statx: add mount ID

Systemd is hacking around to get it and it's trivial to add to statx, so...

Cc: linux-api@vger.kernel.org
Cc: linux-man@vger.kernel.org
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
This commit is contained in:
Miklos Szeredi 2020-05-14 16:44:24 +02:00
parent 761e28fa27
commit fa2fcf4f1d
3 changed files with 10 additions and 1 deletions

View File

@ -22,6 +22,7 @@
#include <asm/unistd.h>
#include "internal.h"
#include "mount.h"
/**
* generic_fillattr - Fill in the basic attributes from the inode struct
@ -199,6 +200,8 @@ int vfs_statx(int dfd, const char __user *filename, int flags,
goto out;
error = vfs_getattr(&path, stat, request_mask, flags);
stat->mnt_id = real_mount(path.mnt)->mnt_id;
stat->result_mask |= STATX_MNT_ID;
path_put(&path);
if (retry_estale(error, lookup_flags)) {
lookup_flags |= LOOKUP_REVAL;
@ -563,6 +566,7 @@ cp_statx(const struct kstat *stat, struct statx __user *buffer)
tmp.stx_rdev_minor = MINOR(stat->rdev);
tmp.stx_dev_major = MAJOR(stat->dev);
tmp.stx_dev_minor = MINOR(stat->dev);
tmp.stx_mnt_id = stat->mnt_id;
return copy_to_user(buffer, &tmp, sizeof(tmp)) ? -EFAULT : 0;
}

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@ -47,6 +47,7 @@ struct kstat {
struct timespec64 ctime;
struct timespec64 btime; /* File creation time */
u64 blocks;
u64 mnt_id;
};
#endif

View File

@ -123,7 +123,10 @@ struct statx {
__u32 stx_dev_major; /* ID of device containing file [uncond] */
__u32 stx_dev_minor;
/* 0x90 */
__u64 __spare2[14]; /* Spare space for future expansion */
__u64 stx_mnt_id;
__u64 __spare2;
/* 0xa0 */
__u64 __spare3[12]; /* Spare space for future expansion */
/* 0x100 */
};
@ -148,6 +151,7 @@ struct statx {
#define STATX_BLOCKS 0x00000400U /* Want/got stx_blocks */
#define STATX_BASIC_STATS 0x000007ffU /* The stuff in the normal stat struct */
#define STATX_BTIME 0x00000800U /* Want/got stx_btime */
#define STATX_MNT_ID 0x00001000U /* Got stx_mnt_id */
#define STATX__RESERVED 0x80000000U /* Reserved for future struct statx expansion */