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Remove unused header files for MAC and CAP checking functionality.

xfs_mac.h and xfs_cap.h provide definitions and macros that aren't
used anywhere in XFS at all. They are left-overs from "to be implement
at some point in the future" functionality that Irix XFS has. If this
functionality ever goes into Linux, it will be provided at a different
layer, most likely through the security hooks in the kernel so we will
never need this functionality in XFS.

Patch provided by Eric Sandeen (sandeen@sandeen.net).
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Merge of xfs-linux-melb:xfs-kern:28036a by kenmcd.

  Remove unused xfs_cap.h/xfs_mac.h header files.
  Signed-off-by: Eric Sandeen <sandeen@sandeen.net>

/*
 * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
 * All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it would 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 the Free Software Foundation,
 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_bit.h"
#include "xfs_log.h"
#include "xfs_inum.h"
#include "xfs_trans.h"
#include "xfs_sb.h"
#include "xfs_ag.h"
#include "xfs_dir2.h"
#include "xfs_alloc.h"
#include "xfs_dmapi.h"
#include "xfs_quota.h"
#include "xfs_mount.h"
#include "xfs_bmap_btree.h"
#include "xfs_alloc_btree.h"
#include "xfs_ialloc_btree.h"
#include "xfs_dir2_sf.h"
#include "xfs_attr_sf.h"
#include "xfs_dinode.h"
#include "xfs_inode.h"
#include "xfs_bmap.h"
#include "xfs_btree.h"
#include "xfs_ialloc.h"
#include "xfs_rtalloc.h"
#include "xfs_error.h"
#include "xfs_itable.h"
#include "xfs_rw.h"
#include "xfs_refcache.h"
#include "xfs_acl.h"
#include "xfs_attr.h"
#include "xfs_inode_item.h"
#include "xfs_buf_item.h"
#include "xfs_utils.h"
#include "xfs_iomap.h"

#include <linux/capability.h>

#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,4,22)
#define	do_down_read(x)	down_read(x)
#define do_up_read(x)	up_read(x)
#else
#define	do_down_read(x)
#define do_up_read(x)
#endif

static inline void dm_sem_up(
	struct inode *inode,
	int ioflags)
{
	if (ioflags & IO_ISDIRECT) {
		do_up_read(&inode->i_alloc_sem);
	}
	else {
		up(&inode->i_sem);
	}
}

static inline void dm_sem_down(
	struct inode *inode,
	int ioflags)
{
	if (ioflags & IO_ISDIRECT) {
		do_down_read(&inode->i_alloc_sem);
	}
	else {
		down(&inode->i_sem);
	}
}


#if defined(XFS_RW_TRACE)
void
xfs_rw_enter_trace(
	int		tag,
	xfs_iocore_t	*io,
	const char	*buf,
	size_t		size,
	loff_t		offset,
	int		ioflags)
{
	xfs_inode_t	*ip = XFS_IO_INODE(io);

	if (ip->i_rwtrace == NULL)
		return;
	ktrace_enter(ip->i_rwtrace,
		(void *)(unsigned long)tag,
		(void *)ip,
		(void *)((unsigned long)((ip->i_d.di_size >> 32) & 0xffffffff)),
		(void *)((unsigned long)(ip->i_d.di_size & 0xffffffff)),
		(void *)(__psint_t)buf,
		(void *)((unsigned long)size),
		(void *)((unsigned long)((offset >> 32) & 0xffffffff)),
		(void *)((unsigned long)(offset & 0xffffffff)),
		(void *)((unsigned long)ioflags),
		(void *)((unsigned long)((io->io_new_size >> 32) & 0xffffffff)),
		(void *)((unsigned long)(io->io_new_size & 0xffffffff)),
		(void *)((unsigned long)current_pid()),
		(void *)NULL,
		(void *)NULL,
		(void *)NULL,
		(void *)NULL);
}

void
xfs_inval_cached_trace(
	xfs_iocore_t	*io,
	xfs_off_t	offset,
	xfs_off_t	len,
	xfs_off_t	first,
	xfs_off_t	last)
{
	xfs_inode_t	*ip = XFS_IO_INODE(io);

	if (ip->i_rwtrace == NULL)
		return;
	ktrace_enter(ip->i_rwtrace,
		(void *)(__psint_t)XFS_INVAL_CACHED,
		(void *)ip,
		(void *)((unsigned long)((offset >> 32) & 0xffffffff)),
		(void *)((unsigned long)(offset & 0xffffffff)),
		(void *)((unsigned long)((len >> 32) & 0xffffffff)),
		(void *)((unsigned long)(len & 0xffffffff)),
		(void *)((unsigned long)((first >> 32) & 0xffffffff)),
		(void *)((unsigned long)(first & 0xffffffff)),
		(void *)((unsigned long)((last >> 32) & 0xffffffff)),
		(void *)((unsigned long)(last & 0xffffffff)),
		(void *)((unsigned long)current_pid()),
		(void *)NULL,
		(void *)NULL,
		(void *)NULL,
		(void *)NULL,
		(void *)NULL);
}
#endif

/*
 *	xfs_iozero
 *
 *	xfs_iozero clears the specified range of buffer supplied,
 *	and marks all the affected blocks as valid and modified.  If
 *	an affected block is not allocated, it will be allocated.  If
 *	an affected block is not completely overwritten, and is not
 *	valid before the operation, it will be read from disk before
 *	being partially zeroed.
 */
STATIC int
xfs_iozero(
	struct inode		*ip,	/* inode			*/
	loff_t			pos,	/* offset in file		*/
	size_t			count,	/* size of data to zero		*/
	loff_t			end_size)	/* max file size to set */
{
	unsigned		bytes;
	struct page		*page;
	struct address_space	*mapping;
	char			*kaddr;
	int			status;

	mapping = ip->i_mapping;
	do {
		unsigned long index, offset;

		offset = (pos & (PAGE_CACHE_SIZE -1)); /* Within page */
		index = pos >> PAGE_CACHE_SHIFT;
		bytes = PAGE_CACHE_SIZE - offset;
		if (bytes > count)
			bytes = count;

		status = -ENOMEM;
		page = grab_cache_page(mapping, index);
		if (!page)
			break;

		kaddr = kmap(page);
		status = mapping->a_ops->prepare_write(NULL, page, offset,
							offset + bytes);
		if (status) {
			goto unlock;
		}

		memset((void *) (kaddr + offset), 0, bytes);
		flush_dcache_page(page);
		status = mapping->a_ops->commit_write(NULL, page, offset,
							offset + bytes);
		if (!status) {
			pos += bytes;
			count -= bytes;
			if (pos > i_size_read(ip))
				i_size_write(ip, pos < end_size ? pos : end_size);
		}

unlock:
		kunmap(page);
		unlock_page(page);
		page_cache_release(page);
		if (status)
			break;
	} while (count);

	return (-status);
}

/*
 * 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.
 */
STATIC void
xfs_inval_cached_pages(
	bhv_vnode_t	*vp,
	xfs_iocore_t	*io,
	xfs_off_t	offset)
{
	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.
	 */
	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 (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);
	bhv_vop_flushinval_pages(vp, ctooff(offtoct(offset)), -1, FI_REMAPF_LOCKED);
	XFS_ILOCK_DEMOTE(mp, io, XFS_IOLOCK_EXCL);
}

ssize_t			/* bytes read, or (-)  error */
xfs_read(
	bhv_desc_t      *bdp,
	struct file	*file,
	char		*buf,
	size_t		size,
	loff_t		*offset,
	int		ioflags,
	cred_t          *credp)
{
	ssize_t		ret;
	xfs_fsize_t	n;
	xfs_inode_t	*ip;
	xfs_mount_t	*mp;

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

	XFS_STATS_INC(xs_read_calls);

	if (unlikely(ioflags & IO_ISDIRECT)) {
		if ((ssize_t)size < 0)
			return -XFS_ERROR(EINVAL);
		if (((__psint_t)buf & BBMASK) ||
		    (*offset & mp->m_blockmask) ||
		    (size & mp->m_blockmask)) {
			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 (!(ioflags & IO_ISLOCKED))
		xfs_ilock(ip, XFS_IOLOCK_SHARED);

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

		error = XFS_SEND_DATA(mp, DM_EVENT_READ, BHV_TO_VNODE(bdp), *offset, size,
				      dmflags, &locktype);
		if (error) {
			if (!(ioflags & IO_ISLOCKED))
				xfs_iunlock(ip, XFS_IOLOCK_SHARED);
			return -error;
		}
	}

	if (unlikely(ioflags & IO_ISDIRECT)) {
		xfs_rw_enter_trace(XFS_DIORD_ENTER, &ip->i_iocore,
					buf, size, *offset, ioflags);
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,4,22)
		ret = (*offset < ip->i_d.di_size) ?
			do_generic_direct_read(file, buf, size, offset) : 0;
		UPDATE_ATIME(file->f_dentry->d_inode);
#else
		ret = generic_file_read(file, buf, size, offset);
#endif
	} else {
		xfs_rw_enter_trace(XFS_READ_ENTER, &ip->i_iocore,
					buf, size, *offset, ioflags);
		ret = generic_file_read(file, buf, size, offset);
	}

	if (ret > 0)
		XFS_STATS_ADD(xs_read_bytes, ret);

	if (!(ioflags & IO_ISLOCKED))
		xfs_iunlock(ip, XFS_IOLOCK_SHARED);

	if (unlikely(ioflags & IO_INVIS)) {
		/* generic_file_read updates the atime but we need to
		 * undo that because this I/O was supposed to be invisible.
		 */
		struct inode *inode = vn_to_inode(BHV_TO_VNODE(bdp));
		inode->i_atime = ip->i_d.di_atime.t_sec;
	} else {
		xfs_ichgtime(ip, XFS_ICHGTIME_ACC);
	}

	return ret;
}

/*
 * This routine is called to handle zeroing any space in the last
 * block of the file that is beyond the EOF.  We do this since the
 * size is being increased without writing anything to that block
 * and we don't want anyone to read the garbage on the disk.
 */
STATIC int				/* error (positive) */
xfs_zero_last_block(
	struct inode	*ip,
	xfs_iocore_t	*io,
	xfs_fsize_t	isize,
	xfs_fsize_t	end_size)
{
	xfs_fileoff_t	last_fsb;
	xfs_mount_t	*mp;
	int		nimaps;
	int		zero_offset;
	int		zero_len;
	int		error = 0;
	xfs_bmbt_irec_t	imap;
	loff_t		loff;

	ASSERT(ismrlocked(io->io_lock, MR_UPDATE) != 0);

	mp = io->io_mount;

	zero_offset = XFS_B_FSB_OFFSET(mp, isize);
	if (zero_offset == 0) {
		/*
		 * There are no extra bytes in the last block on disk to
		 * zero, so return.
		 */
		return 0;
	}

	last_fsb = XFS_B_TO_FSBT(mp, isize);
	nimaps = 1;
	error = XFS_BMAPI(mp, NULL, io, last_fsb, 1, 0, NULL, 0, &imap,
			  &nimaps, NULL, NULL);
	if (error) {
		return error;
	}
	ASSERT(nimaps > 0);
	/*
	 * If the block underlying isize is just a hole, then there
	 * is nothing to zero.
	 */
	if (imap.br_startblock == HOLESTARTBLOCK) {
		return 0;
	}
	/*
	 * Zero the part of the last block beyond the EOF, and write it
	 * out sync.  We need to drop the ilock while we do this so we
	 * don't deadlock when the buffer cache calls back to us.
	 */
	XFS_IUNLOCK(mp, io, XFS_ILOCK_EXCL| XFS_EXTSIZE_RD);
	loff = XFS_FSB_TO_B(mp, last_fsb);

	zero_len = mp->m_sb.sb_blocksize - zero_offset;

	error = xfs_iozero(ip, loff + zero_offset, zero_len, end_size);

	XFS_ILOCK(mp, io, XFS_ILOCK_EXCL|XFS_EXTSIZE_RD);
	ASSERT(error >= 0);
	return error;
}

/*
 * Zero any on disk space between the current EOF and the new,
 * larger EOF.  This handles the normal case of zeroing the remainder
 * of the last block in the file and the unusual case of zeroing blocks
 * out beyond the size of the file.  This second case only happens
 * with fixed size extents and when the system crashes before the inode
 * size was updated but after blocks were allocated.  If fill is set,
 * then any holes in the range are filled and zeroed.  If not, the holes
 * are left alone as holes.
 */

int					/* error (positive) */
xfs_zero_eof(
	bhv_vnode_t	*vp,
	xfs_iocore_t	*io,
	xfs_off_t	offset,		/* starting I/O offset */
	xfs_fsize_t	isize,		/* current inode size */
	xfs_fsize_t	end_size)	/* terminal inode size */
{
	struct inode	*ip = vn_to_inode(vp);
	xfs_fileoff_t	start_zero_fsb;
	xfs_fileoff_t	end_zero_fsb;
	xfs_fileoff_t	zero_count_fsb;
	xfs_fileoff_t	last_fsb;
	xfs_mount_t	*mp;
	int		nimaps;
	int		error = 0;
	xfs_bmbt_irec_t	imap;

	ASSERT(ismrlocked(io->io_lock, MR_UPDATE));
	ASSERT(ismrlocked(io->io_iolock, MR_UPDATE));
	ASSERT(offset > isize);

	mp = io->io_mount;

	/*
	 * First handle zeroing the block on which isize resides.
	 * We only zero a part of that block so it is handled specially.
	 */
	error = xfs_zero_last_block(ip, io, isize, end_size);
	if (error) {
		ASSERT(ismrlocked(io->io_lock, MR_UPDATE));
		ASSERT(ismrlocked(io->io_iolock, MR_UPDATE));
		return error;
	}

	/*
	 * Calculate the range between the new size and the old
	 * where blocks needing to be zeroed may exist.  To get the
	 * block where the last byte in the file currently resides,
	 * we need to subtract one from the size and truncate back
	 * to a block boundary.  We subtract 1 in case the size is
	 * exactly on a block boundary.
	 */
	last_fsb = isize ? XFS_B_TO_FSBT(mp, isize - 1) : (xfs_fileoff_t)-1;
	start_zero_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)isize);
	end_zero_fsb = XFS_B_TO_FSBT(mp, offset - 1);
	ASSERT((xfs_sfiloff_t)last_fsb < (xfs_sfiloff_t)start_zero_fsb);
	if (last_fsb == end_zero_fsb) {
		/*
		 * The size was only incremented on its last block.
		 * We took care of that above, so just return.
		 */
		return 0;
	}

	ASSERT(start_zero_fsb <= end_zero_fsb);
	while (start_zero_fsb <= end_zero_fsb) {
		nimaps = 1;
		zero_count_fsb = end_zero_fsb - start_zero_fsb + 1;
		error = XFS_BMAPI(mp, NULL, io, start_zero_fsb, zero_count_fsb,
				  0, NULL, 0, &imap, &nimaps, NULL, NULL);
		if (error) {
			ASSERT(ismrlocked(io->io_lock, MR_UPDATE));
			ASSERT(ismrlocked(io->io_iolock, MR_UPDATE));
			return error;
		}
		ASSERT(nimaps > 0);

		if (imap.br_state == XFS_EXT_UNWRITTEN ||
		    imap.br_startblock == HOLESTARTBLOCK) {
			/*
			 * This loop handles initializing pages that were
			 * partially initialized by the code below this
			 * loop. It basically zeroes the part of the page
			 * that sits on a hole and sets the page as P_HOLE
			 * and calls remapf if it is a mapped file.
			 */
			start_zero_fsb = imap.br_startoff + imap.br_blockcount;
			ASSERT(start_zero_fsb <= (end_zero_fsb + 1));
			continue;
		}

		/*
		 * There are blocks we need to zero.
		 * Drop the inode lock while we're doing the I/O.
		 * We'll still have the iolock to protect us.
		 */
		XFS_IUNLOCK(mp, io, XFS_ILOCK_EXCL|XFS_EXTSIZE_RD);

		error = xfs_iozero(ip,
				   XFS_FSB_TO_B(mp, start_zero_fsb),
				   XFS_FSB_TO_B(mp, imap.br_blockcount),
				   end_size);
		if (error) {
			goto out_lock;
		}

		start_zero_fsb = imap.br_startoff + imap.br_blockcount;
		ASSERT(start_zero_fsb <= (end_zero_fsb + 1));

		XFS_ILOCK(mp, io, XFS_ILOCK_EXCL|XFS_EXTSIZE_RD);
	}

	return 0;

out_lock:

	XFS_ILOCK(mp, io, XFS_ILOCK_EXCL|XFS_EXTSIZE_RD);
	ASSERT(error >= 0);
	return error;
}

ssize_t				/* bytes written, or (-) error */
xfs_write(
	bhv_desc_t      *bdp,
	struct file	*file,
	const char	*buf,
	size_t		size,
	loff_t		*offset,
	int		ioflags,
	cred_t          *credp)
{
	xfs_inode_t	*xip;
	xfs_mount_t	*mp;
	ssize_t		ret;
	int		error = 0;
	xfs_fsize_t     isize, new_size;
	xfs_fsize_t	n, limit;
	struct inode	*inode;
	xfs_iocore_t    *io;
	bhv_vnode_t	*vp;
	int		iolock;
	int		eventsent = 0;
	bhv_vrwlock_t	locktype;

	XFS_STATS_INC(xs_write_calls);

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

	if (size == 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(xip->i_mount))
		return -EIO;

	if (unlikely(ioflags & IO_ISDIRECT)) {
		if (((__psint_t)buf & BBMASK) ||
		    (*offset & mp->m_blockmask) ||
		    (size  & mp->m_blockmask)) {
			return XFS_ERROR(-EINVAL);
		}
		iolock = XFS_IOLOCK_SHARED;
		locktype = VRWLOCK_WRITE_DIRECT;
	} else {
		iolock = XFS_IOLOCK_EXCL;
		locktype = VRWLOCK_WRITE;
	}

	if (ioflags & IO_ISLOCKED)
		iolock = 0;

	xfs_ilock(xip, XFS_ILOCK_EXCL|iolock);

	isize = xip->i_d.di_size;
	limit = XFS_MAXIOFFSET(mp);

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

start:
	n = limit - *offset;
	if (n <= 0) {
		xfs_iunlock(xip, XFS_ILOCK_EXCL|iolock);
		return -EFBIG;
	}
	if (n < size)
		size = n;

	new_size = *offset + size;
	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 = *offset;
		int dmflags = FILP_DELAY_FLAG(file) | DM_SEM_FLAG_RD(ioflags);

		xfs_iunlock(xip, XFS_ILOCK_EXCL);
		error = XFS_SEND_DATA(xip->i_mount, DM_EVENT_WRITE, vp,
				      *offset, size,
				      dmflags, &locktype);
		if (error) {
			if (iolock)
				xfs_iunlock(xip, iolock);
			return -error;
		}
		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 != xip->i_d.di_size) {
			*offset = isize = xip->i_d.di_size;
			goto start;
		}
	}

	/*
	 * 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 (!(ioflags & IO_ISDIRECT) && (*offset > isize && isize)) {
		error = xfs_zero_eof(BHV_TO_VNODE(bdp), io, *offset,
			isize, *offset + size);
		if (error) {
			xfs_iunlock(xip, XFS_ILOCK_EXCL|iolock);
			return(-error);
		}
	}
	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 (error) {
			xfs_iunlock(xip, iolock);
			return -error;
		}
	}


#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,4,22)
	if ((ssize_t) size < 0) {
		ret = -EINVAL;
		goto error;
	}

	if (!access_ok(VERIFY_READ, buf, size)) {
		ret = -EINVAL;
		goto error;
	}
#else
#define do_generic_direct_write(file, buf, size, offset)	\
	generic_file_write_nolock(file, buf, size, offset)
#define do_generic_file_write(file, buf, size, offset)		\
	generic_file_write_nolock(file, buf, size, offset)
#endif

retry:
	if (unlikely(ioflags & IO_ISDIRECT)) {
		xfs_inval_cached_pages(vp, io, *offset);
		xfs_rw_enter_trace(XFS_DIOWR_ENTER,
					io, buf, size, *offset, ioflags);
		ret = do_generic_direct_write(file, buf, size, offset);
	} else {
		xfs_rw_enter_trace(XFS_WRITE_ENTER,
					io, buf, size, *offset, ioflags);
		ret = do_generic_file_write(file, buf, size, offset);
	}

	if (unlikely(ioflags & IO_INVIS)) {
		/* generic_file_write updates the mtime/ctime but we need
		 * to undo that because this I/O was supposed to be
		 * invisible.
		 */
		inode->i_mtime = xip->i_d.di_mtime.t_sec;
		inode->i_ctime = xip->i_d.di_ctime.t_sec;
	} else {
		xfs_ichgtime(xip, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
	}

	if ((ret == -ENOSPC) &&
	    DM_EVENT_ENABLED(vp->v_vfsp, xip, DM_EVENT_NOSPACE) &&
	    !(ioflags & IO_INVIS)) {
		dm_sem_up(inode, ioflags);
		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 */
		dm_sem_down(inode, ioflags);
		if (error)
			return -error;
		xfs_rwlock(bdp, locktype);
		*offset = xip->i_d.di_size;
		goto retry;
	}

#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,4,22)
error:
#endif
	if (ret <= 0) {
		if (iolock)
			xfs_rwunlock(bdp, locktype);
		return ret;
	}

	XFS_STATS_ADD(xs_write_bytes, ret);

        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;
			mark_inode_dirty_sync(inode);
		}
		xfs_iunlock(xip, XFS_ILOCK_EXCL);
	}

	/* Handle various SYNC-type writes */
	if ((file->f_flags & O_SYNC) || IS_SYNC(file->f_dentry->d_inode)) {
		error = xfs_write_sync_logforce(mp, xip);
		if (error)
			ret = -error;
	}

	/*
	 * If we are coming from an nfsd thread then insert into the
	 * reference cache.
	 */

	if (!strcmp(current->comm, "nfsd"))
		xfs_refcache_insert(xip);

	/* Drop lock this way - the old refcache release is in here */
	if (iolock)
		xfs_rwunlock(bdp, locktype);

	return ret;
}

/*
 * All xfs metadata buffers except log state machine buffers
 * get this attached as their b_bdstrat callback function.
 * This is so that we can catch a buffer
 * after prematurely unpinning it to forcibly shutdown the filesystem.
 */
int
xfs_bdstrat_cb(struct xfs_buf *bp)
{
	xfs_mount_t	*mp;

	mp = XFS_BUF_FSPRIVATE3(bp, xfs_mount_t *);
	if (!XFS_FORCED_SHUTDOWN(mp)) {
		xfs_buf_iorequest(bp);
		return 0;
	} else {
		xfs_buftrace("XFS__BDSTRAT IOERROR", bp);
		/*
		 * Metadata write that didn't get logged but
		 * written delayed anyway. These aren't associated
		 * with a transaction, and can be ignored.
		 */
		if (XFS_BUF_IODONE_FUNC(bp) == NULL &&
		    (XFS_BUF_ISREAD(bp)) == 0)
			return (xfs_bioerror_relse(bp));
		else
			return (xfs_bioerror(bp));
	}
}


int
xfs_bmap(bhv_desc_t	*bdp,
	xfs_off_t	offset,
	ssize_t		count,
	int		flags,
	xfs_iomap_t	*iomapp,
	int		*niomaps)
{
	xfs_inode_t	*ip = XFS_BHVTOI(bdp);
	xfs_iocore_t	*io = &ip->i_iocore;

	ASSERT((ip->i_d.di_mode & S_IFMT) == S_IFREG);
	ASSERT(((ip->i_d.di_flags & XFS_DIFLAG_REALTIME) != 0) ==
	       ((ip->i_iocore.io_flags & XFS_IOCORE_RT) != 0));

	return xfs_iomap(io, offset, count, flags, iomapp, niomaps);
}

/*
 * Wrapper around bdstrat so that we can stop data
 * from going to disk in case we are shutting down the filesystem.
 * Typically user data goes thru this path; one of the exceptions
 * is the superblock.
 */
int
xfsbdstrat(
	struct xfs_mount	*mp,
	struct xfs_buf		*bp)
{
	ASSERT(mp);
	if (!XFS_FORCED_SHUTDOWN(mp)) {
		xfs_buf_iorequest(bp);
		return 0;
	}

	xfs_buftrace("XFSBDSTRAT IOERROR", bp);
	return (xfs_bioerror_relse(bp));
}

/*
 * If the underlying (data/log/rt) device is readonly, there are some
 * operations that cannot proceed.
 */
int
xfs_dev_is_read_only(
	xfs_mount_t		*mp,
	char			*message)
{
	if (xfs_readonly_buftarg(mp->m_ddev_targp) ||
	    xfs_readonly_buftarg(mp->m_logdev_targp) ||
	    (mp->m_rtdev_targp && xfs_readonly_buftarg(mp->m_rtdev_targp))) {
		cmn_err(CE_NOTE,
			"XFS: %s required on read-only device.", message);
		cmn_err(CE_NOTE,
			"XFS: write access unavailable, cannot proceed.");
		return EROFS;
	}
	return 0;
}