JieJing.Zhang
2010-Jun-19 18:13 UTC
[PATCH] Btrfs: handle kmalloc() failure in btrfs_file_aio_write()
set errno to -ENOMEM and goto out
Signed-off-by: JieJing.Zhang <kzjeef@gmail.com>
---
fs/btrfs/file.c | 4 ++++
1 files changed, 4 insertions(+), 0 deletions(-)
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index e354c33..e0fcb6c 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -926,6 +926,10 @@ static ssize_t btrfs_file_aio_write(struct kiocb *iocb,
PAGE_CACHE_SIZE, PAGE_CACHE_SIZE /
(sizeof(struct page *)));
pages = kmalloc(nrptrs * sizeof(struct page *), GFP_KERNEL);
+ if (!pages) {
+ ret = -ENOMEM;
+ goto out;
+ }
/* generic_write_checks can change our pos */
start_pos = pos;
--
1.7.0.4
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs"
in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Zhang JieJing
2010-Jun-20 04:56 UTC
Re: [PATCH] Btrfs: handle kmalloc() failure in btrfs_file_aio_write()
2010/6/20 JieJing.Zhang <kzjeef@gmail.com>> > set errno to -ENOMEM and goto out > > Signed-off-by: JieJing.Zhang <kzjeef@gmail.com> > --- > fs/btrfs/file.c | 4 ++++ > 1 files changed, 4 insertions(+), 0 deletions(-) > > diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c > index e354c33..e0fcb6c 100644 > --- a/fs/btrfs/file.c > +++ b/fs/btrfs/file.c > @@ -926,6 +926,10 @@ static ssize_t btrfs_file_aio_write(struct kiocb *iocb, > PAGE_CACHE_SIZE, PAGE_CACHE_SIZE / > (sizeof(struct page *))); > pages = kmalloc(nrptrs * sizeof(struct page *), GFP_KERNEL);I think this gfp should changed to GFP_NOFS to avoid deadlock, right ? like this commit: 33818bbb84cd371b63ed8849cc5264d24c8b3aa2> + if (!pages) { > + ret = -ENOMEM; > + goto out; > + } > > /* generic_write_checks can change our pos */ > start_pos = pos; > -- > 1.7.0.4 >-- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Zhang JieJing
2010-Jul-03 17:35 UTC
Re: [PATCH] Btrfs: handle kmalloc() failure in btrfs_file_aio_write()
This is the improved of the former patch.
From d9c4cf7dd0e4489a31610e2fb2565ee29f0e4179 Mon Sep 17 00:00:00 2001
From: JieJing.Zhang <kzjeef@gmail.com>
Date: Sun, 4 Jul 2010 01:17:54 +0800
Subject: [PATCH] Btrfs: handle memory alloc failure in btrfs_file_aio_write()
1. kmalloc() should add a check of return valule.
2. In later code it memset zero to the allocated memory,
so use kzalloc() instead of kmalloc() when allocation is better.
Signed-off-by: JieJing.Zhang <kzjeef@gmail.com>
---
fs/btrfs/file.c | 7 +++++--
1 files changed, 5 insertions(+), 2 deletions(-)
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index e354c33..961612c 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -925,7 +925,11 @@ static ssize_t btrfs_file_aio_write(struct kiocb *iocb,
nrptrs = min((iov_iter_count(&i) + PAGE_CACHE_SIZE - 1) /
PAGE_CACHE_SIZE, PAGE_CACHE_SIZE /
(sizeof(struct page *)));
- pages = kmalloc(nrptrs * sizeof(struct page *), GFP_KERNEL);
+ pages = kzalloc(nrptrs * sizeof(struct page *), GFP_KERNEL);
+ if (!pages) {
+ ret = -ENOMEM;
+ goto out;
+ }
/* generic_write_checks can change our pos */
start_pos = pos;
@@ -968,7 +972,6 @@ static ssize_t btrfs_file_aio_write(struct kiocb *iocb,
PAGE_CACHE_SHIFT;
WARN_ON(num_pages > nrptrs);
- memset(pages, 0, sizeof(struct page *) * nrptrs);
ret = btrfs_delalloc_reserve_space(inode, write_bytes);
if (ret)
--
1.7.0.4
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs"
in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html