From: Ajay Kaher <akaher@vmware.com>
To: <gregkh@linuxfoundation.org>
Cc: <torvalds@linux-foundation.org>, <punit.agrawal@arm.com>,
<akpm@linux-foundation.org>, <kirill.shutemov@linux.intel.com>,
<willy@infradead.org>, <will.deacon@arm.com>,
<mszeredi@redhat.com>, <stable@vger.kernel.org>,
<linux-mm@kvack.org>, <linux-kernel@vger.kernel.org>,
<srivatsab@vmware.com>, <srivatsa@csail.mit.edu>,
<amakhalov@vmware.com>, <srinidhir@vmware.com>,
<bvikas@vmware.com>, <anishs@vmware.com>,
<vsirnapalli@vmware.com>, <srostedt@vmware.com>,
<akaher@vmware.com>, Al Viro <viro@zeniv.linux.org.uk>,
Vlastimil Babka <vbabka@suse.cz>
Subject: [PATCH v3 6/8] pipe: add pipe_buf_get() helper
Date: Tue, 17 Dec 2019 02:15:46 +0530 [thread overview]
Message-ID: <1576529149-14269-7-git-send-email-akaher@vmware.com> (raw)
In-Reply-To: <1576529149-14269-1-git-send-email-akaher@vmware.com>
From: Miklos Szeredi <mszeredi@redhat.com>
commit 7bf2d1df80822ec056363627e2014990f068f7aa upstream.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Ajay Kaher <akaher@vmware.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
---
fs/fuse/dev.c | 2 +-
fs/splice.c | 4 ++--
include/linux/pipe_fs_i.h | 11 +++++++++++
3 files changed, 14 insertions(+), 3 deletions(-)
diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index f5d2d23..36a5df9 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -2052,7 +2052,7 @@ static ssize_t fuse_dev_splice_write(struct pipe_inode_info *pipe,
pipe->curbuf = (pipe->curbuf + 1) & (pipe->buffers - 1);
pipe->nrbufs--;
} else {
- ibuf->ops->get(pipe, ibuf);
+ pipe_buf_get(pipe, ibuf);
*obuf = *ibuf;
obuf->flags &= ~PIPE_BUF_FLAG_GIFT;
obuf->len = rem;
diff --git a/fs/splice.c b/fs/splice.c
index 8398974..fde1263 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -1876,7 +1876,7 @@ retry:
* Get a reference to this pipe buffer,
* so we can copy the contents over.
*/
- ibuf->ops->get(ipipe, ibuf);
+ pipe_buf_get(ipipe, ibuf);
*obuf = *ibuf;
/*
@@ -1948,7 +1948,7 @@ static int link_pipe(struct pipe_inode_info *ipipe,
* Get a reference to this pipe buffer,
* so we can copy the contents over.
*/
- ibuf->ops->get(ipipe, ibuf);
+ pipe_buf_get(ipipe, ibuf);
obuf = opipe->bufs + nbuf;
*obuf = *ibuf;
diff --git a/include/linux/pipe_fs_i.h b/include/linux/pipe_fs_i.h
index 24f5470..10876f3 100644
--- a/include/linux/pipe_fs_i.h
+++ b/include/linux/pipe_fs_i.h
@@ -115,6 +115,17 @@ struct pipe_buf_operations {
void (*get)(struct pipe_inode_info *, struct pipe_buffer *);
};
+/**
+ * pipe_buf_get - get a reference to a pipe_buffer
+ * @pipe: the pipe that the buffer belongs to
+ * @buf: the buffer to get a reference to
+ */
+static inline void pipe_buf_get(struct pipe_inode_info *pipe,
+ struct pipe_buffer *buf)
+{
+ buf->ops->get(pipe, buf);
+}
+
/* Differs from PIPE_BUF in that PIPE_SIZE is the length of the actual
memory allocation, whereas PIPE_BUF makes atomicity guarantees. */
#define PIPE_SIZE PAGE_SIZE
--
2.7.4
next prev parent reply other threads:[~2019-12-16 13:01 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-12-16 20:45 [PATCH v3 0/8] Backported fixes for 4.4 stable tree Ajay Kaher
2019-12-16 20:45 ` [PATCH v3 1/8] mm: make page ref count overflow check tighter and more explicit Ajay Kaher
2019-12-16 20:45 ` [PATCH v3 2/8] mm: add 'try_get_page()' helper function Ajay Kaher
2019-12-16 20:45 ` [PATCH v3 3/8] mm, gup: remove broken VM_BUG_ON_PAGE compound check for hugepages Ajay Kaher
2019-12-16 20:45 ` [PATCH v3 4/8] mm, gup: ensure real head page is ref-counted when using hugepages Ajay Kaher
2019-12-16 20:45 ` [PATCH v3 5/8] mm: prevent get_user_pages() from overflowing page refcount Ajay Kaher
2019-12-16 20:45 ` Ajay Kaher [this message]
2019-12-16 20:45 ` [PATCH v3 7/8] fs: prevent page refcount overflow in pipe_buf_get Ajay Kaher
2019-12-16 20:45 ` [PATCH v3 8/8] x86, mm, gup: prevent get_page() race with munmap in paravirt guest Ajay Kaher
2019-12-16 13:04 ` Peter Zijlstra
2019-12-16 13:30 ` Vitaly Kuznetsov
2019-12-16 13:47 ` Peter Zijlstra
2019-12-16 15:11 ` Vlastimil Babka
2019-12-16 16:08 ` Vitaly Kuznetsov
2019-12-17 4:13 ` Ajay Kaher
2020-01-31 12:51 ` Ajay Kaher
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