diff mbox

[RFC,1/2] ceph: introduce 'ceph.all' virtual xattr

Message ID 1469083758-2153-1-git-send-email-vshankar@redhat.com (mailing list archive)
State New, archived
Headers show

Commit Message

Venky Shankar July 21, 2016, 6:49 a.m. UTC
As of now listing extended attributes result in ceph dump all of
it's internal xattrs thereby confusing tools such as rsync and the
likes. This functionality would be removed in the subsequent patch,
but there needs to be a way to examine ceph's internal xattr.

Remembering all internal xattrs is cumbersome and error prone, so,
we provide a virtual xattr to fetch a list of ceph's internal xattr,
obviously excluding itself.

Signed-off-by: Venky Shankar <vshankar@redhat.com>
---
 fs/ceph/xattr.c | 54 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 54 insertions(+)

Comments

Yan, Zheng July 21, 2016, 7:30 a.m. UTC | #1
On Thu, Jul 21, 2016 at 2:49 PM, Venky Shankar <vshankar@redhat.com> wrote:
> As of now listing extended attributes result in ceph dump all of
> it's internal xattrs thereby confusing tools such as rsync and the
> likes. This functionality would be removed in the subsequent patch,
> but there needs to be a way to examine ceph's internal xattr.
>
> Remembering all internal xattrs is cumbersome and error prone, so,
> we provide a virtual xattr to fetch a list of ceph's internal xattr,
> obviously excluding itself.
>
> Signed-off-by: Venky Shankar <vshankar@redhat.com>
> ---
>  fs/ceph/xattr.c | 54 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 54 insertions(+)
>
> diff --git a/fs/ceph/xattr.c b/fs/ceph/xattr.c
> index 4870b29..d0f59cb 100644
> --- a/fs/ceph/xattr.c
> +++ b/fs/ceph/xattr.c
> @@ -204,7 +204,45 @@ static size_t ceph_vxattrcb_dir_rctime(struct ceph_inode_info *ci, char *val,
>                         (long)ci->i_rctime.tv_nsec);
>  }
>
> +static struct ceph_vxattr *ceph_inode_vxattrs(struct inode *inode);
> +static size_t ceph_vxattrs_name_size(struct ceph_vxattr *vxattrs);
>
> +/* list all ceph internal xattrs */
> +static size_t ceph_vxattrcb_list_all(struct ceph_inode_info *ci, char *val,
> +                                     size_t size)
> +{
> +        struct inode *inode = &ci->vfs_inode;
> +        struct ceph_vxattr *vxattr;
> +        struct ceph_vxattr *vxattrs = ceph_inode_vxattrs(inode);
> +        u32 len, namelen;
> +        int err = 0;
> +
> +        if (!vxattrs)
> +                goto out;
> +
> +        namelen = ceph_vxattrs_name_size(vxattrs);
> +
> +        err = -ERANGE;
> +        if (size && (namelen > size))
> +                goto out;
> +        err = namelen;
> +        if (size == 0)
> +                goto out;
> +
> +        /* fill up buffer with virtual xattrs */
> +        for (err = 0, vxattr = vxattrs; vxattr->name; vxattr++) {
> +                if (!vxattr->hidden && !(vxattr->exists_cb
> +                                         && !vxattr->exists_cb(ci))) {
> +                        len = snprintf(val + err, size - err, "%s", vxattr->name);
> +                        err += len + 1;
> +                }
> +        }
> +
> + out:
> +        return err;
> +}
> +
> +#define CEPH_XATTR_LIST_INTERNAL  XATTR_CEPH_PREFIX"all"

I prefer name ceph.list

>  #define CEPH_XATTR_NAME(_type, _name)  XATTR_CEPH_PREFIX #_type "." #_name
>  #define CEPH_XATTR_NAME2(_type, _name, _name2) \
>         XATTR_CEPH_PREFIX #_type "." #_name "." #_name2
> @@ -237,6 +275,14 @@ static struct ceph_vxattr ceph_dir_vxattrs[] = {
>                 .hidden = true,
>                 .exists_cb = ceph_vxattrcb_layout_exists,
>         },
> +        {
> +                .name = CEPH_XATTR_LIST_INTERNAL,
> +                .name_size = sizeof(CEPH_XATTR_LIST_INTERNAL),
> +                .getxattr_cb = ceph_vxattrcb_list_all,
> +                .readonly = true,
> +                .hidden = true,
> +                .exists_cb = NULL,
> +        },
>         XATTR_LAYOUT_FIELD(dir, layout, stripe_unit),
>         XATTR_LAYOUT_FIELD(dir, layout, stripe_count),
>         XATTR_LAYOUT_FIELD(dir, layout, object_size),
> @@ -264,6 +310,14 @@ static struct ceph_vxattr ceph_file_vxattrs[] = {
>                 .hidden = true,
>                 .exists_cb = ceph_vxattrcb_layout_exists,
>         },
> +        {
> +                .name = CEPH_XATTR_LIST_INTERNAL,
> +                .name_size = sizeof(CEPH_XATTR_LIST_INTERNAL),
> +                .getxattr_cb = ceph_vxattrcb_list_all,
> +                .readonly = true,
> +                .hidden = true,
> +                .exists_cb = NULL,
> +        },
>         XATTR_LAYOUT_FIELD(file, layout, stripe_unit),
>         XATTR_LAYOUT_FIELD(file, layout, stripe_count),
>         XATTR_LAYOUT_FIELD(file, layout, object_size),


Need to change the 'hidden' attribute of all other vxattrs to false.

Regards
Yan, Zheng


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Venky Shankar July 21, 2016, 12:17 p.m. UTC | #2
v2: vxattrs 'hidden' attribute defaults to false

Venky Shankar (2):
  ceph: introduce 'ceph.all' virtual xattr
  ceph: do not return virtual xattrs in listxattr()

 fs/ceph/xattr.c | 83 +++++++++++++++++++++++++++++++++++++++------------------
 1 file changed, 57 insertions(+), 26 deletions(-)
Christoph Hellwig July 22, 2016, 4:41 a.m. UTC | #3
On Thu, Jul 21, 2016 at 05:47:28PM +0530, Venky Shankar wrote:
> v2: vxattrs 'hidden' attribute defaults to false
> 
> Venky Shankar (2):
>   ceph: introduce 'ceph.all' virtual xattr
>   ceph: do not return virtual xattrs in listxattr()

NAK.  No new magic namespaces outside the documented systems ones,
please.  And especially no 'magic' attributes in 'magic' namespaces.

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diff mbox

Patch

diff --git a/fs/ceph/xattr.c b/fs/ceph/xattr.c
index 4870b29..d0f59cb 100644
--- a/fs/ceph/xattr.c
+++ b/fs/ceph/xattr.c
@@ -204,7 +204,45 @@  static size_t ceph_vxattrcb_dir_rctime(struct ceph_inode_info *ci, char *val,
 			(long)ci->i_rctime.tv_nsec);
 }
 
+static struct ceph_vxattr *ceph_inode_vxattrs(struct inode *inode);
+static size_t ceph_vxattrs_name_size(struct ceph_vxattr *vxattrs);
 
+/* list all ceph internal xattrs */
+static size_t ceph_vxattrcb_list_all(struct ceph_inode_info *ci, char *val,
+                                     size_t size)
+{
+        struct inode *inode = &ci->vfs_inode;
+        struct ceph_vxattr *vxattr;
+        struct ceph_vxattr *vxattrs = ceph_inode_vxattrs(inode);
+        u32 len, namelen;
+        int err = 0;
+
+        if (!vxattrs)
+                goto out;
+
+        namelen = ceph_vxattrs_name_size(vxattrs);
+
+        err = -ERANGE;
+        if (size && (namelen > size))
+                goto out;
+        err = namelen;
+        if (size == 0)
+                goto out;
+
+        /* fill up buffer with virtual xattrs */
+        for (err = 0, vxattr = vxattrs; vxattr->name; vxattr++) {
+                if (!vxattr->hidden && !(vxattr->exists_cb
+                                         && !vxattr->exists_cb(ci))) {
+                        len = snprintf(val + err, size - err, "%s", vxattr->name);
+                        err += len + 1;
+                }
+        }
+
+ out:
+        return err;
+}
+
+#define CEPH_XATTR_LIST_INTERNAL  XATTR_CEPH_PREFIX"all"
 #define CEPH_XATTR_NAME(_type, _name)	XATTR_CEPH_PREFIX #_type "." #_name
 #define CEPH_XATTR_NAME2(_type, _name, _name2)	\
 	XATTR_CEPH_PREFIX #_type "." #_name "." #_name2
@@ -237,6 +275,14 @@  static struct ceph_vxattr ceph_dir_vxattrs[] = {
 		.hidden = true,
 		.exists_cb = ceph_vxattrcb_layout_exists,
 	},
+        {
+                .name = CEPH_XATTR_LIST_INTERNAL,
+                .name_size = sizeof(CEPH_XATTR_LIST_INTERNAL),
+                .getxattr_cb = ceph_vxattrcb_list_all,
+                .readonly = true,
+                .hidden = true,
+                .exists_cb = NULL,
+        },
 	XATTR_LAYOUT_FIELD(dir, layout, stripe_unit),
 	XATTR_LAYOUT_FIELD(dir, layout, stripe_count),
 	XATTR_LAYOUT_FIELD(dir, layout, object_size),
@@ -264,6 +310,14 @@  static struct ceph_vxattr ceph_file_vxattrs[] = {
 		.hidden = true,
 		.exists_cb = ceph_vxattrcb_layout_exists,
 	},
+        {
+                .name = CEPH_XATTR_LIST_INTERNAL,
+                .name_size = sizeof(CEPH_XATTR_LIST_INTERNAL),
+                .getxattr_cb = ceph_vxattrcb_list_all,
+                .readonly = true,
+                .hidden = true,
+                .exists_cb = NULL,
+        },
 	XATTR_LAYOUT_FIELD(file, layout, stripe_unit),
 	XATTR_LAYOUT_FIELD(file, layout, stripe_count),
 	XATTR_LAYOUT_FIELD(file, layout, object_size),