT_NULL, NULL, NULL,
				0, 0, 0); /* Delay flag intentionally  unused */
		if (error)
			goto out_unlock_isem;
		xfs_rwlock(bdp, locktype);
		pos = xip->i_d.di_size;
		goto retry;
	}

	if (*offset > xip->i_d.di_size) {
		xfs_ilock(xip, XFS_ILOCK_EXCL);
		if (*offset > xip->i_d.di_size) {
			xip->i_d.di_size = *offset;
			i_size_write(inode, *offset);
			xip->i_update_core = 1;
			xip->i_update_size = 1;
		}
		xfs_iunlock(xip, XFS_ILOCK_EXCL);
	}

	error = -ret;
	if (ret <= 0)
		goto out_unlock_internal;

	XFS_STATS_ADD(xs_write_bytes, ret);

	/* Handle various SYNC-type writes */
	if ((file->f_flags & O_SYNC) || IS_SYNC(inode)) {
		/*
		 * If we're treating this as O_DSYNC and we have not updated the
		 * size, force the log.
		 */
		if (!(mp->m_flags & XFS_MOUNT_OSYNCISOSYNC) &&
		    !(xip->i_update_size)) {
			xfs_inode_log_item_t	*iip = xip->i_itemp;

			/*
			 * If an allocation transaction occurred
			 * without extending the size, then we have to force
			 * the log up the proper point to ensure that the
			 * allocation is permanent.  We can't count on
			 * the fact that buffered writes lock out direct I/O
			 * writes - the direct I/O write could have extended
			 * the size nontransactionally, then finished before
			 * we started.  xfs_write_file will think that the file
			 * didn't grow but the update isn't safe unless the
			 * size change is logged.
			 *
			 * Force the log if we've committed a transaction
			 * against the inode or if someone else has and
			 * the commit record hasn't gone to disk (e.g.
			 * the inode is pinned).  This guarantees that
			 * all changes affecting the inode are permanent
			 * when we return.
			 */
			if (iip && iip->ili_last_lsn) {
				xfs_log_force(mp, iip->ili_last_lsn,
						XFS_LOG_FORCE | XFS_LOG_SYNC);
			} else if (xfs_ipincount(xip) > 0) {
				xfs_log_force(mp, (xfs_lsn_t)0,
						XFS_LOG_FORCE | XFS_LOG_SYNC);
			}

		} else {
			xfs_trans_t	*tp;

			/*
			 * O_SYNC or O_DSYNC _with_ a size update are handled
			 * the same way.
			 *
			 * If the write was synchronous then we need to make
			 * sure that the inode modification time is permanent.
			 * We'll have updated the timestamp above, so here
			 * we use a synchronous transaction to log the inode.
			 * It's not fast, but it's necessary.
			 *
			 * If this a dsync write and the size got changed
			 * non-transactionally, then we need to ensure that
			 * the size change gets logged in a synchronous
			 * transaction.
			 */

			tp = xfs_trans_alloc(mp, XFS_TRANS_WRITE_SYNC);
			if ((error = xfs_trans_reserve(tp, 0,
						      XFS_SWRITE_LOG_RES(mp),
						      0, 0, 0))) {
				/* Transaction reserve failed */
				xfs_trans_cancel(tp, 0);
			} else {
				/* Transaction reserve successful */
				xfs_ilock(xip, XFS_ILOCK_EXCL);
				xfs_trans_ijoin(tp, xip, XFS_ILOCK_EXCL);
				xfs_trans_ihold(tp, xip);
				xfs_trans_log_inode(tp, xip, XFS_ILOG_CORE);
				xfs_trans_set_sync(tp);
				error = xfs_trans_commit(tp, 0, NULL);
				xfs_iunlock(xip, XFS_ILOCK_EXCL);
				if (error)
					goto out_unlock_internal;
			}
		}
	
		xfs_rwunlock(bdp, locktype);
		if (need_isem)
			up(&inode->i_sem);

		error = sync_page_range(inode, mapping, pos, ret);
		if (!error)
			error = ret;
		return error;
	}

 out_unlock_internal:
	xfs_rwunlock(bdp, locktype);
 out_unlock_isem:
	if (need_isem)
		up(&inode->i_sem);
	return -error;
}
예제 #10
0
ssize_t			/* bytes read, or (-)  error */
xfs_read(
	bhv_desc_t		*bdp,
	struct kiocb		*iocb,
	const struct iovec	*iovp,
	unsigned int		segs,
	loff_t			*offset,
	int			ioflags,
	cred_t			*credp)
{
	struct file		*file = iocb->ki_filp;
	struct inode		*inode = file->f_mapping->host;
	size_t			size = 0;
	ssize_t			ret;
	xfs_fsize_t		n;
	xfs_inode_t		*ip;
	xfs_mount_t		*mp;
	vnode_t			*vp;
	unsigned long		seg;

	ip = XFS_BHVTOI(bdp);
	vp = BHV_TO_VNODE(bdp);
	mp = ip->i_mount;

	XFS_STATS_INC(xs_read_calls);

	/* START copy & waste from filemap.c */
	for (seg = 0; seg < segs; seg++) {
		const struct iovec *iv = &iovp[seg];

		/*
		 * If any segment has a negative length, or the cumulative
		 * length ever wraps negative then return -EINVAL.
		 */
		size += iv->iov_len;
		if (unlikely((ssize_t)(size|iv->iov_len) < 0))
			return XFS_ERROR(-EINVAL);
	}
	/* END copy & waste from filemap.c */

	if (unlikely(ioflags & IO_ISDIRECT)) {
		xfs_buftarg_t	*target =
			(ip->i_d.di_flags & XFS_DIFLAG_REALTIME) ?
				mp->m_rtdev_targp : mp->m_ddev_targp;
		if ((*offset & target->bt_smask) ||
		    (size & target->bt_smask)) {
			if (*offset == ip->i_d.di_size) {
				return (0);
			}
			return -XFS_ERROR(EINVAL);
		}
	}

	n = XFS_MAXIOFFSET(mp) - *offset;
	if ((n <= 0) || (size == 0))
		return 0;

	if (n < size)
		size = n;

	if (XFS_FORCED_SHUTDOWN(mp))
		return -EIO;

	if (unlikely(ioflags & IO_ISDIRECT))
		mutex_lock(&inode->i_mutex);
	xfs_ilock(ip, XFS_IOLOCK_SHARED);

	if (DM_EVENT_ENABLED(vp->v_vfsp, ip, DM_EVENT_READ) &&
	    !(ioflags & IO_INVIS)) {
		vrwlock_t locktype = VRWLOCK_READ;
		int dmflags = FILP_DELAY_FLAG(file) | DM_SEM_FLAG_RD(ioflags);

		ret = -XFS_SEND_DATA(mp, DM_EVENT_READ,
					BHV_TO_VNODE(bdp), *offset, size,
					dmflags, &locktype);
		if (ret) {
			xfs_iunlock(ip, XFS_IOLOCK_SHARED);
			goto unlock_mutex;
		}
	}

	if (unlikely((ioflags & IO_ISDIRECT) && VN_CACHED(vp)))
		VOP_FLUSHINVAL_PAGES(vp, ctooff(offtoct(*offset)),
						-1, FI_REMAPF_LOCKED);

	xfs_rw_enter_trace(XFS_READ_ENTER, &ip->i_iocore,
				(void *)iovp, segs, *offset, ioflags);
	ret = __generic_file_aio_read(iocb, iovp, segs, offset);
	if (ret == -EIOCBQUEUED && !(ioflags & IO_ISAIO))
		ret = wait_on_sync_kiocb(iocb);
	if (ret > 0)
		XFS_STATS_ADD(xs_read_bytes, ret);

	xfs_iunlock(ip, XFS_IOLOCK_SHARED);

unlock_mutex:
	if (unlikely(ioflags & IO_ISDIRECT))
		mutex_unlock(&inode->i_mutex);
	return ret;
}
예제 #11
0
/*
 * Syssgi interface for swapext
 */
int
xfs_swapext(
	xfs_swapext_t	__user *sxp)
{
	xfs_swapext_t	sx;
	xfs_inode_t     *ip=NULL, *tip=NULL, *ips[2];
	xfs_trans_t     *tp;
	xfs_mount_t     *mp;
	xfs_bstat_t	*sbp;
	struct file	*fp = NULL, *tfp = NULL;
	vnode_t		*vp, *tvp;
	bhv_desc_t      *bdp, *tbdp;
	vn_bhv_head_t   *bhp, *tbhp;
	uint		lock_flags=0;
	int		ilf_fields, tilf_fields;
	int		error = 0;
	xfs_ifork_t	tempif, *ifp, *tifp;
	__uint64_t	tmp;
	int		aforkblks = 0;
	int		taforkblks = 0;
	int		locked = 0;

	if (copy_from_user(&sx, sxp, sizeof(sx)))
		return XFS_ERROR(EFAULT);

	/* Pull information for the target fd */
	if (((fp = fget((int)sx.sx_fdtarget)) == NULL) ||
	    ((vp = LINVFS_GET_VP(fp->f_dentry->d_inode)) == NULL))  {
		error = XFS_ERROR(EINVAL);
		goto error0;
	}

	bhp = VN_BHV_HEAD(vp);
	bdp = vn_bhv_lookup(bhp, &xfs_vnodeops);
	if (bdp == NULL) {
		error = XFS_ERROR(EBADF);
		goto error0;
	} else {
		ip = XFS_BHVTOI(bdp);
	}

	if (((tfp = fget((int)sx.sx_fdtmp)) == NULL) ||
	    ((tvp = LINVFS_GET_VP(tfp->f_dentry->d_inode)) == NULL)) {
		error = XFS_ERROR(EINVAL);
		goto error0;
	}

	tbhp = VN_BHV_HEAD(tvp);
	tbdp = vn_bhv_lookup(tbhp, &xfs_vnodeops);
	if (tbdp == NULL) {
		error = XFS_ERROR(EBADF);
		goto error0;
	} else {
		tip = XFS_BHVTOI(tbdp);
	}

	if (ip->i_mount != tip->i_mount) {
		error =  XFS_ERROR(EINVAL);
		goto error0;
	}

	if (ip->i_ino == tip->i_ino) {
		error =  XFS_ERROR(EINVAL);
		goto error0;
	}

	mp = ip->i_mount;

	sbp = &sx.sx_stat;

	if (XFS_FORCED_SHUTDOWN(mp)) {
		error =  XFS_ERROR(EIO);
		goto error0;
	}

	locked = 1;

	/* Lock in i_ino order */
	if (ip->i_ino < tip->i_ino) {
		ips[0] = ip;
		ips[1] = tip;
	} else {
		ips[0] = tip;
		ips[1] = ip;
	}
	lock_flags = XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL;
	xfs_lock_inodes(ips, 2, 0, lock_flags);

	/* Check permissions */
	error = xfs_iaccess(ip, S_IWUSR, NULL);
	if (error)
		goto error0;

	error = xfs_iaccess(tip, S_IWUSR, NULL);
	if (error)
		goto error0;

	/* Verify that both files have the same format */
	if ((ip->i_d.di_mode & S_IFMT) != (tip->i_d.di_mode & S_IFMT)) {
		error = XFS_ERROR(EINVAL);
		goto error0;
	}

	/* Verify both files are either real-time or non-realtime */
	if ((ip->i_d.di_flags & XFS_DIFLAG_REALTIME) !=
	    (tip->i_d.di_flags & XFS_DIFLAG_REALTIME)) {
		error = XFS_ERROR(EINVAL);
		goto error0;
	}

	/* Should never get a local format */
	if (ip->i_d.di_format == XFS_DINODE_FMT_LOCAL ||
	    tip->i_d.di_format == XFS_DINODE_FMT_LOCAL) {
		error = XFS_ERROR(EINVAL);
		goto error0;
	}

	if (VN_CACHED(tvp) != 0)
		xfs_inval_cached_pages(XFS_ITOV(tip), &(tip->i_iocore),
						(xfs_off_t)0, 0, 0);

	/* Verify O_DIRECT for ftmp */
	if (VN_CACHED(tvp) != 0) {
		error = XFS_ERROR(EINVAL);
		goto error0;
	}

	/* Verify all data are being swapped */
	if (sx.sx_offset != 0 ||
	    sx.sx_length != ip->i_d.di_size ||
	    sx.sx_length != tip->i_d.di_size) {
		error = XFS_ERROR(EFAULT);
		goto error0;
	}

	/*
	 * If the target has extended attributes, the tmp file
	 * must also in order to ensure the correct data fork
	 * format.
	 */
	if ( XFS_IFORK_Q(ip) != XFS_IFORK_Q(tip) ) {
		error = XFS_ERROR(EINVAL);
		goto error0;
	}

	/*
	 * Compare the current change & modify times with that
	 * passed in.  If they differ, we abort this swap.
	 * This is the mechanism used to ensure the calling
	 * process that the file was not changed out from
	 * under it.
	 */
	if ((sbp->bs_ctime.tv_sec != ip->i_d.di_ctime.t_sec) ||
	    (sbp->bs_ctime.tv_nsec != ip->i_d.di_ctime.t_nsec) ||
	    (sbp->bs_mtime.tv_sec != ip->i_d.di_mtime.t_sec) ||
	    (sbp->bs_mtime.tv_nsec != ip->i_d.di_mtime.t_nsec)) {
		error = XFS_ERROR(EBUSY);
		goto error0;
	}

	/* We need to fail if the file is memory mapped.  Once we have tossed
	 * all existing pages, the page fault will have no option
	 * but to go to the filesystem for pages. By making the page fault call
	 * VOP_READ (or write in the case of autogrow) they block on the iolock
	 * until we have switched the extents.
	 */
	if (VN_MAPPED(vp)) {
		error = XFS_ERROR(EBUSY);
		goto error0;
	}

	xfs_iunlock(ip, XFS_ILOCK_EXCL);
	xfs_iunlock(tip, XFS_ILOCK_EXCL);

	/*
	 * There is a race condition here since we gave up the
	 * ilock.  However, the data fork will not change since
	 * we have the iolock (locked for truncation too) so we
	 * are safe.  We don't really care if non-io related
	 * fields change.
	 */

	VOP_TOSS_PAGES(vp, 0, -1, FI_REMAPF);

	tp = xfs_trans_alloc(mp, XFS_TRANS_SWAPEXT);
	if ((error = xfs_trans_reserve(tp, 0,
				     XFS_ICHANGE_LOG_RES(mp), 0,
				     0, 0))) {
		xfs_iunlock(ip,  XFS_IOLOCK_EXCL);
		xfs_iunlock(tip, XFS_IOLOCK_EXCL);
		xfs_trans_cancel(tp, 0);
		return error;
	}
	xfs_lock_inodes(ips, 2, 0, XFS_ILOCK_EXCL);

	/*
	 * Count the number of extended attribute blocks
	 */
	if ( ((XFS_IFORK_Q(ip) != 0) && (ip->i_d.di_anextents > 0)) &&
	     (ip->i_d.di_aformat != XFS_DINODE_FMT_LOCAL)) {
		error = xfs_bmap_count_blocks(tp, ip, XFS_ATTR_FORK, &aforkblks);
		if (error) {
			xfs_iunlock(ip,  lock_flags);
			xfs_iunlock(tip, lock_flags);
			xfs_trans_cancel(tp, 0);
			return error;
		}
	}
	if ( ((XFS_IFORK_Q(tip) != 0) && (tip->i_d.di_anextents > 0)) &&
	     (tip->i_d.di_aformat != XFS_DINODE_FMT_LOCAL)) {
		error = xfs_bmap_count_blocks(tp, tip, XFS_ATTR_FORK,
			&taforkblks);
		if (error) {
			xfs_iunlock(ip,  lock_flags);
			xfs_iunlock(tip, lock_flags);
			xfs_trans_cancel(tp, 0);
			return error;
		}
	}

	/*
	 * Swap the data forks of the inodes
	 */
	ifp = &ip->i_df;
	tifp = &tip->i_df;
	tempif = *ifp;	/* struct copy */
	*ifp = *tifp;	/* struct copy */
	*tifp = tempif;	/* struct copy */

	/*
	 * Fix the on-disk inode values
	 */
	tmp = (__uint64_t)ip->i_d.di_nblocks;
	ip->i_d.di_nblocks = tip->i_d.di_nblocks - taforkblks + aforkblks;
	tip->i_d.di_nblocks = tmp + taforkblks - aforkblks;

	tmp = (__uint64_t) ip->i_d.di_nextents;
	ip->i_d.di_nextents = tip->i_d.di_nextents;
	tip->i_d.di_nextents = tmp;

	tmp = (__uint64_t) ip->i_d.di_format;
	ip->i_d.di_format = tip->i_d.di_format;
	tip->i_d.di_format = tmp;

	ilf_fields = XFS_ILOG_CORE;

	switch(ip->i_d.di_format) {
	case XFS_DINODE_FMT_EXTENTS:
		/* If the extents fit in the inode, fix the
		 * pointer.  Otherwise it's already NULL or
		 * pointing to the extent.
		 */
		if (ip->i_d.di_nextents <= XFS_INLINE_EXTS) {
			ifp->if_u1.if_extents =
				ifp->if_u2.if_inline_ext;
		}
		ilf_fields |= XFS_ILOG_DEXT;
		break;
	case XFS_DINODE_FMT_BTREE:
		ilf_fields |= XFS_ILOG_DBROOT;
		break;
	}

	tilf_fields = XFS_ILOG_CORE;

	switch(tip->i_d.di_format) {
	case XFS_DINODE_FMT_EXTENTS:
		/* If the extents fit in the inode, fix the
		 * pointer.  Otherwise it's already NULL or
		 * pointing to the extent.
		 */
		if (tip->i_d.di_nextents <= XFS_INLINE_EXTS) {
			tifp->if_u1.if_extents =
				tifp->if_u2.if_inline_ext;
		}
		tilf_fields |= XFS_ILOG_DEXT;
		break;
	case XFS_DINODE_FMT_BTREE:
		tilf_fields |= XFS_ILOG_DBROOT;
		break;
	}

	/*
	 * Increment vnode ref counts since xfs_trans_commit &
	 * xfs_trans_cancel will both unlock the inodes and
	 * decrement the associated ref counts.
	 */
	VN_HOLD(vp);
	VN_HOLD(tvp);

	xfs_trans_ijoin(tp, ip, lock_flags);
	xfs_trans_ijoin(tp, tip, lock_flags);

	xfs_trans_log_inode(tp, ip,  ilf_fields);
	xfs_trans_log_inode(tp, tip, tilf_fields);

	/*
	 * If this is a synchronous mount, make sure that the
	 * transaction goes to disk before returning to the user.
	 */
	if (mp->m_flags & XFS_MOUNT_WSYNC) {
		xfs_trans_set_sync(tp);
	}

	error = xfs_trans_commit(tp, XFS_TRANS_SWAPEXT, NULL);

	fput(fp);
	fput(tfp);

	return error;

 error0:
	if (locked) {
		xfs_iunlock(ip,  lock_flags);
		xfs_iunlock(tip, lock_flags);
	}

	if (fp != NULL) fput(fp);
	if (tfp != NULL) fput(tfp);

	return error;
}
예제 #12
0
int
xfs_swap_extents(
	xfs_inode_t	*ip,	/* target inode */
	xfs_inode_t	*tip,	/* tmp inode */
	xfs_swapext_t	*sxp)
{
	xfs_mount_t	*mp;
	xfs_trans_t	*tp;
	xfs_bstat_t	*sbp = &sxp->sx_stat;
	xfs_ifork_t	*tempifp, *ifp, *tifp;
	int		ilf_fields, tilf_fields;
	static uint	lock_flags = XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL;
	int		error = 0;
	int		aforkblks = 0;
	int		taforkblks = 0;
	__uint64_t	tmp;
	char		locked = 0;

	mp = ip->i_mount;

	tempifp = kmem_alloc(sizeof(xfs_ifork_t), KM_MAYFAIL);
	if (!tempifp) {
		error = XFS_ERROR(ENOMEM);
		goto error0;
	}

	sbp = &sxp->sx_stat;

	/*
	 * we have to do two separate lock calls here to keep lockdep
	 * happy. If we try to get all the locks in one call, lock will
	 * report false positives when we drop the ILOCK and regain them
	 * below.
	 */
	xfs_lock_two_inodes(ip, tip, XFS_IOLOCK_EXCL);
	xfs_lock_two_inodes(ip, tip, XFS_ILOCK_EXCL);
	locked = 1;

	/* Verify that both files have the same format */
	if ((ip->i_d.di_mode & S_IFMT) != (tip->i_d.di_mode & S_IFMT)) {
		error = XFS_ERROR(EINVAL);
		goto error0;
	}

	/* Verify both files are either real-time or non-realtime */
	if (XFS_IS_REALTIME_INODE(ip) != XFS_IS_REALTIME_INODE(tip)) {
		error = XFS_ERROR(EINVAL);
		goto error0;
	}

	if (VN_CACHED(VFS_I(tip)) != 0) {
		xfs_inval_cached_trace(tip, 0, -1, 0, -1);
		error = xfs_flushinval_pages(tip, 0, -1,
				FI_REMAPF_LOCKED);
		if (error)
			goto error0;
	}

	/* Verify O_DIRECT for ftmp */
	if (VN_CACHED(VFS_I(tip)) != 0) {
		error = XFS_ERROR(EINVAL);
		goto error0;
	}

	/* Verify all data are being swapped */
	if (sxp->sx_offset != 0 ||
	    sxp->sx_length != ip->i_d.di_size ||
	    sxp->sx_length != tip->i_d.di_size) {
		error = XFS_ERROR(EFAULT);
		goto error0;
	}

	/* check inode formats now that data is flushed */
	error = xfs_swap_extents_check_format(ip, tip);
	if (error) {
		xfs_fs_cmn_err(CE_NOTE, mp,
		    "%s: inode 0x%llx format is incompatible for exchanging.",
				__FILE__, ip->i_ino);
		goto error0;
	}

	/*
	 * Compare the current change & modify times with that
	 * passed in.  If they differ, we abort this swap.
	 * This is the mechanism used to ensure the calling
	 * process that the file was not changed out from
	 * under it.
	 */
	if ((sbp->bs_ctime.tv_sec != ip->i_d.di_ctime.t_sec) ||
	    (sbp->bs_ctime.tv_nsec != ip->i_d.di_ctime.t_nsec) ||
	    (sbp->bs_mtime.tv_sec != ip->i_d.di_mtime.t_sec) ||
	    (sbp->bs_mtime.tv_nsec != ip->i_d.di_mtime.t_nsec)) {
		error = XFS_ERROR(EBUSY);
		goto error0;
	}

	/* We need to fail if the file is memory mapped.  Once we have tossed
	 * all existing pages, the page fault will have no option
	 * but to go to the filesystem for pages. By making the page fault call
	 * vop_read (or write in the case of autogrow) they block on the iolock
	 * until we have switched the extents.
	 */
	if (VN_MAPPED(VFS_I(ip))) {
		error = XFS_ERROR(EBUSY);
		goto error0;
	}

	xfs_iunlock(ip, XFS_ILOCK_EXCL);
	xfs_iunlock(tip, XFS_ILOCK_EXCL);

	/*
	 * There is a race condition here since we gave up the
	 * ilock.  However, the data fork will not change since
	 * we have the iolock (locked for truncation too) so we
	 * are safe.  We don't really care if non-io related
	 * fields change.
	 */

	xfs_tosspages(ip, 0, -1, FI_REMAPF);

	tp = xfs_trans_alloc(mp, XFS_TRANS_SWAPEXT);
	if ((error = xfs_trans_reserve(tp, 0,
				     XFS_ICHANGE_LOG_RES(mp), 0,
				     0, 0))) {
		xfs_iunlock(ip,  XFS_IOLOCK_EXCL);
		xfs_iunlock(tip, XFS_IOLOCK_EXCL);
		xfs_trans_cancel(tp, 0);
		locked = 0;
		goto error0;
	}
	xfs_lock_two_inodes(ip, tip, XFS_ILOCK_EXCL);

	/*
	 * Count the number of extended attribute blocks
	 */
	if ( ((XFS_IFORK_Q(ip) != 0) && (ip->i_d.di_anextents > 0)) &&
	     (ip->i_d.di_aformat != XFS_DINODE_FMT_LOCAL)) {
		error = xfs_bmap_count_blocks(tp, ip, XFS_ATTR_FORK, &aforkblks);
		if (error) {
			xfs_trans_cancel(tp, 0);
			goto error0;
		}
	}
	if ( ((XFS_IFORK_Q(tip) != 0) && (tip->i_d.di_anextents > 0)) &&
	     (tip->i_d.di_aformat != XFS_DINODE_FMT_LOCAL)) {
		error = xfs_bmap_count_blocks(tp, tip, XFS_ATTR_FORK,
			&taforkblks);
		if (error) {
			xfs_trans_cancel(tp, 0);
			goto error0;
		}
	}

	/*
	 * Swap the data forks of the inodes
	 */
	ifp = &ip->i_df;
	tifp = &tip->i_df;
	*tempifp = *ifp;	/* struct copy */
	*ifp = *tifp;		/* struct copy */
	*tifp = *tempifp;	/* struct copy */

	/*
	 * Fix the in-memory data fork values that are dependent on the fork
	 * offset in the inode. We can't assume they remain the same as attr2
	 * has dynamic fork offsets.
	 */
	ifp->if_ext_max = XFS_IFORK_SIZE(ip, XFS_DATA_FORK) /
					(uint)sizeof(xfs_bmbt_rec_t);
	tifp->if_ext_max = XFS_IFORK_SIZE(tip, XFS_DATA_FORK) /
					(uint)sizeof(xfs_bmbt_rec_t);

	/*
	 * Fix the on-disk inode values
	 */
	tmp = (__uint64_t)ip->i_d.di_nblocks;
	ip->i_d.di_nblocks = tip->i_d.di_nblocks - taforkblks + aforkblks;
	tip->i_d.di_nblocks = tmp + taforkblks - aforkblks;

	tmp = (__uint64_t) ip->i_d.di_nextents;
	ip->i_d.di_nextents = tip->i_d.di_nextents;
	tip->i_d.di_nextents = tmp;

	tmp = (__uint64_t) ip->i_d.di_format;
	ip->i_d.di_format = tip->i_d.di_format;
	tip->i_d.di_format = tmp;

	ilf_fields = XFS_ILOG_CORE;

	switch(ip->i_d.di_format) {
	case XFS_DINODE_FMT_EXTENTS:
		/* If the extents fit in the inode, fix the
		 * pointer.  Otherwise it's already NULL or
		 * pointing to the extent.
		 */
		if (ip->i_d.di_nextents <= XFS_INLINE_EXTS) {
			ifp->if_u1.if_extents =
				ifp->if_u2.if_inline_ext;
		}
		ilf_fields |= XFS_ILOG_DEXT;
		break;
	case XFS_DINODE_FMT_BTREE:
		ilf_fields |= XFS_ILOG_DBROOT;
		break;
	}

	tilf_fields = XFS_ILOG_CORE;

	switch(tip->i_d.di_format) {
	case XFS_DINODE_FMT_EXTENTS:
		/* If the extents fit in the inode, fix the
		 * pointer.  Otherwise it's already NULL or
		 * pointing to the extent.
		 */
		if (tip->i_d.di_nextents <= XFS_INLINE_EXTS) {
			tifp->if_u1.if_extents =
				tifp->if_u2.if_inline_ext;
		}
		tilf_fields |= XFS_ILOG_DEXT;
		break;
	case XFS_DINODE_FMT_BTREE:
		tilf_fields |= XFS_ILOG_DBROOT;
		break;
	}


	IHOLD(ip);
	xfs_trans_ijoin(tp, ip, lock_flags);

	IHOLD(tip);
	xfs_trans_ijoin(tp, tip, lock_flags);

	xfs_trans_log_inode(tp, ip,  ilf_fields);
	xfs_trans_log_inode(tp, tip, tilf_fields);

	/*
	 * If this is a synchronous mount, make sure that the
	 * transaction goes to disk before returning to the user.
	 */
	if (mp->m_flags & XFS_MOUNT_WSYNC) {
		xfs_trans_set_sync(tp);
	}

	error = xfs_trans_commit(tp, XFS_TRANS_SWAPEXT);
	locked = 0;

 error0:
	if (locked) {
		xfs_iunlock(ip,  lock_flags);
		xfs_iunlock(tip, lock_flags);
	}
	if (tempifp != NULL)
		kmem_free(tempifp);
	return error;
}
예제 #13
0
ssize_t				/* bytes written, or (-) error */
xfs_write(
	bhv_desc_t		*bdp,
	struct kiocb		*iocb,
	const struct iovec	*iovp,
	unsigned int		nsegs,
	loff_t			*offset,
	int			ioflags,
	cred_t			*credp)
{
	struct file		*file = iocb->ki_filp;
	struct address_space	*mapping = file->f_mapping;
	struct inode		*inode = mapping->host;
	unsigned long		segs = nsegs;
	xfs_inode_t		*xip;
	xfs_mount_t		*mp;
	ssize_t			ret = 0, error = 0;
	xfs_fsize_t		isize, new_size;
	xfs_iocore_t		*io;
	bhv_vnode_t		*vp;
	unsigned long		seg;
	int			iolock;
	int			eventsent = 0;
	bhv_vrwlock_t		locktype;
	size_t			ocount = 0, count;
	loff_t			pos;
	int			need_i_mutex = 1, need_flush = 0;

	XFS_STATS_INC(xs_write_calls);

	vp = BHV_TO_VNODE(bdp);
	xip = XFS_BHVTOI(bdp);

	for (seg = 0; seg < segs; seg++) {
		const struct iovec *iv = &iovp[seg];

		/*
		 * If any segment has a negative length, or the cumulative
		 * length ever wraps negative then return -EINVAL.
		 */
		ocount += iv->iov_len;
		if (unlikely((ssize_t)(ocount|iv->iov_len) < 0))
			return -EINVAL;
		if (access_ok(VERIFY_READ, iv->iov_base, iv->iov_len))
			continue;
		if (seg == 0)
			return -EFAULT;
		segs = seg;
		ocount -= iv->iov_len;  /* This segment is no good */
		break;
	}

	count = ocount;
	pos = *offset;

	if (count == 0)
		return 0;

	io = &xip->i_iocore;
	mp = io->io_mount;

	vfs_wait_for_freeze(vp->v_vfsp, SB_FREEZE_WRITE);

	if (XFS_FORCED_SHUTDOWN(mp))
		return -EIO;

	if (ioflags & IO_ISDIRECT) {
		xfs_buftarg_t	*target =
			(xip->i_d.di_flags & XFS_DIFLAG_REALTIME) ?
				mp->m_rtdev_targp : mp->m_ddev_targp;

		if ((pos & target->bt_smask) || (count & target->bt_smask))
			return XFS_ERROR(-EINVAL);

		if (!VN_CACHED(vp) && pos < i_size_read(inode))
			need_i_mutex = 0;

		if (VN_CACHED(vp))
			need_flush = 1;
	}

relock:
	if (need_i_mutex) {
		iolock = XFS_IOLOCK_EXCL;
		locktype = VRWLOCK_WRITE;

		mutex_lock(&inode->i_mutex);
	} else {
		iolock = XFS_IOLOCK_SHARED;
		locktype = VRWLOCK_WRITE_DIRECT;
	}

	xfs_ilock(xip, XFS_ILOCK_EXCL|iolock);

	isize = i_size_read(inode);

	if (file->f_flags & O_APPEND)
		*offset = isize;

start:
	error = -generic_write_checks(file, &pos, &count,
					S_ISBLK(inode->i_mode));
	if (error) {
		xfs_iunlock(xip, XFS_ILOCK_EXCL|iolock);
		goto out_unlock_mutex;
	}

	new_size = pos + count;
	if (new_size > isize)
		io->io_new_size = new_size;

	if ((DM_EVENT_ENABLED(vp->v_vfsp, xip, DM_EVENT_WRITE) &&
	    !(ioflags & IO_INVIS) && !eventsent)) {
		loff_t		savedsize = pos;
		int		dmflags = FILP_DELAY_FLAG(file);

		if (need_i_mutex)
			dmflags |= DM_FLAGS_IMUX;

		xfs_iunlock(xip, XFS_ILOCK_EXCL);
		error = XFS_SEND_DATA(xip->i_mount, DM_EVENT_WRITE, vp,
				      pos, count,
				      dmflags, &locktype);
		if (error) {
			xfs_iunlock(xip, iolock);
			goto out_unlock_mutex;
		}
		xfs_ilock(xip, XFS_ILOCK_EXCL);
		eventsent = 1;

		/*
		 * The iolock was dropped and reacquired in XFS_SEND_DATA
		 * so we have to recheck the size when appending.
		 * We will only "goto start;" once, since having sent the
		 * event prevents another call to XFS_SEND_DATA, which is
		 * what allows the size to change in the first place.
		 */
		if ((file->f_flags & O_APPEND) && savedsize != isize) {
			pos = isize = xip->i_d.di_size;
			goto start;
		}
	}

	if (likely(!(ioflags & IO_INVIS))) {
		file_update_time(file);
		xfs_ichgtime_fast(xip, inode,
				  XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
	}

	/*
	 * If the offset is beyond the size of the file, we have a couple
	 * of things to do. First, if there is already space allocated
	 * we need to either create holes or zero the disk or ...
	 *
	 * If there is a page where the previous size lands, we need
	 * to zero it out up to the new size.
	 */

	if (pos > isize) {
		error = xfs_zero_eof(BHV_TO_VNODE(bdp), io, pos, isize);
		if (error) {
			xfs_iunlock(xip, XFS_ILOCK_EXCL|iolock);
			goto out_unlock_mutex;
		}
	}
	xfs_iunlock(xip, XFS_ILOCK_EXCL);

	/*
	 * If we're writing the file then make sure to clear the
	 * setuid and setgid bits if the process is not being run
	 * by root.  This keeps people from modifying setuid and
	 * setgid binaries.
	 */

	if (((xip->i_d.di_mode & S_ISUID) ||
	    ((xip->i_d.di_mode & (S_ISGID | S_IXGRP)) ==
		(S_ISGID | S_IXGRP))) &&
	     !capable(CAP_FSETID)) {
		error = xfs_write_clear_setuid(xip);
		if (likely(!error))
			error = -remove_suid(file->f_path.dentry);
		if (unlikely(error)) {
			xfs_iunlock(xip, iolock);
			goto out_unlock_mutex;
		}
	}

retry:
	/* We can write back this queue in page reclaim */
	current->backing_dev_info = mapping->backing_dev_info;

	if ((ioflags & IO_ISDIRECT)) {
		if (need_flush) {
			xfs_inval_cached_trace(io, pos, -1,
					ctooff(offtoct(pos)), -1);
			bhv_vop_flushinval_pages(vp, ctooff(offtoct(pos)),
					-1, FI_REMAPF_LOCKED);
		}

		if (need_i_mutex) {
			/* demote the lock now the cached pages are gone */
			XFS_ILOCK_DEMOTE(mp, io, XFS_IOLOCK_EXCL);
			mutex_unlock(&inode->i_mutex);

			iolock = XFS_IOLOCK_SHARED;
			locktype = VRWLOCK_WRITE_DIRECT;
			need_i_mutex = 0;
		}

 		xfs_rw_enter_trace(XFS_DIOWR_ENTER, io, (void *)iovp, segs,
				*offset, ioflags);
		ret = generic_file_direct_write(iocb, iovp,
				&segs, pos, offset, count, ocount);

		/*
		 * direct-io write to a hole: fall through to buffered I/O
		 * for completing the rest of the request.
		 */
		if (ret >= 0 && ret != count) {
			XFS_STATS_ADD(xs_write_bytes, ret);

			pos += ret;
			count -= ret;

			need_i_mutex = 1;
			ioflags &= ~IO_ISDIRECT;
			xfs_iunlock(xip, iolock);
			goto relock;
		}
	} else {
		xfs_rw_enter_trace(XFS_WRITE_ENTER, io, (void *)iovp, segs,
				*offset, ioflags);
		ret = generic_file_buffered_write(iocb, iovp, segs,
				pos, offset, count, ret);
	}

	current->backing_dev_info = NULL;

	if (ret == -EIOCBQUEUED && !(ioflags & IO_ISAIO))
		ret = wait_on_sync_kiocb(iocb);

	if ((ret == -ENOSPC) &&
	    DM_EVENT_ENABLED(vp->v_vfsp, xip, DM_EVENT_NOSPACE) &&
	    !(ioflags & IO_INVIS)) {

		xfs_rwunlock(bdp, locktype);
		if (need_i_mutex)
			mutex_unlock(&inode->i_mutex);
		error = XFS_SEND_NAMESP(xip->i_mount, DM_EVENT_NOSPACE, vp,
				DM_RIGHT_NULL, vp, DM_RIGHT_NULL, NULL, NULL,
				0, 0, 0); /* Delay flag intentionally  unused */
		if (error)
			goto out_nounlocks;
		if (need_i_mutex)
			mutex_lock(&inode->i_mutex);
		xfs_rwlock(bdp, locktype);
		pos = xip->i_d.di_size;
		ret = 0;
		goto retry;
	}

	isize = i_size_read(inode);
	if (unlikely(ret < 0 && ret != -EFAULT && *offset > isize))
		*offset = isize;

	if (*offset > xip->i_d.di_size) {
		xfs_ilock(xip, XFS_ILOCK_EXCL);
		if (*offset > xip->i_d.di_size) {
			xip->i_d.di_size = *offset;
			i_size_write(inode, *offset);
			xip->i_update_core = 1;
			xip->i_update_size = 1;
		}
		xfs_iunlock(xip, XFS_ILOCK_EXCL);
	}

	error = -ret;
	if (ret <= 0)
		goto out_unlock_internal;

	XFS_STATS_ADD(xs_write_bytes, ret);

	/* Handle various SYNC-type writes */
	if ((file->f_flags & O_SYNC) || IS_SYNC(inode)) {
		error = xfs_write_sync_logforce(mp, xip);
		if (error)
			goto out_unlock_internal;

		xfs_rwunlock(bdp, locktype);
		if (need_i_mutex)
			mutex_unlock(&inode->i_mutex);

		error = sync_page_range(inode, mapping, pos, ret);
		if (!error)
			error = ret;
		return error;
	}

 out_unlock_internal:
	xfs_rwunlock(bdp, locktype);
 out_unlock_mutex:
	if (need_i_mutex)
		mutex_unlock(&inode->i_mutex);
 out_nounlocks:
	return -error;
}
예제 #14
0
파일: xfs_lrw.c 프로젝트: Tigrouzen/k1099
ssize_t				/* bytes written, or (-) error */
xfs_write(
	struct xfs_inode	*xip,
	struct kiocb		*iocb,
	const struct iovec	*iovp,
	unsigned int		nsegs,
	loff_t			*offset,
	int			ioflags)
{
	struct file		*file = iocb->ki_filp;
	struct address_space	*mapping = file->f_mapping;
	struct inode		*inode = mapping->host;
	bhv_vnode_t		*vp = XFS_ITOV(xip);
	unsigned long		segs = nsegs;
	xfs_mount_t		*mp;
	ssize_t			ret = 0, error = 0;
	xfs_fsize_t		isize, new_size;
	int			iolock;
	int			eventsent = 0;
	bhv_vrwlock_t		locktype;
	size_t			ocount = 0, count;
	loff_t			pos;
	int			need_i_mutex;

	XFS_STATS_INC(xs_write_calls);

	error = generic_segment_checks(iovp, &segs, &ocount, VERIFY_READ);
	if (error)
		return error;

	count = ocount;
	pos = *offset;

	if (count == 0)
		return 0;

	mp = xip->i_mount;

	xfs_wait_for_freeze(mp, SB_FREEZE_WRITE);

	if (XFS_FORCED_SHUTDOWN(mp))
		return -EIO;

relock:
	if (ioflags & IO_ISDIRECT) {
		iolock = XFS_IOLOCK_SHARED;
		locktype = VRWLOCK_WRITE_DIRECT;
		need_i_mutex = 0;
	} else {
		iolock = XFS_IOLOCK_EXCL;
		locktype = VRWLOCK_WRITE;
		need_i_mutex = 1;
		mutex_lock(&inode->i_mutex);
	}

	xfs_ilock(xip, XFS_ILOCK_EXCL|iolock);

start:
	error = -generic_write_checks(file, &pos, &count,
					S_ISBLK(inode->i_mode));
	if (error) {
		xfs_iunlock(xip, XFS_ILOCK_EXCL|iolock);
		goto out_unlock_mutex;
	}

	if ((DM_EVENT_ENABLED(xip, DM_EVENT_WRITE) &&
	    !(ioflags & IO_INVIS) && !eventsent)) {
		int		dmflags = FILP_DELAY_FLAG(file);

		if (need_i_mutex)
			dmflags |= DM_FLAGS_IMUX;

		xfs_iunlock(xip, XFS_ILOCK_EXCL);
		error = XFS_SEND_DATA(xip->i_mount, DM_EVENT_WRITE, vp,
				      pos, count,
				      dmflags, &locktype);
		if (error) {
			goto out_unlock_internal;
		}
		xfs_ilock(xip, XFS_ILOCK_EXCL);
		eventsent = 1;

		/*
		 * The iolock was dropped and reacquired in XFS_SEND_DATA
		 * so we have to recheck the size when appending.
		 * We will only "goto start;" once, since having sent the
		 * event prevents another call to XFS_SEND_DATA, which is
		 * what allows the size to change in the first place.
		 */
		if ((file->f_flags & O_APPEND) && pos != xip->i_size)
			goto start;
	}

	if (ioflags & IO_ISDIRECT) {
		xfs_buftarg_t	*target =
			XFS_IS_REALTIME_INODE(xip) ?
				mp->m_rtdev_targp : mp->m_ddev_targp;

		if ((pos & target->bt_smask) || (count & target->bt_smask)) {
			xfs_iunlock(xip, XFS_ILOCK_EXCL|iolock);
			return XFS_ERROR(-EINVAL);
		}

		if (!need_i_mutex && (VN_CACHED(vp) || pos > xip->i_size)) {
			xfs_iunlock(xip, XFS_ILOCK_EXCL|iolock);
			iolock = XFS_IOLOCK_EXCL;
			locktype = VRWLOCK_WRITE;
			need_i_mutex = 1;
			mutex_lock(&inode->i_mutex);
			xfs_ilock(xip, XFS_ILOCK_EXCL|iolock);
			goto start;
		}
	}

	new_size = pos + count;
	if (new_size > xip->i_size)
		xip->i_new_size = new_size;

	if (likely(!(ioflags & IO_INVIS))) {
		file_update_time(file);
		xfs_ichgtime_fast(xip, inode,
				  XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
	}

	/*
	 * If the offset is beyond the size of the file, we have a couple
	 * of things to do. First, if there is already space allocated
	 * we need to either create holes or zero the disk or ...
	 *
	 * If there is a page where the previous size lands, we need
	 * to zero it out up to the new size.
	 */

	if (pos > xip->i_size) {
		error = xfs_zero_eof(xip, pos, xip->i_size);
		if (error) {
			xfs_iunlock(xip, XFS_ILOCK_EXCL);
			goto out_unlock_internal;
		}
	}
	xfs_iunlock(xip, XFS_ILOCK_EXCL);

	/*
	 * If we're writing the file then make sure to clear the
	 * setuid and setgid bits if the process is not being run
	 * by root.  This keeps people from modifying setuid and
	 * setgid binaries.
	 */

	if (((xip->i_d.di_mode & S_ISUID) ||
	    ((xip->i_d.di_mode & (S_ISGID | S_IXGRP)) ==
		(S_ISGID | S_IXGRP))) &&
	     !capable(CAP_FSETID)) {
		error = xfs_write_clear_setuid(xip);
		if (likely(!error))
			error = -remove_suid(file->f_path.dentry);
		if (unlikely(error)) {
			goto out_unlock_internal;
		}
	}

retry:
	/* We can write back this queue in page reclaim */
	current->backing_dev_info = mapping->backing_dev_info;

	if ((ioflags & IO_ISDIRECT)) {
		if (VN_CACHED(vp)) {
			WARN_ON(need_i_mutex == 0);
			xfs_inval_cached_trace(xip, pos, -1,
					(pos & PAGE_CACHE_MASK), -1);
			error = xfs_flushinval_pages(xip,
					(pos & PAGE_CACHE_MASK),
					-1, FI_REMAPF_LOCKED);
			if (error)
				goto out_unlock_internal;
		}

		if (need_i_mutex) {
			/* demote the lock now the cached pages are gone */
			xfs_ilock_demote(xip, XFS_IOLOCK_EXCL);
			mutex_unlock(&inode->i_mutex);

			iolock = XFS_IOLOCK_SHARED;
			locktype = VRWLOCK_WRITE_DIRECT;
			need_i_mutex = 0;
		}

 		xfs_rw_enter_trace(XFS_DIOWR_ENTER, xip, (void *)iovp, segs,
				*offset, ioflags);
		ret = generic_file_direct_write(iocb, iovp,
				&segs, pos, offset, count, ocount);

		/*
		 * direct-io write to a hole: fall through to buffered I/O
		 * for completing the rest of the request.
		 */
		if (ret >= 0 && ret != count) {
			XFS_STATS_ADD(xs_write_bytes, ret);

			pos += ret;
			count -= ret;

			ioflags &= ~IO_ISDIRECT;
			xfs_iunlock(xip, iolock);
			goto relock;
		}
	} else {
		xfs_rw_enter_trace(XFS_WRITE_ENTER, xip, (void *)iovp, segs,
				*offset, ioflags);
		ret = generic_file_buffered_write(iocb, iovp, segs,
				pos, offset, count, ret);
	}

	current->backing_dev_info = NULL;

	if (ret == -EIOCBQUEUED && !(ioflags & IO_ISAIO))
		ret = wait_on_sync_kiocb(iocb);

	if (ret == -ENOSPC &&
	    DM_EVENT_ENABLED(xip, DM_EVENT_NOSPACE) && !(ioflags & IO_INVIS)) {
		xfs_rwunlock(xip, locktype);
		if (need_i_mutex)
			mutex_unlock(&inode->i_mutex);
		error = XFS_SEND_NAMESP(xip->i_mount, DM_EVENT_NOSPACE, vp,
				DM_RIGHT_NULL, vp, DM_RIGHT_NULL, NULL, NULL,
				0, 0, 0); /* Delay flag intentionally  unused */
		if (need_i_mutex)
			mutex_lock(&inode->i_mutex);
		xfs_rwlock(xip, locktype);
		if (error)
			goto out_unlock_internal;
		pos = xip->i_size;
		ret = 0;
		goto retry;
	}

	isize = i_size_read(inode);
	if (unlikely(ret < 0 && ret != -EFAULT && *offset > isize))
		*offset = isize;

	if (*offset > xip->i_size) {
		xfs_ilock(xip, XFS_ILOCK_EXCL);
		if (*offset > xip->i_size)
			xip->i_size = *offset;
		xfs_iunlock(xip, XFS_ILOCK_EXCL);
	}

	error = -ret;
	if (ret <= 0)
		goto out_unlock_internal;

	XFS_STATS_ADD(xs_write_bytes, ret);

	/* Handle various SYNC-type writes */
	if ((file->f_flags & O_SYNC) || IS_SYNC(inode)) {
		int error2;
		xfs_rwunlock(xip, locktype);
		if (need_i_mutex)
			mutex_unlock(&inode->i_mutex);
		error2 = sync_page_range(inode, mapping, pos, ret);
		if (!error)
			error = error2;
		if (need_i_mutex)
			mutex_lock(&inode->i_mutex);
		xfs_rwlock(xip, locktype);
		error2 = xfs_write_sync_logforce(mp, xip);
		if (!error)
			error = error2;
	}

 out_unlock_internal:
	if (xip->i_new_size) {
		xfs_ilock(xip, XFS_ILOCK_EXCL);
		xip->i_new_size = 0;
		/*
		 * If this was a direct or synchronous I/O that failed (such
		 * as ENOSPC) then part of the I/O may have been written to
		 * disk before the error occured.  In this case the on-disk
		 * file size may have been adjusted beyond the in-memory file
		 * size and now needs to be truncated back.
		 */
		if (xip->i_d.di_size > xip->i_size)
			xip->i_d.di_size = xip->i_size;
		xfs_iunlock(xip, XFS_ILOCK_EXCL);
	}
	xfs_rwunlock(xip, locktype);
 out_unlock_mutex:
	if (need_i_mutex)
		mutex_unlock(&inode->i_mutex);
	return -error;
}
예제 #15
0
파일: xfs_lrw.c 프로젝트: Tigrouzen/k1099
ssize_t			/* bytes read, or (-)  error */
xfs_read(
	xfs_inode_t		*ip,
	struct kiocb		*iocb,
	const struct iovec	*iovp,
	unsigned int		segs,
	loff_t			*offset,
	int			ioflags)
{
	struct file		*file = iocb->ki_filp;
	struct inode		*inode = file->f_mapping->host;
	bhv_vnode_t		*vp = XFS_ITOV(ip);
	xfs_mount_t		*mp = ip->i_mount;
	size_t			size = 0;
	ssize_t			ret = 0;
	xfs_fsize_t		n;
	unsigned long		seg;


	XFS_STATS_INC(xs_read_calls);

	/* START copy & waste from filemap.c */
	for (seg = 0; seg < segs; seg++) {
		const struct iovec *iv = &iovp[seg];

		/*
		 * If any segment has a negative length, or the cumulative
		 * length ever wraps negative then return -EINVAL.
		 */
		size += iv->iov_len;
		if (unlikely((ssize_t)(size|iv->iov_len) < 0))
			return XFS_ERROR(-EINVAL);
	}
	/* END copy & waste from filemap.c */

	if (unlikely(ioflags & IO_ISDIRECT)) {
		xfs_buftarg_t	*target =
			XFS_IS_REALTIME_INODE(ip) ?
				mp->m_rtdev_targp : mp->m_ddev_targp;
		if ((*offset & target->bt_smask) ||
		    (size & target->bt_smask)) {
			if (*offset == ip->i_size) {
				return (0);
			}
			return -XFS_ERROR(EINVAL);
		}
	}

	n = XFS_MAXIOFFSET(mp) - *offset;
	if ((n <= 0) || (size == 0))
		return 0;

	if (n < size)
		size = n;

	if (XFS_FORCED_SHUTDOWN(mp))
		return -EIO;

	if (unlikely(ioflags & IO_ISDIRECT))
		mutex_lock(&inode->i_mutex);
	xfs_ilock(ip, XFS_IOLOCK_SHARED);

	if (DM_EVENT_ENABLED(ip, DM_EVENT_READ) && !(ioflags & IO_INVIS)) {
		bhv_vrwlock_t locktype = VRWLOCK_READ;
		int dmflags = FILP_DELAY_FLAG(file) | DM_SEM_FLAG_RD(ioflags);

		ret = -XFS_SEND_DATA(mp, DM_EVENT_READ, vp, *offset, size,
					dmflags, &locktype);
		if (ret) {
			xfs_iunlock(ip, XFS_IOLOCK_SHARED);
			if (unlikely(ioflags & IO_ISDIRECT))
				mutex_unlock(&inode->i_mutex);
			return ret;
		}
	}

	if (unlikely(ioflags & IO_ISDIRECT)) {
		if (VN_CACHED(vp))
			ret = xfs_flushinval_pages(ip, (*offset & PAGE_CACHE_MASK),
						    -1, FI_REMAPF_LOCKED);
		mutex_unlock(&inode->i_mutex);
		if (ret) {
			xfs_iunlock(ip, XFS_IOLOCK_SHARED);
			return ret;
		}
	}

	xfs_rw_enter_trace(XFS_READ_ENTER, ip,
				(void *)iovp, segs, *offset, ioflags);

	iocb->ki_pos = *offset;
	ret = generic_file_aio_read(iocb, iovp, segs, *offset);
	if (ret == -EIOCBQUEUED && !(ioflags & IO_ISAIO))
		ret = wait_on_sync_kiocb(iocb);
	if (ret > 0)
		XFS_STATS_ADD(xs_read_bytes, ret);

	xfs_iunlock(ip, XFS_IOLOCK_SHARED);
	return ret;
}