mm: move common segment checks to separate helper function

[akpm@linux-foundation.org: cleanup]
Signed-off-by: Monakhov Dmitriy <dmonakhov@openvz.org>
Cc: Christoph Hellwig <hch@lst.de>
Acked-by: Anton Altaparmakov <aia21@cam.ac.uk>
Acked-by: David Chinner <dgc@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 6 insertions, 37 deletions

diff --git a/fs/ntfs/file.c b/fs/ntfs/file.c
index dbbac5593106..621de369e6f8 100644
--- a/fs/ntfs/file.c
+++ b/fs/ntfs/file.c
@@ -2129,28 +2129,13 @@ static ssize_t ntfs_file_aio_write_nolock(struct kiocb *iocb,
         struct address_space *mapping = file->f_mapping;
         struct inode *inode = mapping->host;
         loff_t pos;
-        unsigned long seg;
         size_t count;           /* after file limit checks */
         ssize_t written, err;
 
         count = 0;
-        for (seg = 0; seg < nr_segs; seg++) {
-                const struct iovec *iv = &iov[seg];
-                /*
-                 * If any segment has a negative length, or the cumulative
-                 * length ever wraps negative then return -EINVAL.
-                 */
-                count += iv->iov_len;
-                if (unlikely((ssize_t)(count|iv->iov_len) < 0))
-                        return -EINVAL;
-                if (access_ok(VERIFY_READ, iv->iov_base, iv->iov_len))
-                        continue;
-                if (!seg)
-                        return -EFAULT;
-                nr_segs = seg;
-                count -= iv->iov_len;   /* This segment is no good */
-                break;
-        }
+        err = generic_segment_checks(iov, &nr_segs, &count, VERIFY_READ);
+        if (err)
+                return err;
         pos = *ppos;
         vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE);
         /* We can write back this queue in page reclaim. */
diff --git a/fs/xfs/linux-2.6/xfs_lrw.c b/fs/xfs/linux-2.6/xfs_lrw.c
index ff8d64eba9f8..558076dd0752 100644
--- a/fs/xfs/linux-2.6/xfs_lrw.c
+++ b/fs/xfs/linux-2.6/xfs_lrw.c
@@ -639,7 +639,6 @@ xfs_write(
         xfs_fsize_t             isize, new_size;
         xfs_iocore_t            *io;
         bhv_vnode_t             *vp;
-        unsigned long           seg;
         int                     iolock;
         int                     eventsent = 0;
         bhv_vrwlock_t           locktype;
@@ -652,24 +651,9 @@ xfs_write(
         vp = BHV_TO_VNODE(bdp);
         xip = XFS_BHVTOI(bdp);
 
-        for (seg = 0; seg < segs; seg++) {
-                const struct iovec *iv = &iovp[seg];
-
-                /*
-                 * If any segment has a negative length, or the cumulative
-                 * length ever wraps negative then return -EINVAL.
-                 */
-                ocount += iv->iov_len;
-                if (unlikely((ssize_t)(ocount|iv->iov_len) < 0))
-                        return -EINVAL;
-                if (access_ok(VERIFY_READ, iv->iov_base, iv->iov_len))
-                        continue;
-                if (seg == 0)
-                        return -EFAULT;
-                segs = seg;
-                ocount -= iv->iov_len;  /* This segment is no good */
-                break;
-        }
+        error = generic_segment_checks(iovp, &segs, &ocount, VERIFY_READ);
+        if (error)
+                return error;
 
         count = ocount;
         pos = *offset;