From 2a82bb02941fb53d1f8df2a360e7798ae3d9d962 Mon Sep 17 00:00:00 2001
From: Kent Overstreet <kent.overstreet@linux.dev>
Date: Thu, 7 Mar 2024 21:29:12 -0500
Subject: [PATCH] statx: stx_subvol
Add a new statx field for (sub)volume identifiers, as implemented by
btrfs and bcachefs.
This includes bcachefs support; we'll definitely want btrfs support as
well.
Link: https://lore.kernel.org/linux-fsdevel/2uvhm6gweyl7iyyp2xpfryvcu2g3padagaeqcbiavjyiis6prl@yjm725bizncq/
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Link: https://lore.kernel.org/r/20240308022914.196982-1-kent.overstreet@linux.dev
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
---
fs/bcachefs/fs.c | 3 +++
fs/btrfs/inode.c | 3 +++
fs/stat.c | 1 +
include/linux/stat.h | 1 +
include/uapi/linux/stat.h | 4 +++-
5 files changed, 11 insertions(+), 1 deletion(-)
diff --git a/fs/bcachefs/fs.c b/fs/bcachefs/fs.c
index 0ccee05f6887..99a0abeadbe2 100644
--- a/fs/bcachefs/fs.c
+++ b/fs/bcachefs/fs.c
@@ -841,6 +841,9 @@ static int bch2_getattr(struct mnt_idmap *idmap,
stat->blksize = block_bytes(c);
stat->blocks = inode->v.i_blocks;
+ stat->subvol = inode->ei_subvol;
+ stat->result_mask |= STATX_SUBVOL;
+
if (request_mask & STATX_BTIME) {
stat->result_mask |= STATX_BTIME;
stat->btime = bch2_time_to_timespec(c, inode->ei_inode.bi_otime);
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 37701531eeb1..8cf692c708d7 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -8779,6 +8779,9 @@ static int btrfs_getattr(struct mnt_idmap *idmap,
generic_fillattr(idmap, request_mask, inode, stat);
stat->dev = BTRFS_I(inode)->root->anon_dev;
+ stat->subvol = BTRFS_I(inode)->root->root_key.objectid;
+ stat->result_mask |= STATX_SUBVOL;
+
spin_lock(&BTRFS_I(inode)->lock);
delalloc_bytes = BTRFS_I(inode)->new_delalloc_bytes;
inode_bytes = inode_get_bytes(inode);
diff --git a/fs/stat.c b/fs/stat.c
index 77cdc69eb422..70bd3e888cfa 100644
--- a/fs/stat.c
+++ b/fs/stat.c
@@ -658,6 +658,7 @@ cp_statx(const struct kstat *stat, struct statx __user *buffer)
tmp.stx_mnt_id = stat->mnt_id;
tmp.stx_dio_mem_align = stat->dio_mem_align;
tmp.stx_dio_offset_align = stat->dio_offset_align;
+ tmp.stx_subvol = stat->subvol;
return copy_to_user(buffer, &tmp, sizeof(tmp)) ? -EFAULT : 0;
}
diff --git a/include/linux/stat.h b/include/linux/stat.h
index 52150570d37a..bf92441dbad2 100644
--- a/include/linux/stat.h
+++ b/include/linux/stat.h
@@ -53,6 +53,7 @@ struct kstat {
u32 dio_mem_align;
u32 dio_offset_align;
u64 change_cookie;
+ u64 subvol;
};
/* These definitions are internal to the kernel for now. Mainly used by nfsd. */
diff --git a/include/uapi/linux/stat.h b/include/uapi/linux/stat.h
index 2f2ee82d5517..67626d535316 100644
--- a/include/uapi/linux/stat.h
+++ b/include/uapi/linux/stat.h
@@ -126,8 +126,9 @@ struct statx {
__u64 stx_mnt_id;
__u32 stx_dio_mem_align; /* Memory buffer alignment for direct I/O */
__u32 stx_dio_offset_align; /* File offset alignment for direct I/O */
+ __u64 stx_subvol; /* Subvolume identifier */
/* 0xa0 */
- __u64 __spare3[12]; /* Spare space for future expansion */
+ __u64 __spare3[11]; /* Spare space for future expansion */
/* 0x100 */
};
@@ -155,6 +156,7 @@ struct statx {
#define STATX_MNT_ID 0x00001000U /* Got stx_mnt_id */
#define STATX_DIOALIGN 0x00002000U /* Want/got direct I/O alignment info */
#define STATX_MNT_ID_UNIQUE 0x00004000U /* Want/got extended stx_mount_id */
+#define STATX_SUBVOL 0x00008000U /* Want/got stx_subvol */
#define STATX__RESERVED 0x80000000U /* Reserved for future struct statx expansion */
--
2.42.0