linux-fsdevel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Al Viro <viro@ZenIV.linux.org.uk>
To: linux-kernel@vger.kernel.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
	Neil Brown <neilb@suse.com>,
	linux-fsdevel@vger.kernel.org
Subject: [PATCH v2 05/11] namei: page_getlink() and page_follow_link_light() are the same thing
Date: Wed,  9 Dec 2015 05:34:49 +0000	[thread overview]
Message-ID: <1449639295-20512-5-git-send-email-viro@ZenIV.linux.org.uk> (raw)
In-Reply-To: <20151209053209.GV20997@ZenIV.linux.org.uk>

From: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 fs/namei.c | 32 +++++++++++++-------------------
 1 file changed, 13 insertions(+), 19 deletions(-)

diff --git a/fs/namei.c b/fs/namei.c
index 0c3974c..4bae5cb 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -4518,7 +4518,7 @@ int generic_readlink(struct dentry *dentry, char __user *buffer, int buflen)
 EXPORT_SYMBOL(generic_readlink);
 
 /* get the link contents into pagecache */
-static char *page_getlink(struct dentry * dentry, struct page **ppage)
+static const char *page_getlink(struct dentry * dentry, void **cookie)
 {
 	char *kaddr;
 	struct page *page;
@@ -4526,31 +4526,15 @@ static char *page_getlink(struct dentry * dentry, struct page **ppage)
 	page = read_mapping_page(mapping, 0, NULL);
 	if (IS_ERR(page))
 		return (char*)page;
-	*ppage = page;
+	*cookie = page;
 	kaddr = kmap(page);
 	nd_terminate_link(kaddr, dentry->d_inode->i_size, PAGE_SIZE - 1);
 	return kaddr;
 }
 
-int page_readlink(struct dentry *dentry, char __user *buffer, int buflen)
-{
-	struct page *page = NULL;
-	int res = readlink_copy(buffer, buflen, page_getlink(dentry, &page));
-	if (page) {
-		kunmap(page);
-		page_cache_release(page);
-	}
-	return res;
-}
-EXPORT_SYMBOL(page_readlink);
-
 const char *page_follow_link_light(struct dentry *dentry, void **cookie)
 {
-	struct page *page = NULL;
-	char *res = page_getlink(dentry, &page);
-	if (!IS_ERR(res))
-		*cookie = page;
-	return res;
+	return page_getlink(dentry, cookie);
 }
 EXPORT_SYMBOL(page_follow_link_light);
 
@@ -4562,6 +4546,16 @@ void page_put_link(struct inode *unused, void *cookie)
 }
 EXPORT_SYMBOL(page_put_link);
 
+int page_readlink(struct dentry *dentry, char __user *buffer, int buflen)
+{
+	void *cookie = NULL;
+	int res = readlink_copy(buffer, buflen, page_getlink(dentry, &cookie));
+	if (cookie)
+		page_put_link(NULL, cookie);
+	return res;
+}
+EXPORT_SYMBOL(page_readlink);
+
 /*
  * The nofs argument instructs pagecache_write_begin to pass AOP_FLAG_NOFS
  */
-- 
2.1.4


  parent reply	other threads:[~2015-12-09  5:34 UTC|newest]

Thread overview: 48+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-11-17 22:57 [PATCHSET] ->follow_link() without dropping from RCU mode Al Viro
2015-11-17 23:00 ` [PATCH 01/10] switch befs long symlinks to page_symlink_operations Al Viro
2015-11-17 23:00 ` [PATCH 02/10] logfs: don't duplicate page_symlink_inode_operations Al Viro
2015-11-17 23:00 ` [PATCH 03/10] udf: " Al Viro
2015-11-17 23:00 ` [PATCH 04/10] ufs: get rid of ->setattr() for symlinks Al Viro
2015-11-17 23:00 ` [PATCH 05/10] namei: page_getlink() and page_follow_link_light() are the same thing Al Viro
2015-11-17 23:00 ` [PATCH 06/10] [vfs] don't put symlink bodies in pagecache into highmem Al Viro
2015-11-19 23:02   ` Dave Chinner
2015-11-17 23:00 ` [PATCH 07/10] [vfs] replace ->follow_link() with new method that could stay in RCU mode Al Viro
2015-11-17 23:00 ` [PATCH 08/10] teach page_get_link() to work " Al Viro
2015-11-17 23:00 ` [PATCH 09/10] teach shmem_get_link() " Al Viro
2015-11-17 23:00 ` [PATCH 10/10] teach proc_self_get_link()/proc_thread_self_get_link() " Al Viro
2015-12-09  5:32 ` [PATCHSET v2] ->follow_link() without dropping from " Al Viro
2015-12-09  5:34   ` [PATCH v2 01/11] switch befs long symlinks to page_symlink_operations Al Viro
2015-12-09  5:34   ` [PATCH v2 02/11] logfs: don't duplicate page_symlink_inode_operations Al Viro
2015-12-09  5:34   ` [PATCH v2 03/11] udf: " Al Viro
2015-12-09  5:34   ` [PATCH v2 04/11] ufs: get rid of ->setattr() for symlinks Al Viro
2015-12-09  5:34   ` Al Viro [this message]
2015-12-09  5:34   ` [PATCH v2 06/11] don't put symlink bodies in pagecache into highmem Al Viro
2016-01-14 13:22     ` Tomeu Vizoso
2016-01-14 15:25       ` Al Viro
2016-01-14 15:58         ` Tomeu Vizoso
2016-01-14 16:23           ` Al Viro
2016-01-14 16:57             ` Tomeu Vizoso
2016-01-14 17:13               ` Al Viro
2016-01-14 19:15                 ` Tomeu Vizoso
2016-01-14 21:02                   ` Al Viro
2016-01-14 21:40                     ` Linus Torvalds
2016-01-14 22:25                       ` Al Viro
2016-01-14 23:33                         ` Al Viro
2016-01-14 23:58                         ` Linus Torvalds
2016-01-15  0:05                           ` Al Viro
2015-12-09  5:34   ` [PATCH v2 07/11] replace ->follow_link() with new method that could stay in RCU mode Al Viro
2015-12-09  5:34   ` [PATCH v2 08/11] teach page_get_link() to work " Al Viro
2015-12-09  5:34   ` [PATCH v2 09/11] teach shmem_get_link() " Al Viro
2015-12-09  5:34   ` [PATCH v2 10/11] teach proc_self_get_link()/proc_thread_self_get_link() " Al Viro
2015-12-09  5:34   ` [PATCH v2 11/11] teach nfs_get_link() " Al Viro
2015-12-09 17:24   ` [PATCHSET v2] ->follow_link() without dropping from " Linus Torvalds
2015-12-09 18:23     ` Al Viro
2015-12-10  0:10       ` Al Viro
2015-12-10  2:40         ` Al Viro
2015-12-11  1:54           ` Al Viro
2015-12-11  7:49             ` Rasmus Villemoes
2015-12-11 23:16               ` Al Viro
2015-12-12  2:00                 ` Al Viro
2015-12-13 18:43                   ` Rasmus Villemoes
2015-12-13  3:47             ` Al Viro
2015-12-09 21:57   ` NeilBrown

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1449639295-20512-5-git-send-email-viro@ZenIV.linux.org.uk \
    --to=viro@zeniv.linux.org.uk \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=neilb@suse.com \
    --cc=torvalds@linux-foundation.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).