gfs2: Pull return value test out of should_fault_in_pages
authorAndreas Gruenbacher <agruenba@redhat.com>
Thu, 5 May 2022 10:53:26 +0000 (12:53 +0200)
committerAndreas Gruenbacher <agruenba@redhat.com>
Fri, 13 May 2022 20:00:22 +0000 (22:00 +0200)
Pull the return value test of the previous read or write operation out
of should_fault_in_pages().  In a following patch, we'll fault in pages
before the I/O and there will be no return value to check.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
fs/gfs2/file.c

index acc0c1d..ea87bef 100644 (file)
@@ -770,7 +770,7 @@ static int gfs2_fsync(struct file *file, loff_t start, loff_t end,
        return ret ? ret : ret1;
 }
 
-static inline bool should_fault_in_pages(ssize_t ret, struct iov_iter *i,
+static inline bool should_fault_in_pages(struct iov_iter *i,
                                         size_t *prev_count,
                                         size_t *window_size)
 {
@@ -779,8 +779,6 @@ static inline bool should_fault_in_pages(ssize_t ret, struct iov_iter *i,
 
        if (likely(!count))
                return false;
-       if (ret <= 0 && ret != -EFAULT)
-               return false;
        if (!iter_is_iovec(i))
                return false;
 
@@ -842,10 +840,12 @@ retry_under_glock:
                           IOMAP_DIO_PARTIAL, read);
        to->nofault = false;
        pagefault_enable();
+       if (ret <= 0 && ret != -EFAULT)
+               goto out_unlock;
        if (ret > 0)
                read = ret;
 
-       if (should_fault_in_pages(ret, to, &prev_count, &window_size)) {
+       if (should_fault_in_pages(to, &prev_count, &window_size)) {
                gfs2_holder_allow_demote(gh);
                window_size -= fault_in_iov_iter_writeable(to, window_size);
                gfs2_holder_disallow_demote(gh);
@@ -855,6 +855,7 @@ retry_under_glock:
                        goto retry;
                }
        }
+out_unlock:
        if (gfs2_holder_queued(gh))
                gfs2_glock_dq(gh);
 out_uninit:
@@ -899,20 +900,23 @@ retry:
                goto out_uninit;
        /* Silently fall back to buffered I/O when writing beyond EOF */
        if (iocb->ki_pos + iov_iter_count(from) > i_size_read(&ip->i_inode))
-               goto out;
+               goto out_unlock;
 retry_under_glock:
 
        from->nofault = true;
        ret = iomap_dio_rw(iocb, from, &gfs2_iomap_ops, NULL,
                           IOMAP_DIO_PARTIAL, written);
        from->nofault = false;
-
-       if (ret == -ENOTBLK)
-               ret = 0;
+       if (ret <= 0) {
+               if (ret == -ENOTBLK)
+                       ret = 0;
+               if (ret != -EFAULT)
+                       goto out_unlock;
+       }
        if (ret > 0)
                written = ret;
 
-       if (should_fault_in_pages(ret, from, &prev_count, &window_size)) {
+       if (should_fault_in_pages(from, &prev_count, &window_size)) {
                gfs2_holder_allow_demote(gh);
                window_size -= fault_in_iov_iter_readable(from, window_size);
                gfs2_holder_disallow_demote(gh);
@@ -922,7 +926,7 @@ retry_under_glock:
                        goto retry;
                }
        }
-out:
+out_unlock:
        if (gfs2_holder_queued(gh))
                gfs2_glock_dq(gh);
 out_uninit:
@@ -975,10 +979,12 @@ retry_under_glock:
        pagefault_disable();
        ret = generic_file_read_iter(iocb, to);
        pagefault_enable();
+       if (ret <= 0 && ret != -EFAULT)
+               goto out_unlock;
        if (ret > 0)
                read += ret;
 
-       if (should_fault_in_pages(ret, to, &prev_count, &window_size)) {
+       if (should_fault_in_pages(to, &prev_count, &window_size)) {
                gfs2_holder_allow_demote(&gh);
                window_size -= fault_in_iov_iter_writeable(to, window_size);
                gfs2_holder_disallow_demote(&gh);
@@ -988,6 +994,7 @@ retry_under_glock:
                        goto retry;
                }
        }
+out_unlock:
        if (gfs2_holder_queued(&gh))
                gfs2_glock_dq(&gh);
 out_uninit:
@@ -1050,8 +1057,11 @@ retry_under_glock:
        if (inode == sdp->sd_rindex)
                gfs2_glock_dq_uninit(statfs_gh);
 
+       if (ret <= 0 && ret != -EFAULT)
+               goto out_unlock;
+
        from->count = orig_count - written;
-       if (should_fault_in_pages(ret, from, &prev_count, &window_size)) {
+       if (should_fault_in_pages(from, &prev_count, &window_size)) {
                gfs2_holder_allow_demote(gh);
                window_size -= fault_in_iov_iter_readable(from, window_size);
                gfs2_holder_disallow_demote(gh);