From 72382264502d9348ead372f82ecc3044de5c82d2 Mon Sep 17 00:00:00 2001
From: Andreas Gruenbacher <agruenba@redhat.com>
Date: Thu, 5 May 2022 12:53:26 +0200
Subject: [PATCH] gfs2: Pull return value test out of should_fault_in_pages
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 | 34 ++++++++++++++++++++++------------
1 file changed, 22 insertions(+), 12 deletions(-)
diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c
index acc0c1d41564..ea87bef7314d 100644
--- a/fs/gfs2/file.c
+++ b/fs/gfs2/file.c
@@ -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);