This patch extends /proc/<pid>/fdinfo/<fd> to report information about open
files, and pathname. This information can be useful to know when debugging an
application.
For each file descriptor, the information is provided in the following format:
kerndev: ~/code/kernel# cat /proc/`pgrep pickup`/fdinfo/6
mode: 0622
dev: 253,0
ino: 21463057
uid: 89
gid: 89
rdev: 0,0
pos: 0
flags: 04002 FD_CLOEXEC # if close-on-exec flag is set
path: /var/spool/postfix/public/pickup
You can also use this to find out more information about locked open files:
kerndev: /proc# cat /proc/locks
1: POSIX ADVISORY WRITE 2663 fd:00:21398205 0 EOF
^^^^ ^^^^^^^^
2: FLOCK ADVISORY WRITE 2654 fd:00:21398203 0 EOF
3: FLOCK ADVISORY WRITE 2564 fd:00:21463056 0 EOF
4: FLOCK ADVISORY WRITE 2266 fd:00:21398151 0 EOF
kerndev: /proc# cd 2663/fdinfo/
kerndev: /proc/2663/fdinfo# grep 21398205 * -B2 -A6
^^^^
3-mode: 0644
3-dev: 253,0
3:ino: 21398205
^^^^^^^^
3-uid: 0
3-gid: 0
3-rdev: 0,0
3-pos: 5
3-flags: 02 FD_CLOEXEC
3-path: /var/run/atd.pid
Signed-off-by: Eugene Teo <[EMAIL PROTECTED]>
---
fs/proc/base.c | 47 +++++++++++++++++++++++++++++++++++++++++------
1 files changed, 41 insertions(+), 6 deletions(-)
diff --git a/fs/proc/base.c b/fs/proc/base.c
index c59852b..dde617f 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -1402,7 +1402,7 @@ out:
return ~0U;
}
-#define PROC_FDINFO_MAX 64
+#define PROC_FDINFO_MAX 256
static int proc_fd_info(struct inode *inode, struct dentry **dentry,
struct vfsmount **mnt, char *info)
@@ -1411,6 +1411,7 @@ static int proc_fd_info(struct inode *inode, struct
dentry **dentry,
struct files_struct *files = NULL;
struct file *file;
int fd = proc_fd(inode);
+ int ret = -ENOENT;
if (task) {
files = get_files_struct(task);
@@ -1424,24 +1425,58 @@ static int proc_fd_info(struct inode *inode, struct
dentry **dentry,
spin_lock(&files->file_lock);
file = fcheck_files(files, fd);
if (file) {
+ ret = 0;
+
if (mnt)
*mnt = mntget(file->f_path.mnt);
if (dentry)
*dentry = dget(file->f_path.dentry);
- if (info)
+ /* called by proc_fdinfo_read() */
+ if (info) {
+ struct fdtable *fdt = files_fdtable(files);
+ struct dentry *d = dget(file->f_path.dentry);
+ struct vfsmount *v = mntget(file->f_path.mnt);
+ char *page = (char
*)__get_free_page(GFP_TEMPORARY);
+ int gcoe = FD_ISSET(fd, fdt->close_on_exec);
+ int dev_nr = d->d_inode->i_sb->s_dev;
+ int rdev_nr = d->d_inode->i_rdev;
+
+ if (!page) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
snprintf(info, PROC_FDINFO_MAX,
+ "mode:\t0%o\n"
+ "dev:\t%d,%d\n"
+ "ino:\t%ld\n"
+ "uid:\t%d\n"
+ "gid:\t%d\n"
+ "rdev:\t%d,%d\n"
"pos:\t%lli\n"
- "flags:\t0%o\n",
+ "flags:\t0%o %s\n"
+ "path:\t%s\n",
+ d->d_inode->i_mode & 0777,
+ MAJOR(dev_nr), MINOR(dev_nr),
+ d->d_inode->i_ino,
+ file->f_uid, file->f_gid,
+ MAJOR(rdev_nr), MINOR(rdev_nr),
(long long) file->f_pos,
- file->f_flags);
+ file->f_flags, gcoe ? "FD_CLOEXEC" :
"",
+ d_path(d, v, page, PAGE_SIZE));
+ free_page((unsigned long)page);
+out:
+ mntput(v);
+ dput(d);
+ }
spin_unlock(&files->file_lock);
put_files_struct(files);
- return 0;
+ return ret;
}
spin_unlock(&files->file_lock);
put_files_struct(files);
}
- return -ENOENT;
+ return ret;
}
static int proc_fd_link(struct inode *inode, struct dentry **dentry,
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
