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| author | Christian Brauner <brauner@kernel.org> | 2024-10-14 16:31:22 +0200 |
|---|---|---|
| committer | Christian Brauner <brauner@kernel.org> | 2024-10-14 16:31:22 +0200 |
| commit | 58439f6c48a9dc7a12765a6b37a5c43a542ea90f (patch) | |
| tree | 7dc972388902272687e9f4ca69a6298a2d45d917 /include/linux | |
| parent | 8e929cb546ee42c9a61d24fae60605e9e3192354 (diff) | |
| parent | af9199145b1977316b3c752e2124543e320f087f (diff) | |
Merge patch series "ovl: file descriptors based layer setup"
Christian Brauner <brauner@kernel.org> says:
Currently overlayfs only allows specifying layers through path names.
This is inconvenient for users such as systemd that want to assemble an
overlayfs mount purely based on file descriptors.
When porting overlayfs to the new mount api I already mentioned this.
This enables user to specify both:
fsconfig(fd_overlay, FSCONFIG_SET_FD, "upperdir+", NULL, fd_upper);
fsconfig(fd_overlay, FSCONFIG_SET_FD, "workdir+", NULL, fd_work);
fsconfig(fd_overlay, FSCONFIG_SET_FD, "lowerdir+", NULL, fd_lower1);
fsconfig(fd_overlay, FSCONFIG_SET_FD, "lowerdir+", NULL, fd_lower2);
in addition to:
fsconfig(fd_overlay, FSCONFIG_SET_STRING, "upperdir+", "/upper", 0);
fsconfig(fd_overlay, FSCONFIG_SET_STRING, "workdir+", "/work", 0);
fsconfig(fd_overlay, FSCONFIG_SET_STRING, "lowerdir+", "/lower1", 0);
fsconfig(fd_overlay, FSCONFIG_SET_STRING, "lowerdir+", "/lower2", 0);
The selftest contain an example for this.
* patches from https://lore.kernel.org/r/20241014-work-overlayfs-v3-0-32b3fed1286e@kernel.org:
selftests: add overlayfs fd mounting selftests
selftests: use shared header
Documentation,ovl: document new file descriptor based layers
ovl: specify layers via file descriptors
fs: add helper to use mount option as path or fd
Link: https://lore.kernel.org/r/20241014-work-overlayfs-v3-0-32b3fed1286e@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/fs_parser.h | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/include/linux/fs_parser.h b/include/linux/fs_parser.h index 6cf713a7e6c6..3cef566088fc 100644 --- a/include/linux/fs_parser.h +++ b/include/linux/fs_parser.h @@ -28,7 +28,8 @@ typedef int fs_param_type(struct p_log *, */ fs_param_type fs_param_is_bool, fs_param_is_u32, fs_param_is_s32, fs_param_is_u64, fs_param_is_enum, fs_param_is_string, fs_param_is_blob, fs_param_is_blockdev, - fs_param_is_path, fs_param_is_fd, fs_param_is_uid, fs_param_is_gid; + fs_param_is_path, fs_param_is_fd, fs_param_is_uid, fs_param_is_gid, + fs_param_is_file_or_string; /* * Specification of the type of value a parameter wants. @@ -133,6 +134,8 @@ static inline bool fs_validate_description(const char *name, #define fsparam_bdev(NAME, OPT) __fsparam(fs_param_is_blockdev, NAME, OPT, 0, NULL) #define fsparam_path(NAME, OPT) __fsparam(fs_param_is_path, NAME, OPT, 0, NULL) #define fsparam_fd(NAME, OPT) __fsparam(fs_param_is_fd, NAME, OPT, 0, NULL) +#define fsparam_file_or_string(NAME, OPT) \ + __fsparam(fs_param_is_file_or_string, NAME, OPT, 0, NULL) #define fsparam_uid(NAME, OPT) __fsparam(fs_param_is_uid, NAME, OPT, 0, NULL) #define fsparam_gid(NAME, OPT) __fsparam(fs_param_is_gid, NAME, OPT, 0, NULL) |