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From: Dave Hansen <dave@linux.vnet.ibm.com>
To: Ingo Molnar <mingo@elte.hu>
Cc: containers <containers@lists.linux-foundation.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"Serge E. Hallyn" <serue@us.ibm.com>,
	Oren Laadan <orenl@cs.columbia.edu>,
	Alexey Dobriyan <adobriyan@gmail.com>,
	Christoph Hellwig <hch@infradead.org>,
	Dave Hansen <dave@linux.vnet.ibm.com>
Subject: [RFC][PATCH 02/11] breakout fdinfo sprintf() into its own function
Date: Thu, 05 Mar 2009 08:38:59 -0800	[thread overview]
Message-ID: <20090305163859.584741AF@kernel> (raw)
In-Reply-To: <20090305163857.0C18F3FD@kernel>


I'll be adding to this in a moment and it is in a bad place
to do that cleanly now.

Also, increase the buffer size.  Most /proc files can
output up to a page, so use the same here.

Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com>
---

 linux-2.6.git-dave/fs/proc/base.c |   23 +++++++++++++++--------
 1 file changed, 15 insertions(+), 8 deletions(-)

diff -puN fs/proc/base.c~breakout-fdinfo-sprintf fs/proc/base.c
--- linux-2.6.git/fs/proc/base.c~breakout-fdinfo-sprintf	2009-03-05 08:37:00.000000000 -0800
+++ linux-2.6.git-dave/fs/proc/base.c	2009-03-05 08:37:00.000000000 -0800
@@ -1632,7 +1632,18 @@ out:
 	return ~0U;
 }
 
-#define PROC_FDINFO_MAX 64
+#define PROC_FDINFO_MAX PAGE_SIZE
+
+static void proc_fd_write_info(struct file *file, char *info)
+{
+	int max = PROC_FDINFO_MAX;
+	int p = 0;
+	if (!info)
+		return;
+
+	p += scnprintf(info+p, max-p, "pos:\t%lli\n", (long long) file->f_pos);
+	p += scnprintf(info+p, max-p, "flags:\t0%o\n", file->f_flags);
+}
 
 static int proc_fd_info(struct inode *inode, struct path *path, char *info)
 {
@@ -1657,12 +1668,7 @@ static int proc_fd_info(struct inode *in
 				*path = file->f_path;
 				path_get(&file->f_path);
 			}
-			if (info)
-				snprintf(info, PROC_FDINFO_MAX,
-					 "pos:\t%lli\n"
-					 "flags:\t0%o\n",
-					 (long long) file->f_pos,
-					 file->f_flags);
+			proc_fd_write_info(file, info);
 			spin_unlock(&files->file_lock);
 			put_files_struct(files);
 			return 0;
@@ -1870,10 +1876,11 @@ static int proc_readfd(struct file *filp
 static ssize_t proc_fdinfo_read(struct file *file, char __user *buf,
 				      size_t len, loff_t *ppos)
 {
-	char tmp[PROC_FDINFO_MAX];
+	char *tmp = kmalloc(PROC_FDINFO_MAX, GFP_KERNEL);
 	int err = proc_fd_info(file->f_path.dentry->d_inode, NULL, tmp);
 	if (!err)
 		err = simple_read_from_buffer(buf, len, ppos, tmp, strlen(tmp));
+	kfree(tmp);
 	return err;
 }
 
_

  parent reply	other threads:[~2009-03-05 16:39 UTC|newest]

Thread overview: 47+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-03-05 16:38 [RFC][PATCH 00/11] track files for checkpointability Dave Hansen
2009-03-05 16:38 ` [RFC][PATCH 01/11] kill '_data' in cr_hdr_fd_data name Dave Hansen
2009-03-05 16:38 ` Dave Hansen [this message]
2009-03-05 16:39 ` [RFC][PATCH 03/11] Introduce generic_file_checkpoint() Dave Hansen
2009-03-05 16:39 ` [RFC][PATCH 04/11] actually use f_op in checkpoint code Dave Hansen
2009-03-05 16:39 ` [RFC][PATCH 05/11] add generic checkpoint f_op to ext fses Dave Hansen
2009-03-13  2:50   ` Oren Laadan
2009-03-05 16:39 ` [RFC][PATCH 06/11] add checkpoint_file_generic() to /proc Dave Hansen
2009-03-05 16:39 ` [RFC][PATCH 07/11] file c/r: expose functions to query fs support Dave Hansen
2009-03-05 16:39 ` [RFC][PATCH 08/11] expose file checkpointability and reasoning in /proc Dave Hansen
2009-03-05 16:39 ` [RFC][PATCH 09/11] check files for checkpointability Dave Hansen
2009-03-09 17:38   ` Matt Helsley
2009-03-12 19:14     ` Dave Hansen
2009-03-05 16:39 ` [RFC][PATCH 10/11] add checkpoint/restart compile helper Dave Hansen
2009-03-05 16:39 ` [RFC][PATCH 11/11] optimize c/r check in dup_fd() Dave Hansen
2009-03-05 17:40 ` [RFC][PATCH 00/11] track files for checkpointability Alexey Dobriyan
2009-03-05 19:16   ` Dave Hansen
2009-03-05 21:08     ` Alexey Dobriyan
2009-03-05 21:27       ` Dave Hansen
2009-03-05 22:00         ` Alexey Dobriyan
2009-03-05 22:24           ` Dave Hansen
2009-03-06 14:34             ` Serge E. Hallyn
2009-03-06 15:48               ` Dave Hansen
2009-03-06 16:23                 ` Serge E. Hallyn
2009-03-06 16:46                   ` Dave Hansen
2009-03-06 18:24                     ` Serge E. Hallyn
2009-03-06 19:42                       ` Dave Hansen
2009-03-13  3:05               ` Oren Laadan
2009-03-06 15:08           ` Greg Kurz
2009-03-06 15:35             ` Serge E. Hallyn
2009-03-06 17:36               ` Cedric Le Goater
2009-03-06 18:30                 ` Serge E. Hallyn
2009-03-11  7:51                   ` Cedric Le Goater
2009-03-12 15:30                     ` Serge E. Hallyn
2009-03-13  6:36                       ` Ensuring c/r maintainability (WAS Re: [RFC][PATCH 00/11] track files for checkpointability) Matt Helsley
2009-03-13 17:53                         ` Serge E. Hallyn
2009-03-05 19:44   ` [RFC][PATCH 00/11] track files for checkpointability Dave Hansen
2009-03-05 18:13 ` Serge E. Hallyn
2009-03-05 18:16   ` Dave Hansen
2009-03-10 15:57 ` Nathan Lynch
2009-03-10 16:00   ` Nathan Lynch
2009-03-10 16:23     ` Serge E. Hallyn
2009-03-10 16:20   ` Serge E. Hallyn
2009-03-10 17:23     ` Nathan Lynch
2009-03-10 17:45       ` Serge E. Hallyn
2009-03-10 17:47         ` Dave Hansen
2009-03-10 16:22   ` Dave Hansen

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