From: David Howells <dhowells@redhat.com>
To: viro@zeniv.linux.org.uk
Cc: torvalds@linux-foundation.org, dhowells@redhat.com,
linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
mszeredi@redhat.com
Subject: [PATCH 3/5] vfs: Allow fsinfo() to query what's in an fs_context [ver #12]
Date: Fri, 21 Sep 2018 17:38:11 +0100 [thread overview]
Message-ID: <153754789135.19213.18110372705954700799.stgit@warthog.procyon.org.uk> (raw)
In-Reply-To: <153754786825.19213.16907802981157370740.stgit@warthog.procyon.org.uk>
Allow fsinfo() to be used to query the filesystem attached to an fs_context
once a superblock has been created or if it comes from fspick().
This is done with something like:
fd = fsopen("ext4", 0);
...
fsconfig(fd, fsconfig_cmd_create, ...);
fsinfo(fd, NULL, ...);
Signed-off-by: David Howells <dhowells@redhat.com>
---
fs/statfs.c | 32 ++++++++++++++++++++++++++++++--
1 file changed, 30 insertions(+), 2 deletions(-)
diff --git a/fs/statfs.c b/fs/statfs.c
index f3cf8aa42a3d..790e21367d70 100644
--- a/fs/statfs.c
+++ b/fs/statfs.c
@@ -636,7 +636,8 @@ int vfs_fsinfo(struct path *path, struct fsinfo_kparams *params)
return ret;
if (params->request == FSINFO_ATTR_IDS &&
- params->buffer) {
+ params->buffer &&
+ path->mnt) {
struct fsinfo_ids *p = params->buffer;
p->f_flags |= flags_by_mnt(path->mnt->mnt_flags);
@@ -677,13 +678,40 @@ static int vfs_fsinfo_path(int dfd, const char __user *filename,
return ret;
}
+static int vfs_fsinfo_fscontext(struct fs_context *fc,
+ struct fsinfo_kparams *params)
+{
+ int ret;
+
+ if (fc->ops == &legacy_fs_context_ops)
+ return -EOPNOTSUPP;
+
+ ret = mutex_lock_interruptible(&fc->uapi_mutex);
+ if (ret < 0)
+ return ret;
+
+ ret = -EIO;
+ if (fc->root) {
+ struct path path = { .dentry = fc->root };
+
+ ret = vfs_fsinfo(&path, params);
+ }
+
+ mutex_unlock(&fc->uapi_mutex);
+ return ret;
+}
+
static int vfs_fsinfo_fd(unsigned int fd, struct fsinfo_kparams *params)
{
struct fd f = fdget_raw(fd);
int ret = -EBADF;
if (f.file) {
- ret = vfs_fsinfo(&f.file->f_path, params);
+ if (f.file->f_op == &fscontext_fops)
+ ret = vfs_fsinfo_fscontext(f.file->private_data,
+ params);
+ else
+ ret = vfs_fsinfo(&f.file->f_path, params);
fdput(f);
}
return ret;
next prev parent reply other threads:[~2018-09-21 16:38 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-09-21 16:37 [PATCH 0/5] VFS: Introduce filesystem information query syscall [ver #12] David Howells
2018-09-21 16:37 ` [PATCH 1/5] vfs: syscall: Add fsinfo() to query filesystem information " David Howells
2018-09-21 16:38 ` [PATCH 2/5] afs: Add fsinfo support " David Howells
2018-09-21 16:38 ` David Howells [this message]
2018-09-21 16:38 ` [PATCH 4/5] vfs: Allow fsinfo() to be used to query an fs parameter description " David Howells
2018-09-21 16:38 ` [PATCH 5/5] vfs: Implement parameter value retrieval with fsinfo() " David Howells
2018-09-21 19:50 ` [PATCH 0/5] VFS: Introduce filesystem information query syscall " Rasmus Villemoes
2018-10-10 11:58 ` David Howells
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=153754789135.19213.18110372705954700799.stgit@warthog.procyon.org.uk \
--to=dhowells@redhat.com \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mszeredi@redhat.com \
--cc=torvalds@linux-foundation.org \
--cc=viro@zeniv.linux.org.uk \
/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).