xfs: merge xfs_lrw.c into xfs_file.c

Currently the code to implement the file operations is split over
two small files.  Merge the content of xfs_lrw.c into xfs_file.c to
have it in one place.  Note that I haven't done various cleanups
that are possible after this yet, they will follow in the next
patch.  Also the function xfs_dev_is_read_only which was in
xfs_lrw.c before really doesn't fit in here at all and was moved to
xfs_mount.c.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>

1 files changed, 723 insertions, 0 deletions

diff --git a/fs/xfs/linux-2.6/xfs_file.c b/fs/xfs/linux-2.6/xfs_file.c
index 3805ada98747..51fc510828a4 100644
--- a/fs/xfs/linux-2.6/xfs_file.c
+++ b/fs/xfs/linux-2.6/xfs_file.c
@@ -16,6 +16,7 @@
  * 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"
@@ -34,16 +35,738 @@
 #include "xfs_dir2_sf.h"
 #include "xfs_dinode.h"
 #include "xfs_inode.h"
+#include "xfs_bmap.h"
 #include "xfs_error.h"
 #include "xfs_rw.h"
 #include "xfs_vnodeops.h"
 #include "xfs_da_btree.h"
 #include "xfs_ioctl.h"
+#include "xfs_trace.h"
 
 #include <linux/dcache.h>
 
 static const struct vm_operations_struct xfs_file_vm_ops;
 
+/*
+ *      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 xfs_inode        *ip,    /* inode                        */
+        loff_t                  pos,    /* offset in file               */
+        size_t                  count)  /* size of data to zero         */
+{
+        struct page             *page;
+        struct address_space    *mapping;
+        int                     status;
+
+        mapping = VFS_I(ip)->i_mapping;
+        do {
+                unsigned offset, bytes;
+                void *fsdata;
+
+                offset = (pos & (PAGE_CACHE_SIZE -1)); /* Within page */
+                bytes = PAGE_CACHE_SIZE - offset;
+                if (bytes > count)
+                        bytes = count;
+
+                status = pagecache_write_begin(NULL, mapping, pos, bytes,
+                                        AOP_FLAG_UNINTERRUPTIBLE,
+                                        &page, &fsdata);
+                if (status)
+                        break;
+
+                zero_user(page, offset, bytes);
+
+                status = pagecache_write_end(NULL, mapping, pos, bytes, bytes,
+                                        page, fsdata);
+                WARN_ON(status <= 0); /* can't return less than zero! */
+                pos += bytes;
+                count -= bytes;
+                status = 0;
+        } while (count);
+
+        return (-status);
+}
+
+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;
+        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)) {
+                int dmflags = FILP_DELAY_FLAG(file) | DM_SEM_FLAG_RD(ioflags);
+                int iolock = XFS_IOLOCK_SHARED;
+
+                ret = -XFS_SEND_DATA(mp, DM_EVENT_READ, ip, *offset, size,
+                                        dmflags, &iolock);
+                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 (inode->i_mapping->nrpages)
+                        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;
+                }
+        }
+
+        trace_xfs_file_read(ip, size, *offset, ioflags);
+
+        iocb->ki_pos = *offset;
+        ret = generic_file_aio_read(iocb, iovp, segs, *offset);
+        if (ret > 0)
+                XFS_STATS_ADD(xs_read_bytes, ret);
+
+        xfs_iunlock(ip, XFS_IOLOCK_SHARED);
+        return ret;
+}
+
+ssize_t
+xfs_splice_read(
+        xfs_inode_t             *ip,
+        struct file             *infilp,
+        loff_t                  *ppos,
+        struct pipe_inode_info  *pipe,
+        size_t                  count,
+        int                     flags,
+        int                     ioflags)
+{
+        xfs_mount_t             *mp = ip->i_mount;
+        ssize_t                 ret;
+
+        XFS_STATS_INC(xs_read_calls);
+        if (XFS_FORCED_SHUTDOWN(ip->i_mount))
+                return -EIO;
+
+        xfs_ilock(ip, XFS_IOLOCK_SHARED);
+
+        if (DM_EVENT_ENABLED(ip, DM_EVENT_READ) && !(ioflags & IO_INVIS)) {
+                int iolock = XFS_IOLOCK_SHARED;
+                int error;
+
+                error = XFS_SEND_DATA(mp, DM_EVENT_READ, ip, *ppos, count,
+                                        FILP_DELAY_FLAG(infilp), &iolock);
+                if (error) {
+                        xfs_iunlock(ip, XFS_IOLOCK_SHARED);
+                        return -error;
+                }
+        }
+
+        trace_xfs_file_splice_read(ip, count, *ppos, ioflags);
+
+        ret = generic_file_splice_read(infilp, ppos, pipe, count, flags);
+        if (ret > 0)
+                XFS_STATS_ADD(xs_read_bytes, ret);
+
+        xfs_iunlock(ip, XFS_IOLOCK_SHARED);
+        return ret;
+}
+
+ssize_t
+xfs_splice_write(
+        xfs_inode_t             *ip,
+        struct pipe_inode_info  *pipe,
+        struct file             *outfilp,
+        loff_t                  *ppos,
+        size_t                  count,
+        int                     flags,
+        int                     ioflags)
+{
+        xfs_mount_t             *mp = ip->i_mount;
+        ssize_t                 ret;
+        struct inode            *inode = outfilp->f_mapping->host;
+        xfs_fsize_t             isize, new_size;
+
+        XFS_STATS_INC(xs_write_calls);
+        if (XFS_FORCED_SHUTDOWN(ip->i_mount))
+                return -EIO;
+
+        xfs_ilock(ip, XFS_IOLOCK_EXCL);
+
+        if (DM_EVENT_ENABLED(ip, DM_EVENT_WRITE) && !(ioflags & IO_INVIS)) {
+                int iolock = XFS_IOLOCK_EXCL;
+                int error;
+
+                error = XFS_SEND_DATA(mp, DM_EVENT_WRITE, ip, *ppos, count,
+                                        FILP_DELAY_FLAG(outfilp), &iolock);
+                if (error) {
+                        xfs_iunlock(ip, XFS_IOLOCK_EXCL);
+                        return -error;
+                }
+        }
+
+        new_size = *ppos + count;
+
+        xfs_ilock(ip, XFS_ILOCK_EXCL);
+        if (new_size > ip->i_size)
+                ip->i_new_size = new_size;
+        xfs_iunlock(ip, XFS_ILOCK_EXCL);
+
+        trace_xfs_file_splice_write(ip, count, *ppos, ioflags);
+
+        ret = generic_file_splice_write(pipe, outfilp, ppos, count, flags);
+        if (ret > 0)
+                XFS_STATS_ADD(xs_write_bytes, ret);
+
+        isize = i_size_read(inode);
+        if (unlikely(ret < 0 && ret != -EFAULT && *ppos > isize))
+                *ppos = isize;
+
+        if (*ppos > ip->i_size) {
+                xfs_ilock(ip, XFS_ILOCK_EXCL);
+                if (*ppos > ip->i_size)
+                        ip->i_size = *ppos;
+                xfs_iunlock(ip, XFS_ILOCK_EXCL);
+        }
+
+        if (ip->i_new_size) {
+                xfs_ilock(ip, XFS_ILOCK_EXCL);
+                ip->i_new_size = 0;
+                if (ip->i_d.di_size > ip->i_size)
+                        ip->i_d.di_size = ip->i_size;
+                xfs_iunlock(ip, XFS_ILOCK_EXCL);
+        }
+        xfs_iunlock(ip, XFS_IOLOCK_EXCL);
+        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(
+        xfs_inode_t     *ip,
+        xfs_fsize_t     offset,
+        xfs_fsize_t     isize)
+{
+        xfs_fileoff_t   last_fsb;
+        xfs_mount_t     *mp = ip->i_mount;
+        int             nimaps;
+        int             zero_offset;
+        int             zero_len;
+        int             error = 0;
+        xfs_bmbt_irec_t imap;
+
+        ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
+
+        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(NULL, ip, 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(ip, XFS_ILOCK_EXCL);
+
+        zero_len = mp->m_sb.sb_blocksize - zero_offset;
+        if (isize + zero_len > offset)
+                zero_len = offset - isize;
+        error = xfs_iozero(ip, isize, zero_len);
+
+        xfs_ilock(ip, XFS_ILOCK_EXCL);
+        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(
+        xfs_inode_t     *ip,
+        xfs_off_t       offset,         /* starting I/O offset */
+        xfs_fsize_t     isize)          /* current inode size */
+{
+        xfs_mount_t     *mp = ip->i_mount;
+        xfs_fileoff_t   start_zero_fsb;
+        xfs_fileoff_t   end_zero_fsb;
+        xfs_fileoff_t   zero_count_fsb;
+        xfs_fileoff_t   last_fsb;
+        xfs_fileoff_t   zero_off;
+        xfs_fsize_t     zero_len;
+        int             nimaps;
+        int             error = 0;
+        xfs_bmbt_irec_t imap;
+
+        ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_IOLOCK_EXCL));
+        ASSERT(offset > isize);
+
+        /*
+         * 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, offset, isize);
+        if (error) {
+                ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_IOLOCK_EXCL));
+                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(NULL, ip, start_zero_fsb, zero_count_fsb,
+                                  0, NULL, 0, &imap, &nimaps, NULL, NULL);
+                if (error) {
+                        ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_IOLOCK_EXCL));
+                        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(ip, XFS_ILOCK_EXCL);
+
+                zero_off = XFS_FSB_TO_B(mp, start_zero_fsb);
+                zero_len = XFS_FSB_TO_B(mp, imap.br_blockcount);
+
+                if ((zero_off + zero_len) > offset)
+                        zero_len = offset - zero_off;
+
+                error = xfs_iozero(ip, zero_off, zero_len);
+                if (error) {
+                        goto out_lock;
+                }
+
+                start_zero_fsb = imap.br_startoff + imap.br_blockcount;
+                ASSERT(start_zero_fsb <= (end_zero_fsb + 1));
+
+                xfs_ilock(ip, XFS_ILOCK_EXCL);
+        }
+
+        return 0;
+
+out_lock:
+        xfs_ilock(ip, XFS_ILOCK_EXCL);
+        ASSERT(error >= 0);
+        return error;
+}
+
+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;
+        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;
+        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;
+                need_i_mutex = 0;
+        } else {
+                iolock = XFS_IOLOCK_EXCL;
+                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, xip,
+                                      pos, count, dmflags, &iolock);
+                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 && (mapping->nrpages || pos > xip->i_size)) {
+                        xfs_iunlock(xip, XFS_ILOCK_EXCL|iolock);
+                        iolock = XFS_IOLOCK_EXCL;
+                        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);
+
+        /*
+         * 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.
+         */
+        error = -file_remove_suid(file);
+        if (unlikely(error))
+                goto out_unlock_internal;
+
+        /* We can write back this queue in page reclaim */
+        current->backing_dev_info = mapping->backing_dev_info;
+
+        if ((ioflags & IO_ISDIRECT)) {
+                if (mapping->nrpages) {
+                        WARN_ON(need_i_mutex == 0);
+                        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;
+                        need_i_mutex = 0;
+                }
+
+                trace_xfs_file_direct_write(xip, count, *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 {
+                int enospc = 0;
+                ssize_t ret2 = 0;
+
+write_retry:
+                trace_xfs_file_buffered_write(xip, count, *offset, ioflags);
+                ret2 = generic_file_buffered_write(iocb, iovp, segs,
+                                pos, offset, count, ret);
+                /*
+                 * if we just got an ENOSPC, flush the inode now we
+                 * aren't holding any page locks and retry *once*
+                 */
+                if (ret2 == -ENOSPC && !enospc) {
+                        error = xfs_flush_pages(xip, 0, -1, 0, FI_NONE);
+                        if (error)
+                                goto out_unlock_internal;
+                        enospc = 1;
+                        goto write_retry;
+                }
+                ret = ret2;
+        }
+
+        current->backing_dev_info = NULL;
+
+        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);
+        }
+
+        if (ret == -ENOSPC &&
+            DM_EVENT_ENABLED(xip, DM_EVENT_NOSPACE) && !(ioflags & IO_INVIS)) {
+                xfs_iunlock(xip, iolock);
+                if (need_i_mutex)
+                        mutex_unlock(&inode->i_mutex);
+                error = XFS_SEND_NAMESP(xip->i_mount, DM_EVENT_NOSPACE, xip,
+                                DM_RIGHT_NULL, xip, DM_RIGHT_NULL, NULL, NULL,
+                                0, 0, 0); /* Delay flag intentionally  unused */
+                if (need_i_mutex)
+                        mutex_lock(&inode->i_mutex);
+                xfs_ilock(xip, iolock);
+                if (error)
+                        goto out_unlock_internal;
+                goto start;
+        }
+
+        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_DSYNC) || IS_SYNC(inode)) {
+                loff_t end = pos + ret - 1;
+                int error2;
+
+                xfs_iunlock(xip, iolock);
+                if (need_i_mutex)
+                        mutex_unlock(&inode->i_mutex);
+
+                error2 = filemap_write_and_wait_range(mapping, pos, end);
+                if (!error)
+                        error = error2;
+                if (need_i_mutex)
+                        mutex_lock(&inode->i_mutex);
+                xfs_ilock(xip, iolock);
+
+                error2 = xfs_fsync(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_iunlock(xip, iolock);
+ out_unlock_mutex:
+        if (need_i_mutex)
+                mutex_unlock(&inode->i_mutex);
+        return -error;
+}
+
 STATIC ssize_t
 xfs_file_aio_read(
         struct kiocb            *iocb,