xfs: remove subdirectories

Use the move from Linux 2.6 to Linux 3.x as an excuse to kill the
annoying subdirectories in the XFS source code.  Besides the large
amount of file rename the only changes are to the Makefile, a few
files including headers with the subdirectory prefix, and the binary
sysctl compat code that includes a header under fs/xfs/ from
kernel/.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>

1 files changed, 1096 insertions, 0 deletions

diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
new file mode 100644
index 000000000000..7f7b42469ea7
--- /dev/null
+++ b/fs/xfs/xfs_file.c
@@ -0,0 +1,1096 @@
+/*
+ * Copyright (c) 2000-2005 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_sb.h"
+#include "xfs_ag.h"
+#include "xfs_trans.h"
+#include "xfs_mount.h"
+#include "xfs_bmap_btree.h"
+#include "xfs_alloc.h"
+#include "xfs_dinode.h"
+#include "xfs_inode.h"
+#include "xfs_inode_item.h"
+#include "xfs_bmap.h"
+#include "xfs_error.h"
+#include "xfs_vnodeops.h"
+#include "xfs_da_btree.h"
+#include "xfs_ioctl.h"
+#include "xfs_trace.h"
+
+#include <linux/dcache.h>
+#include <linux/falloc.h>
+
+static const struct vm_operations_struct xfs_file_vm_ops;
+
+/*
+ * Locking primitives for read and write IO paths to ensure we consistently use
+ * and order the inode->i_mutex, ip->i_lock and ip->i_iolock.
+ */
+static inline void
+xfs_rw_ilock(
+        struct xfs_inode        *ip,
+        int                     type)
+{
+        if (type & XFS_IOLOCK_EXCL)
+                mutex_lock(&VFS_I(ip)->i_mutex);
+        xfs_ilock(ip, type);
+}
+
+static inline void
+xfs_rw_iunlock(
+        struct xfs_inode        *ip,
+        int                     type)
+{
+        xfs_iunlock(ip, type);
+        if (type & XFS_IOLOCK_EXCL)
+                mutex_unlock(&VFS_I(ip)->i_mutex);
+}
+
+static inline void
+xfs_rw_ilock_demote(
+        struct xfs_inode        *ip,
+        int                     type)
+{
+        xfs_ilock_demote(ip, type);
+        if (type & XFS_IOLOCK_EXCL)
+                mutex_unlock(&VFS_I(ip)->i_mutex);
+}
+
+/*
+ *      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);
+}
+
+STATIC int
+xfs_file_fsync(
+        struct file             *file,
+        loff_t                  start,
+        loff_t                  end,
+        int                     datasync)
+{
+        struct inode            *inode = file->f_mapping->host;
+        struct xfs_inode        *ip = XFS_I(inode);
+        struct xfs_mount        *mp = ip->i_mount;
+        struct xfs_trans        *tp;
+        int                     error = 0;
+        int                     log_flushed = 0;
+
+        trace_xfs_file_fsync(ip);
+
+        error = filemap_write_and_wait_range(inode->i_mapping, start, end);
+        if (error)
+                return error;
+
+        if (XFS_FORCED_SHUTDOWN(mp))
+                return -XFS_ERROR(EIO);
+
+        xfs_iflags_clear(ip, XFS_ITRUNCATED);
+
+        xfs_ilock(ip, XFS_IOLOCK_SHARED);
+        xfs_ioend_wait(ip);
+        xfs_iunlock(ip, XFS_IOLOCK_SHARED);
+
+        if (mp->m_flags & XFS_MOUNT_BARRIER) {
+                /*
+                 * If we have an RT and/or log subvolume we need to make sure
+                 * to flush the write cache the device used for file data
+                 * first.  This is to ensure newly written file data make
+                 * it to disk before logging the new inode size in case of
+                 * an extending write.
+                 */
+                if (XFS_IS_REALTIME_INODE(ip))
+                        xfs_blkdev_issue_flush(mp->m_rtdev_targp);
+                else if (mp->m_logdev_targp != mp->m_ddev_targp)
+                        xfs_blkdev_issue_flush(mp->m_ddev_targp);
+        }
+
+        /*
+         * We always need to make sure that the required inode state is safe on
+         * disk.  The inode might be clean but we still might need to force the
+         * log because of committed transactions that haven't hit the disk yet.
+         * Likewise, there could be unflushed non-transactional changes to the
+         * inode core that have to go to disk and this requires us to issue
+         * a synchronous transaction to capture these changes correctly.
+         *
+         * This code relies on the assumption that if the i_update_core field
+         * of the inode is clear and the inode is unpinned then it is clean
+         * and no action is required.
+         */
+        xfs_ilock(ip, XFS_ILOCK_SHARED);
+
+        /*
+         * First check if the VFS inode is marked dirty.  All the dirtying
+         * of non-transactional updates no goes through mark_inode_dirty*,
+         * which allows us to distinguish beteeen pure timestamp updates
+         * and i_size updates which need to be caught for fdatasync.
+         * After that also theck for the dirty state in the XFS inode, which
+         * might gets cleared when the inode gets written out via the AIL
+         * or xfs_iflush_cluster.
+         */
+        if (((inode->i_state & I_DIRTY_DATASYNC) ||
+            ((inode->i_state & I_DIRTY_SYNC) && !datasync)) &&
+            ip->i_update_core) {
+                /*
+                 * Kick off a transaction to log the inode core to get the
+                 * updates.  The sync transaction will also force the log.
+                 */
+                xfs_iunlock(ip, XFS_ILOCK_SHARED);
+                tp = xfs_trans_alloc(mp, XFS_TRANS_FSYNC_TS);
+                error = xfs_trans_reserve(tp, 0,
+                                XFS_FSYNC_TS_LOG_RES(mp), 0, 0, 0);
+                if (error) {
+                        xfs_trans_cancel(tp, 0);
+                        return -error;
+                }
+                xfs_ilock(ip, XFS_ILOCK_EXCL);
+
+                /*
+                 * Note - it's possible that we might have pushed ourselves out
+                 * of the way during trans_reserve which would flush the inode.
+                 * But there's no guarantee that the inode buffer has actually
+                 * gone out yet (it's delwri).  Plus the buffer could be pinned
+                 * anyway if it's part of an inode in another recent
+                 * transaction.  So we play it safe and fire off the
+                 * transaction anyway.
+                 */
+                xfs_trans_ijoin(tp, ip);
+                xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
+                xfs_trans_set_sync(tp);
+                error = _xfs_trans_commit(tp, 0, &log_flushed);
+
+                xfs_iunlock(ip, XFS_ILOCK_EXCL);
+        } else {
+                /*
+                 * Timestamps/size haven't changed since last inode flush or
+                 * inode transaction commit.  That means either nothing got
+                 * written or a transaction committed which caught the updates.
+                 * If the latter happened and the transaction hasn't hit the
+                 * disk yet, the inode will be still be pinned.  If it is,
+                 * force the log.
+                 */
+                if (xfs_ipincount(ip)) {
+                        error = _xfs_log_force_lsn(mp,
+                                        ip->i_itemp->ili_last_lsn,
+                                        XFS_LOG_SYNC, &log_flushed);
+                }
+                xfs_iunlock(ip, XFS_ILOCK_SHARED);
+        }
+
+        /*
+         * If we only have a single device, and the log force about was
+         * a no-op we might have to flush the data device cache here.
+         * This can only happen for fdatasync/O_DSYNC if we were overwriting
+         * an already allocated file and thus do not have any metadata to
+         * commit.
+         */
+        if ((mp->m_flags & XFS_MOUNT_BARRIER) &&
+            mp->m_logdev_targp == mp->m_ddev_targp &&
+            !XFS_IS_REALTIME_INODE(ip) &&
+            !log_flushed)
+                xfs_blkdev_issue_flush(mp->m_ddev_targp);
+
+        return -error;
+}
+
+STATIC ssize_t
+xfs_file_aio_read(
+        struct kiocb            *iocb,
+        const struct iovec      *iovp,
+        unsigned long           nr_segs,
+        loff_t                  pos)
+{
+        struct file             *file = iocb->ki_filp;
+        struct inode            *inode = file->f_mapping->host;
+        struct xfs_inode        *ip = XFS_I(inode);
+        struct xfs_mount        *mp = ip->i_mount;
+        size_t                  size = 0;
+        ssize_t                 ret = 0;
+        int                     ioflags = 0;
+        xfs_fsize_t             n;
+        unsigned long           seg;
+
+        XFS_STATS_INC(xs_read_calls);
+
+        BUG_ON(iocb->ki_pos != pos);
+
+        if (unlikely(file->f_flags & O_DIRECT))
+                ioflags |= IO_ISDIRECT;
+        if (file->f_mode & FMODE_NOCMTIME)
+                ioflags |= IO_INVIS;
+
+        /* START copy & waste from filemap.c */
+        for (seg = 0; seg < nr_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 ((iocb->ki_pos & target->bt_smask) ||
+                    (size & target->bt_smask)) {
+                        if (iocb->ki_pos == ip->i_size)
+                                return 0;
+                        return -XFS_ERROR(EINVAL);
+                }
+        }
+
+        n = XFS_MAXIOFFSET(mp) - iocb->ki_pos;
+        if (n <= 0 || size == 0)
+                return 0;
+
+        if (n < size)
+                size = n;
+
+        if (XFS_FORCED_SHUTDOWN(mp))
+                return -EIO;
+
+        if (unlikely(ioflags & IO_ISDIRECT)) {
+                xfs_rw_ilock(ip, XFS_IOLOCK_EXCL);
+
+                if (inode->i_mapping->nrpages) {
+                        ret = -xfs_flushinval_pages(ip,
+                                        (iocb->ki_pos & PAGE_CACHE_MASK),
+                                        -1, FI_REMAPF_LOCKED);
+                        if (ret) {
+                                xfs_rw_iunlock(ip, XFS_IOLOCK_EXCL);
+                                return ret;
+                        }
+                }
+                xfs_rw_ilock_demote(ip, XFS_IOLOCK_EXCL);
+        } else
+                xfs_rw_ilock(ip, XFS_IOLOCK_SHARED);
+
+        trace_xfs_file_read(ip, size, iocb->ki_pos, ioflags);
+
+        ret = generic_file_aio_read(iocb, iovp, nr_segs, iocb->ki_pos);
+        if (ret > 0)
+                XFS_STATS_ADD(xs_read_bytes, ret);
+
+        xfs_rw_iunlock(ip, XFS_IOLOCK_SHARED);
+        return ret;
+}
+
+STATIC ssize_t
+xfs_file_splice_read(
+        struct file             *infilp,
+        loff_t                  *ppos,
+        struct pipe_inode_info  *pipe,
+        size_t                  count,
+        unsigned int            flags)
+{
+        struct xfs_inode        *ip = XFS_I(infilp->f_mapping->host);
+        int                     ioflags = 0;
+        ssize_t                 ret;
+
+        XFS_STATS_INC(xs_read_calls);
+
+        if (infilp->f_mode & FMODE_NOCMTIME)
+                ioflags |= IO_INVIS;
+
+        if (XFS_FORCED_SHUTDOWN(ip->i_mount))
+                return -EIO;
+
+        xfs_rw_ilock(ip, XFS_IOLOCK_SHARED);
+
+        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_rw_iunlock(ip, XFS_IOLOCK_SHARED);
+        return ret;
+}
+
+STATIC void
+xfs_aio_write_isize_update(
+        struct inode    *inode,
+        loff_t          *ppos,
+        ssize_t         bytes_written)
+{
+        struct xfs_inode        *ip = XFS_I(inode);
+        xfs_fsize_t             isize = i_size_read(inode);
+
+        if (bytes_written > 0)
+                XFS_STATS_ADD(xs_write_bytes, bytes_written);
+
+        if (unlikely(bytes_written < 0 && bytes_written != -EFAULT &&
+                                        *ppos > isize))
+                *ppos = isize;
+
+        if (*ppos > ip->i_size) {
+                xfs_rw_ilock(ip, XFS_ILOCK_EXCL);
+                if (*ppos > ip->i_size)
+                        ip->i_size = *ppos;
+                xfs_rw_iunlock(ip, XFS_ILOCK_EXCL);
+        }
+}
+
+/*
+ * 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 occurred.  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.
+ */
+STATIC void
+xfs_aio_write_newsize_update(
+        struct xfs_inode        *ip)
+{
+        if (ip->i_new_size) {
+                xfs_rw_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_rw_iunlock(ip, XFS_ILOCK_EXCL);
+        }
+}
+
+/*
+ * xfs_file_splice_write() does not use xfs_rw_ilock() because
+ * generic_file_splice_write() takes the i_mutex itself. This, in theory,
+ * couuld cause lock inversions between the aio_write path and the splice path
+ * if someone is doing concurrent splice(2) based writes and write(2) based
+ * writes to the same inode. The only real way to fix this is to re-implement
+ * the generic code here with correct locking orders.
+ */
+STATIC ssize_t
+xfs_file_splice_write(
+        struct pipe_inode_info  *pipe,
+        struct file             *outfilp,
+        loff_t                  *ppos,
+        size_t                  count,
+        unsigned int            flags)
+{
+        struct inode            *inode = outfilp->f_mapping->host;
+        struct xfs_inode        *ip = XFS_I(inode);
+        xfs_fsize_t             new_size;
+        int                     ioflags = 0;
+        ssize_t                 ret;
+
+        XFS_STATS_INC(xs_write_calls);
+
+        if (outfilp->f_mode & FMODE_NOCMTIME)
+                ioflags |= IO_INVIS;
+
+        if (XFS_FORCED_SHUTDOWN(ip->i_mount))
+                return -EIO;
+
+        xfs_ilock(ip, XFS_IOLOCK_EXCL);
+
+        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);
+
+        xfs_aio_write_isize_update(inode, ppos, ret);
+        xfs_aio_write_newsize_update(ip);
+        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);
+        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);
+                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;
+}
+
+/*
+ * Common pre-write limit and setup checks.
+ *
+ * Returns with iolock held according to @iolock.
+ */
+STATIC ssize_t
+xfs_file_aio_write_checks(
+        struct file             *file,
+        loff_t                  *pos,
+        size_t                  *count,
+        int                     *iolock)
+{
+        struct inode            *inode = file->f_mapping->host;
+        struct xfs_inode        *ip = XFS_I(inode);
+        xfs_fsize_t             new_size;
+        int                     error = 0;
+
+        error = generic_write_checks(file, pos, count, S_ISBLK(inode->i_mode));
+        if (error) {
+                xfs_rw_iunlock(ip, XFS_ILOCK_EXCL | *iolock);
+                *iolock = 0;
+                return error;
+        }
+
+        new_size = *pos + *count;
+        if (new_size > ip->i_size)
+                ip->i_new_size = new_size;
+
+        if (likely(!(file->f_mode & FMODE_NOCMTIME)))
+                file_update_time(file);
+
+        /*
+         * If the offset is beyond the size of the file, we need to zero any
+         * blocks that fall between the existing EOF and the start of this
+         * write.
+         */
+        if (*pos > ip->i_size)
+                error = -xfs_zero_eof(ip, *pos, ip->i_size);
+
+        xfs_rw_iunlock(ip, XFS_ILOCK_EXCL);
+        if (error)
+                return error;
+
+        /*
+         * 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.
+         */
+        return file_remove_suid(file);
+
+}
+
+/*
+ * xfs_file_dio_aio_write - handle direct IO writes
+ *
+ * Lock the inode appropriately to prepare for and issue a direct IO write.
+ * By separating it from the buffered write path we remove all the tricky to
+ * follow locking changes and looping.
+ *
+ * If there are cached pages or we're extending the file, we need IOLOCK_EXCL
+ * until we're sure the bytes at the new EOF have been zeroed and/or the cached
+ * pages are flushed out.
+ *
+ * In most cases the direct IO writes will be done holding IOLOCK_SHARED
+ * allowing them to be done in parallel with reads and other direct IO writes.
+ * However, if the IO is not aligned to filesystem blocks, the direct IO layer
+ * needs to do sub-block zeroing and that requires serialisation against other
+ * direct IOs to the same block. In this case we need to serialise the
+ * submission of the unaligned IOs so that we don't get racing block zeroing in
+ * the dio layer.  To avoid the problem with aio, we also need to wait for
+ * outstanding IOs to complete so that unwritten extent conversion is completed
+ * before we try to map the overlapping block. This is currently implemented by
+ * hitting it with a big hammer (i.e. xfs_ioend_wait()).
+ *
+ * Returns with locks held indicated by @iolock and errors indicated by
+ * negative return values.
+ */
+STATIC ssize_t
+xfs_file_dio_aio_write(
+        struct kiocb            *iocb,
+        const struct iovec      *iovp,
+        unsigned long           nr_segs,
+        loff_t                  pos,
+        size_t                  ocount,
+        int                     *iolock)
+{
+        struct file             *file = iocb->ki_filp;
+        struct address_space    *mapping = file->f_mapping;
+        struct inode            *inode = mapping->host;
+        struct xfs_inode        *ip = XFS_I(inode);
+        struct xfs_mount        *mp = ip->i_mount;
+        ssize_t                 ret = 0;
+        size_t                  count = ocount;
+        int                     unaligned_io = 0;
+        struct xfs_buftarg      *target = XFS_IS_REALTIME_INODE(ip) ?
+                                        mp->m_rtdev_targp : mp->m_ddev_targp;
+
+        *iolock = 0;
+        if ((pos & target->bt_smask) || (count & target->bt_smask))
+                return -XFS_ERROR(EINVAL);
+
+        if ((pos & mp->m_blockmask) || ((pos + count) & mp->m_blockmask))
+                unaligned_io = 1;
+
+        if (unaligned_io || mapping->nrpages || pos > ip->i_size)
+                *iolock = XFS_IOLOCK_EXCL;
+        else
+                *iolock = XFS_IOLOCK_SHARED;
+        xfs_rw_ilock(ip, XFS_ILOCK_EXCL | *iolock);
+
+        ret = xfs_file_aio_write_checks(file, &pos, &count, iolock);
+        if (ret)
+                return ret;
+
+        if (mapping->nrpages) {
+                WARN_ON(*iolock != XFS_IOLOCK_EXCL);
+                ret = -xfs_flushinval_pages(ip, (pos & PAGE_CACHE_MASK), -1,
+                                                        FI_REMAPF_LOCKED);
+                if (ret)
+                        return ret;
+        }
+
+        /*
+         * If we are doing unaligned IO, wait for all other IO to drain,
+         * otherwise demote the lock if we had to flush cached pages
+         */
+        if (unaligned_io)
+                xfs_ioend_wait(ip);
+        else if (*iolock == XFS_IOLOCK_EXCL) {
+                xfs_rw_ilock_demote(ip, XFS_IOLOCK_EXCL);
+                *iolock = XFS_IOLOCK_SHARED;
+        }
+
+        trace_xfs_file_direct_write(ip, count, iocb->ki_pos, 0);
+        ret = generic_file_direct_write(iocb, iovp,
+                        &nr_segs, pos, &iocb->ki_pos, count, ocount);
+
+        /* No fallback to buffered IO on errors for XFS. */
+        ASSERT(ret < 0 || ret == count);
+        return ret;
+}
+
+STATIC ssize_t
+xfs_file_buffered_aio_write(
+        struct kiocb            *iocb,
+        const struct iovec      *iovp,
+        unsigned long           nr_segs,
+        loff_t                  pos,
+        size_t                  ocount,
+        int                     *iolock)
+{
+        struct file             *file = iocb->ki_filp;
+        struct address_space    *mapping = file->f_mapping;
+        struct inode            *inode = mapping->host;
+        struct xfs_inode        *ip = XFS_I(inode);
+        ssize_t                 ret;
+        int                     enospc = 0;
+        size_t                  count = ocount;
+
+        *iolock = XFS_IOLOCK_EXCL;
+        xfs_rw_ilock(ip, XFS_ILOCK_EXCL | *iolock);
+
+        ret = xfs_file_aio_write_checks(file, &pos, &count, iolock);
+        if (ret)
+                return ret;
+
+        /* We can write back this queue in page reclaim */
+        current->backing_dev_info = mapping->backing_dev_info;
+
+write_retry:
+        trace_xfs_file_buffered_write(ip, count, iocb->ki_pos, 0);
+        ret = generic_file_buffered_write(iocb, iovp, nr_segs,
+                        pos, &iocb->ki_pos, count, ret);
+        /*
+         * if we just got an ENOSPC, flush the inode now we aren't holding any
+         * page locks and retry *once*
+         */
+        if (ret == -ENOSPC && !enospc) {
+                ret = -xfs_flush_pages(ip, 0, -1, 0, FI_NONE);
+                if (ret)
+                        return ret;
+                enospc = 1;
+                goto write_retry;
+        }
+        current->backing_dev_info = NULL;
+        return ret;
+}
+
+STATIC ssize_t
+xfs_file_aio_write(
+        struct kiocb            *iocb,
+        const struct iovec      *iovp,
+        unsigned long           nr_segs,
+        loff_t                  pos)
+{
+        struct file             *file = iocb->ki_filp;
+        struct address_space    *mapping = file->f_mapping;
+        struct inode            *inode = mapping->host;
+        struct xfs_inode        *ip = XFS_I(inode);
+        ssize_t                 ret;
+        int                     iolock;
+        size_t                  ocount = 0;
+
+        XFS_STATS_INC(xs_write_calls);
+
+        BUG_ON(iocb->ki_pos != pos);
+
+        ret = generic_segment_checks(iovp, &nr_segs, &ocount, VERIFY_READ);
+        if (ret)
+                return ret;
+
+        if (ocount == 0)
+                return 0;
+
+        xfs_wait_for_freeze(ip->i_mount, SB_FREEZE_WRITE);
+
+        if (XFS_FORCED_SHUTDOWN(ip->i_mount))
+                return -EIO;
+
+        if (unlikely(file->f_flags & O_DIRECT))
+                ret = xfs_file_dio_aio_write(iocb, iovp, nr_segs, pos,
+                                                ocount, &iolock);
+        else
+                ret = xfs_file_buffered_aio_write(iocb, iovp, nr_segs, pos,
+                                                ocount, &iolock);
+
+        xfs_aio_write_isize_update(inode, &iocb->ki_pos, ret);
+
+        if (ret <= 0)
+                goto out_unlock;
+
+        /* Handle various SYNC-type writes */
+        if ((file->f_flags & O_DSYNC) || IS_SYNC(inode)) {
+                loff_t end = pos + ret - 1;
+                int error;
+
+                xfs_rw_iunlock(ip, iolock);
+                error = xfs_file_fsync(file, pos, end,
+                                      (file->f_flags & __O_SYNC) ? 0 : 1);
+                xfs_rw_ilock(ip, iolock);
+                if (error)
+                        ret = error;
+        }
+
+out_unlock:
+        xfs_aio_write_newsize_update(ip);
+        xfs_rw_iunlock(ip, iolock);
+        return ret;
+}
+
+STATIC long
+xfs_file_fallocate(
+        struct file     *file,
+        int             mode,
+        loff_t          offset,
+        loff_t          len)
+{
+        struct inode    *inode = file->f_path.dentry->d_inode;
+        long            error;
+        loff_t          new_size = 0;
+        xfs_flock64_t   bf;
+        xfs_inode_t     *ip = XFS_I(inode);
+        int             cmd = XFS_IOC_RESVSP;
+        int             attr_flags = XFS_ATTR_NOLOCK;
+
+        if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
+                return -EOPNOTSUPP;
+
+        bf.l_whence = 0;
+        bf.l_start = offset;
+        bf.l_len = len;
+
+        xfs_ilock(ip, XFS_IOLOCK_EXCL);
+
+        if (mode & FALLOC_FL_PUNCH_HOLE)
+                cmd = XFS_IOC_UNRESVSP;
+
+        /* check the new inode size is valid before allocating */
+        if (!(mode & FALLOC_FL_KEEP_SIZE) &&
+            offset + len > i_size_read(inode)) {
+                new_size = offset + len;
+                error = inode_newsize_ok(inode, new_size);
+                if (error)
+                        goto out_unlock;
+        }
+
+        if (file->f_flags & O_DSYNC)
+                attr_flags |= XFS_ATTR_SYNC;
+
+        error = -xfs_change_file_space(ip, cmd, &bf, 0, attr_flags);
+        if (error)
+                goto out_unlock;
+
+        /* Change file size if needed */
+        if (new_size) {
+                struct iattr iattr;
+
+                iattr.ia_valid = ATTR_SIZE;
+                iattr.ia_size = new_size;
+                error = -xfs_setattr_size(ip, &iattr, XFS_ATTR_NOLOCK);
+        }
+
+out_unlock:
+        xfs_iunlock(ip, XFS_IOLOCK_EXCL);
+        return error;
+}
+
+
+STATIC int
+xfs_file_open(
+        struct inode    *inode,
+        struct file     *file)
+{
+        if (!(file->f_flags & O_LARGEFILE) && i_size_read(inode) > MAX_NON_LFS)
+                return -EFBIG;
+        if (XFS_FORCED_SHUTDOWN(XFS_M(inode->i_sb)))
+                return -EIO;
+        return 0;
+}
+
+STATIC int
+xfs_dir_open(
+        struct inode    *inode,
+        struct file     *file)
+{
+        struct xfs_inode *ip = XFS_I(inode);
+        int             mode;
+        int             error;
+
+        error = xfs_file_open(inode, file);
+        if (error)
+                return error;
+
+        /*
+         * If there are any blocks, read-ahead block 0 as we're almost
+         * certain to have the next operation be a read there.
+         */
+        mode = xfs_ilock_map_shared(ip);
+        if (ip->i_d.di_nextents > 0)
+                xfs_da_reada_buf(NULL, ip, 0, XFS_DATA_FORK);
+        xfs_iunlock(ip, mode);
+        return 0;
+}
+
+STATIC int
+xfs_file_release(
+        struct inode    *inode,
+        struct file     *filp)
+{
+        return -xfs_release(XFS_I(inode));
+}
+
+STATIC int
+xfs_file_readdir(
+        struct file     *filp,
+        void            *dirent,
+        filldir_t       filldir)
+{
+        struct inode    *inode = filp->f_path.dentry->d_inode;
+        xfs_inode_t     *ip = XFS_I(inode);
+        int             error;
+        size_t          bufsize;
+
+        /*
+         * The Linux API doesn't pass down the total size of the buffer
+         * we read into down to the filesystem.  With the filldir concept
+         * it's not needed for correct information, but the XFS dir2 leaf
+         * code wants an estimate of the buffer size to calculate it's
+         * readahead window and size the buffers used for mapping to
+         * physical blocks.
+         *
+         * Try to give it an estimate that's good enough, maybe at some
+         * point we can change the ->readdir prototype to include the
+         * buffer size.  For now we use the current glibc buffer size.
+         */
+        bufsize = (size_t)min_t(loff_t, 32768, ip->i_d.di_size);
+
+        error = xfs_readdir(ip, dirent, bufsize,
+                                (xfs_off_t *)&filp->f_pos, filldir);
+        if (error)
+                return -error;
+        return 0;
+}
+
+STATIC int
+xfs_file_mmap(
+        struct file     *filp,
+        struct vm_area_struct *vma)
+{
+        vma->vm_ops = &xfs_file_vm_ops;
+        vma->vm_flags |= VM_CAN_NONLINEAR;
+
+        file_accessed(filp);
+        return 0;
+}
+
+/*
+ * mmap()d file has taken write protection fault and is being made
+ * writable. We can set the page state up correctly for a writable
+ * page, which means we can do correct delalloc accounting (ENOSPC
+ * checking!) and unwritten extent mapping.
+ */
+STATIC int
+xfs_vm_page_mkwrite(
+        struct vm_area_struct   *vma,
+        struct vm_fault         *vmf)
+{
+        return block_page_mkwrite(vma, vmf, xfs_get_blocks);
+}
+
+const struct file_operations xfs_file_operations = {
+        .llseek         = generic_file_llseek,
+        .read           = do_sync_read,
+        .write          = do_sync_write,
+        .aio_read       = xfs_file_aio_read,
+        .aio_write      = xfs_file_aio_write,
+        .splice_read    = xfs_file_splice_read,
+        .splice_write   = xfs_file_splice_write,
+        .unlocked_ioctl = xfs_file_ioctl,
+#ifdef CONFIG_COMPAT
+        .compat_ioctl   = xfs_file_compat_ioctl,
+#endif
+        .mmap           = xfs_file_mmap,
+        .open           = xfs_file_open,
+        .release        = xfs_file_release,
+        .fsync          = xfs_file_fsync,
+        .fallocate      = xfs_file_fallocate,
+};
+
+const struct file_operations xfs_dir_file_operations = {
+        .open           = xfs_dir_open,
+        .read           = generic_read_dir,
+        .readdir        = xfs_file_readdir,
+        .llseek         = generic_file_llseek,
+        .unlocked_ioctl = xfs_file_ioctl,
+#ifdef CONFIG_COMPAT
+        .compat_ioctl   = xfs_file_compat_ioctl,
+#endif
+        .fsync          = xfs_file_fsync,
+};
+
+static const struct vm_operations_struct xfs_file_vm_ops = {
+        .fault          = filemap_fault,
+        .page_mkwrite   = xfs_vm_page_mkwrite,
+};