open_tree(dfd, pathname, flags) Returns an O_PATH-opened file descriptor or an error. dfd and pathname specify the location to open, in usual fashion (see e.g. fstatat(2)). flags should be an OR of some of the following: * AT_PATH_EMPTY, AT_NO_AUTOMOUNT, AT_SYMLINK_NOFOLLOW - same meanings as usual * OPEN_TREE_CLOEXEC - make the resulting descriptor close-on-exec * OPEN_TREE_CLONE or OPEN_TREE_CLONE | AT_RECURSIVE - instead of opening the location in question, create a detached mount tree matching the subtree rooted at location specified by dfd/pathname. With AT_RECURSIVE the entire subtree is cloned, without it - only the part within in the mount containing the location in question. In other words, the same as mount --rbind or mount --bind would've taken. The detached tree will be dissolved on the final close of obtained file. Creation of such detached trees requires the same capabilities as doing mount --bind.
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| @@ -91,5 +91,7 @@ · 90 unmodified lines | ||
| 91 | 91 | #define AT_STATX_FORCE_SYNC 0x2000 /* - Force the attributes to be sync'd with the server */ |
| 92 | 92 | #define AT_STATX_DONT_SYNC 0x4000 /* - Don't sync attributes with the server */ |
| 93 | 93 | |
| 94 | +#define AT_RECURSIVE 0x8000 /* Apply to the entire subtree */ | |
| 95 | + | |
| 94 | 96 | |
| 95 | 97 | #endif /* _UAPI_LINUX_FCNTL_H */ |
| @@ -55,4 +55,10 @@ · 54 unmodified lines | ||
| 55 | 55 | #define MS_MGC_VAL 0xC0ED0000 |
| 56 | 56 | #define MS_MGC_MSK 0xffff0000 |
| 57 | 57 | |
| 58 | +/* | |
| 59 | + * open_tree() flags. | |
| 60 | + */ | |
| 61 | +#define OPEN_TREE_CLONE 1 /* Clone the target tree and attach the clone */ | |
| 62 | +#define OPEN_TREE_CLOEXEC O_CLOEXEC /* Close the file on execve() */ | |
| 63 | + | |
| 58 | 64 | #endif /* _UAPI_LINUX_MOUNT_H */ |