1 files changed, 51 insertions, 133 deletions

diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index f675f3d9d7b3..7e5bc872f2b4 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -327,7 +327,7 @@ xfs_file_aio_read(
                                 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)
+                        if (iocb->ki_pos == i_size_read(inode))
                                 return 0;
                         return -XFS_ERROR(EINVAL);
                 }
@@ -412,51 +412,6 @@ xfs_file_splice_read(
         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,
-        xfs_fsize_t             new_size)
-{
-        if (new_size == ip->i_new_size) {
-                xfs_rw_ilock(ip, XFS_ILOCK_EXCL);
-                if (new_size == ip->i_new_size)
-                        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,
@@ -475,7 +430,6 @@ xfs_file_splice_write(
 {
         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;
 
@@ -489,19 +443,12 @@ xfs_file_splice_write(
 
         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);
+        if (ret > 0)
+                XFS_STATS_ADD(xs_write_bytes, ret);
 
-        xfs_aio_write_isize_update(inode, ppos, ret);
-        xfs_aio_write_newsize_update(ip, new_size);
         xfs_iunlock(ip, XFS_IOLOCK_EXCL);
         return ret;
 }
@@ -689,28 +636,26 @@ out_lock:
 /*
  * Common pre-write limit and setup checks.
  *
- * Returns with iolock held according to @iolock.
+ * Called with the iolocked held either shared and exclusive according to
+ * @iolock, and returns with it held.  Might upgrade the iolock to exclusive
+ * if called for a direct write beyond i_size.
  */
 STATIC ssize_t
 xfs_file_aio_write_checks(
         struct file             *file,
         loff_t                  *pos,
         size_t                  *count,
-        xfs_fsize_t             *new_sizep,
         int                     *iolock)
 {
         struct inode            *inode = file->f_mapping->host;
         struct xfs_inode        *ip = XFS_I(inode);
-        xfs_fsize_t             new_size;
         int                     error = 0;
 
         xfs_rw_ilock(ip, XFS_ILOCK_EXCL);
-        *new_sizep = 0;
 restart:
         error = generic_write_checks(file, pos, count, S_ISBLK(inode->i_mode));
         if (error) {
-                xfs_rw_iunlock(ip, XFS_ILOCK_EXCL | *iolock);
-                *iolock = 0;
+                xfs_rw_iunlock(ip, XFS_ILOCK_EXCL);
                 return error;
         }
 
@@ -720,36 +665,21 @@ restart:
         /*
          * 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. There is no need to issue zeroing if another in-flght IO ends
-         * at or before this one If zeronig is needed and we are currently
-         * holding the iolock shared, we need to update it to exclusive which
-         * involves dropping all locks and relocking to maintain correct locking
-         * order. If we do this, restart the function to ensure all checks and
-         * values are still valid.
+         * write.  If zeroing is needed and we are currently holding the
+         * iolock shared, we need to update it to exclusive which involves
+         * dropping all locks and relocking to maintain correct locking order.
+         * If we do this, restart the function to ensure all checks and values
+         * are still valid.
          */
-        if ((ip->i_new_size && *pos > ip->i_new_size) ||
-            (!ip->i_new_size && *pos > ip->i_size)) {
+        if (*pos > i_size_read(inode)) {
                 if (*iolock == XFS_IOLOCK_SHARED) {
                         xfs_rw_iunlock(ip, XFS_ILOCK_EXCL | *iolock);
                         *iolock = XFS_IOLOCK_EXCL;
                         xfs_rw_ilock(ip, XFS_ILOCK_EXCL | *iolock);
                         goto restart;
                 }
-                error = -xfs_zero_eof(ip, *pos, ip->i_size);
+                error = -xfs_zero_eof(ip, *pos, i_size_read(inode));
         }
-
-        /*
-         * If this IO extends beyond EOF, we may need to update ip->i_new_size.
-         * We have already zeroed space beyond EOF (if necessary).  Only update
-         * ip->i_new_size if this IO ends beyond any other in-flight writes.
-         */
-        new_size = *pos + *count;
-        if (new_size > ip->i_size) {
-                if (new_size > ip->i_new_size)
-                        ip->i_new_size = new_size;
-                *new_sizep = new_size;
-        }
-
         xfs_rw_iunlock(ip, XFS_ILOCK_EXCL);
         if (error)
                 return error;
@@ -794,9 +724,7 @@ xfs_file_dio_aio_write(
         const struct iovec      *iovp,
         unsigned long           nr_segs,
         loff_t                  pos,
-        size_t                  ocount,
-        xfs_fsize_t             *new_size,
-        int                     *iolock)
+        size_t                  ocount)
 {
         struct file             *file = iocb->ki_filp;
         struct address_space    *mapping = file->f_mapping;
@@ -806,10 +734,10 @@ xfs_file_dio_aio_write(
         ssize_t                 ret = 0;
         size_t                  count = ocount;
         int                     unaligned_io = 0;
+        int                     iolock;
         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);
 
@@ -824,31 +752,31 @@ xfs_file_dio_aio_write(
          * EOF zeroing cases and fill out the new inode size as appropriate.
          */
         if (unaligned_io || mapping->nrpages)
-                *iolock = XFS_IOLOCK_EXCL;
+                iolock = XFS_IOLOCK_EXCL;
         else
-                *iolock = XFS_IOLOCK_SHARED;
-        xfs_rw_ilock(ip, *iolock);
+                iolock = XFS_IOLOCK_SHARED;
+        xfs_rw_ilock(ip, iolock);
 
         /*
          * Recheck if there are cached pages that need invalidate after we got
          * the iolock to protect against other threads adding new pages while
          * we were waiting for the iolock.
          */
-        if (mapping->nrpages && *iolock == XFS_IOLOCK_SHARED) {
-                xfs_rw_iunlock(ip, *iolock);
-                *iolock = XFS_IOLOCK_EXCL;
-                xfs_rw_ilock(ip, *iolock);
+        if (mapping->nrpages && iolock == XFS_IOLOCK_SHARED) {
+                xfs_rw_iunlock(ip, iolock);
+                iolock = XFS_IOLOCK_EXCL;
+                xfs_rw_ilock(ip, iolock);
         }
 
-        ret = xfs_file_aio_write_checks(file, &pos, &count, new_size, iolock);
+        ret = xfs_file_aio_write_checks(file, &pos, &count, &iolock);
         if (ret)
-                return ret;
+                goto out;
 
         if (mapping->nrpages) {
                 ret = -xfs_flushinval_pages(ip, (pos & PAGE_CACHE_MASK), -1,
                                                         FI_REMAPF_LOCKED);
                 if (ret)
-                        return ret;
+                        goto out;
         }
 
         /*
@@ -857,15 +785,18 @@ xfs_file_dio_aio_write(
          */
         if (unaligned_io)
                 inode_dio_wait(inode);
-        else if (*iolock == XFS_IOLOCK_EXCL) {
+        else if (iolock == XFS_IOLOCK_EXCL) {
                 xfs_rw_ilock_demote(ip, XFS_IOLOCK_EXCL);
-                *iolock = XFS_IOLOCK_SHARED;
+                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);
 
+out:
+        xfs_rw_iunlock(ip, iolock);
+
         /* No fallback to buffered IO on errors for XFS. */
         ASSERT(ret < 0 || ret == count);
         return ret;
@@ -877,9 +808,7 @@ xfs_file_buffered_aio_write(
         const struct iovec      *iovp,
         unsigned long           nr_segs,
         loff_t                  pos,
-        size_t                  ocount,
-        xfs_fsize_t             *new_size,
-        int                     *iolock)
+        size_t                  ocount)
 {
         struct file             *file = iocb->ki_filp;
         struct address_space    *mapping = file->f_mapping;
@@ -887,14 +816,14 @@ xfs_file_buffered_aio_write(
         struct xfs_inode        *ip = XFS_I(inode);
         ssize_t                 ret;
         int                     enospc = 0;
+        int                     iolock = XFS_IOLOCK_EXCL;
         size_t                  count = ocount;
 
-        *iolock = XFS_IOLOCK_EXCL;
-        xfs_rw_ilock(ip, *iolock);
+        xfs_rw_ilock(ip, iolock);
 
-        ret = xfs_file_aio_write_checks(file, &pos, &count, new_size, iolock);
+        ret = xfs_file_aio_write_checks(file, &pos, &count, &iolock);
         if (ret)
-                return ret;
+                goto out;
 
         /* We can write back this queue in page reclaim */
         current->backing_dev_info = mapping->backing_dev_info;
@@ -908,13 +837,15 @@ write_retry:
          * 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;
+                ret = -xfs_flush_pages(ip, 0, -1, 0, FI_NONE);
+                if (!ret)
+                        goto write_retry;
         }
+
         current->backing_dev_info = NULL;
+out:
+        xfs_rw_iunlock(ip, iolock);
         return ret;
 }
 
@@ -930,9 +861,7 @@ xfs_file_aio_write(
         struct inode            *inode = mapping->host;
         struct xfs_inode        *ip = XFS_I(inode);
         ssize_t                 ret;
-        int                     iolock;
         size_t                  ocount = 0;
-        xfs_fsize_t             new_size = 0;
 
         XFS_STATS_INC(xs_write_calls);
 
@@ -951,33 +880,22 @@ xfs_file_aio_write(
                 return -EIO;
 
         if (unlikely(file->f_flags & O_DIRECT))
-                ret = xfs_file_dio_aio_write(iocb, iovp, nr_segs, pos,
-                                                ocount, &new_size, &iolock);
+                ret = xfs_file_dio_aio_write(iocb, iovp, nr_segs, pos, ocount);
         else
                 ret = xfs_file_buffered_aio_write(iocb, iovp, nr_segs, pos,
-                                                ocount, &new_size, &iolock);
-
-        xfs_aio_write_isize_update(inode, &iocb->ki_pos, ret);
+                                                  ocount);
 
-        if (ret <= 0)
-                goto out_unlock;
+        if (ret > 0) {
+                ssize_t err;
 
-        /* Handle various SYNC-type writes */
-        if ((file->f_flags & O_DSYNC) || IS_SYNC(inode)) {
-                loff_t end = pos + ret - 1;
-                int error;
+                XFS_STATS_ADD(xs_write_bytes, ret);
 
-                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;
+                /* Handle various SYNC-type writes */
+                err = generic_write_sync(file, pos, ret);
+                if (err < 0)
+                        ret = err;
         }
 
-out_unlock:
-        xfs_aio_write_newsize_update(ip, new_size);
-        xfs_rw_iunlock(ip, iolock);
         return ret;
 }