When expanding ioctl interfaces we want to make sure we're not changing
the size of the structures, otherwise it can lead to incorrect transfers
between kernel and user-space.
Build time assert the size of each structure so we're not running into any
incompatibilities.
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@xxxxxxx>
---
Changes to v1:
- Stub out static_assert() for user-space (0day Bot)
- Sync asserts with the ones from btrfs-progs (David)
---
include/uapi/linux/btrfs.h | 36 ++++++++++++++++++++++++++++++++++--
1 file changed, 34 insertions(+), 2 deletions(-)
diff --git a/include/uapi/linux/btrfs.h b/include/uapi/linux/btrfs.h
index 69b88f6cb57f..dc7205972f1c 100644
--- a/include/uapi/linux/btrfs.h
+++ b/include/uapi/linux/btrfs.h
@@ -22,6 +22,10 @@
#include <linux/types.h>
#include <linux/ioctl.h>
+#ifndef static_assert
+#define static_assert(x)
+#endif
+
#define BTRFS_IOCTL_MAGIC 0x94
#define BTRFS_VOL_NAME_MAX 255
#define BTRFS_LABEL_SIZE 256
@@ -32,6 +36,7 @@ struct btrfs_ioctl_vol_args {
__s64 fd;
char name[BTRFS_PATH_NAME_MAX + 1];
};
+static_assert(sizeof(struct btrfs_ioctl_vol_args) == 4096);
#define BTRFS_DEVICE_PATH_NAME_MAX 1024
#define BTRFS_SUBVOL_NAME_MAX 4039
@@ -78,6 +83,7 @@ struct btrfs_qgroup_limit {
__u64 rsv_rfer;
__u64 rsv_excl;
};
+static_assert(sizeof(struct btrfs_qgroup_limit) == 40);
/*
* flags definition for qgroup inheritance
@@ -95,11 +101,13 @@ struct btrfs_qgroup_inherit {
struct btrfs_qgroup_limit lim;
__u64 qgroups[0];
};
+static_assert(sizeof(struct btrfs_qgroup_inherit) == 72);
struct btrfs_ioctl_qgroup_limit_args {
__u64 qgroupid;
struct btrfs_qgroup_limit lim;
};
+static_assert(sizeof(struct btrfs_ioctl_qgroup_limit_args) == 48);
/*
* Arguments for specification of subvolumes or devices, supporting by-name or
@@ -142,6 +150,7 @@ struct btrfs_ioctl_vol_args_v2 {
__u64 subvolid;
};
};
+static_assert(sizeof(struct btrfs_ioctl_vol_args_v2) == 4096);
/*
* structure to report errors and progress to userspace, either as a
@@ -190,6 +199,7 @@ struct btrfs_ioctl_scrub_args {
/* pad to 1k */
__u64 unused[(1024-32-sizeof(struct btrfs_scrub_progress))/8];
};
+static_assert(sizeof(struct btrfs_ioctl_scrub_args) == 1024);
#define BTRFS_IOCTL_DEV_REPLACE_CONT_READING_FROM_SRCDEV_MODE_ALWAYS 0
#define BTRFS_IOCTL_DEV_REPLACE_CONT_READING_FROM_SRCDEV_MODE_AVOID 1
@@ -200,6 +210,7 @@ struct btrfs_ioctl_dev_replace_start_params {
__u8 srcdev_name[BTRFS_DEVICE_PATH_NAME_MAX + 1]; /* in */
__u8 tgtdev_name[BTRFS_DEVICE_PATH_NAME_MAX + 1]; /* in */
};
+static_assert(sizeof(struct btrfs_ioctl_dev_replace_start_params) == 2072);
#define BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED 0
#define BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED 1
@@ -214,6 +225,7 @@ struct btrfs_ioctl_dev_replace_status_params {
__u64 num_write_errors; /* out */
__u64 num_uncorrectable_read_errors; /* out */
};
+static_assert(sizeof(struct btrfs_ioctl_dev_replace_status_params) == 48);
#define BTRFS_IOCTL_DEV_REPLACE_CMD_START 0
#define BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS 1
@@ -233,6 +245,7 @@ struct btrfs_ioctl_dev_replace_args {
__u64 spare[64];
};
+static_assert(sizeof(struct btrfs_ioctl_dev_replace_args) == 2600);
struct btrfs_ioctl_dev_info_args {
__u64 devid; /* in/out */
@@ -242,6 +255,7 @@ struct btrfs_ioctl_dev_info_args {
__u64 unused[379]; /* pad to 4k */
__u8 path[BTRFS_DEVICE_PATH_NAME_MAX]; /* out */
};
+static_assert(sizeof(struct btrfs_ioctl_dev_info_args) == 4096);
/*
* Retrieve information about the filesystem
@@ -270,7 +284,7 @@ struct btrfs_ioctl_fs_info_args {
__u8 metadata_uuid[BTRFS_FSID_SIZE]; /* out */
__u8 reserved[944]; /* pad to 1k */
};
-
+static_assert(sizeof(struct btrfs_ioctl_fs_info_args) == 1024);
/*
* feature flags
@@ -314,6 +328,7 @@ struct btrfs_ioctl_feature_flags {
__u64 compat_ro_flags;
__u64 incompat_flags;
};
+static_assert(sizeof(struct btrfs_ioctl_feature_flags) == 24);
/* balance control ioctl modes */
#define BTRFS_BALANCE_CTL_PAUSE 1
@@ -453,6 +468,7 @@ struct btrfs_ioctl_balance_args {
__u64 unused[72]; /* pad to 1k */
};
+static_assert(sizeof(struct btrfs_ioctl_balance_args) == 1024);
#define BTRFS_INO_LOOKUP_PATH_MAX 4080
struct btrfs_ioctl_ino_lookup_args {
@@ -460,6 +476,7 @@ struct btrfs_ioctl_ino_lookup_args {
__u64 objectid;
char name[BTRFS_INO_LOOKUP_PATH_MAX];
};
+static_assert(sizeof(struct btrfs_ioctl_ino_lookup_args) == 4096);
#define BTRFS_INO_LOOKUP_USER_PATH_MAX (4080 - BTRFS_VOL_NAME_MAX - 1)
struct btrfs_ioctl_ino_lookup_user_args {
@@ -475,6 +492,7 @@ struct btrfs_ioctl_ino_lookup_user_args {
*/
char path[BTRFS_INO_LOOKUP_USER_PATH_MAX];
};
+static_assert(sizeof(struct btrfs_ioctl_ino_lookup_user_args) == 4096);
/* Search criteria for the btrfs SEARCH ioctl family. */
struct btrfs_ioctl_search_key {
@@ -553,6 +571,7 @@ struct btrfs_ioctl_search_args {
struct btrfs_ioctl_search_key key;
char buf[BTRFS_SEARCH_ARGS_BUFSIZE];
};
+static_assert(sizeof(struct btrfs_ioctl_search_args) == 4096);
struct btrfs_ioctl_search_args_v2 {
struct btrfs_ioctl_search_key key; /* in/out - search parameters */
@@ -561,12 +580,14 @@ struct btrfs_ioctl_search_args_v2 {
* to store item */
__u64 buf[0]; /* out - found items */
};
+static_assert(sizeof(struct btrfs_ioctl_search_args_v2) == 112);
struct btrfs_ioctl_clone_range_args {
__s64 src_fd;
__u64 src_offset, src_length;
__u64 dest_offset;
};
+static_assert(sizeof(struct btrfs_ioctl_clone_range_args) == 32);
/*
* flags definition for the defrag range ioctl
@@ -606,7 +627,7 @@ struct btrfs_ioctl_defrag_range_args {
/* spare for later */
__u32 unused[4];
};
-
+static_assert(sizeof(struct btrfs_ioctl_defrag_range_args) == 48);
#define BTRFS_SAME_DATA_DIFFERS 1
/* For extent-same ioctl */
@@ -632,6 +653,7 @@ struct btrfs_ioctl_same_args {
__u32 reserved2;
struct btrfs_ioctl_same_extent_info info[0];
};
+static_assert(sizeof(struct btrfs_ioctl_same_args) == 24);
struct btrfs_ioctl_space_info {
__u64 flags;
@@ -644,6 +666,7 @@ struct btrfs_ioctl_space_args {
__u64 total_spaces;
struct btrfs_ioctl_space_info spaces[0];
};
+static_assert(sizeof(struct btrfs_ioctl_space_args) == 16);
struct btrfs_data_container {
__u32 bytes_left; /* out -- bytes not needed to deliver output */
@@ -660,6 +683,7 @@ struct btrfs_ioctl_ino_path_args {
/* struct btrfs_data_container *fspath; out */
__u64 fspath; /* out */
};
+static_assert(sizeof(struct btrfs_ioctl_ino_path_args) == 56);
struct btrfs_ioctl_logical_ino_args {
__u64 logical; /* in */
@@ -710,6 +734,7 @@ struct btrfs_ioctl_get_dev_stats {
*/
__u64 unused[128 - 2 - BTRFS_DEV_STAT_VALUES_MAX];
};
+static_assert(sizeof(struct btrfs_ioctl_get_dev_stats) == 1032);
#define BTRFS_QUOTA_CTL_ENABLE 1
#define BTRFS_QUOTA_CTL_DISABLE 2
@@ -718,12 +743,14 @@ struct btrfs_ioctl_quota_ctl_args {
__u64 cmd;
__u64 status;
};
+static_assert(sizeof(struct btrfs_ioctl_quota_ctl_args) == 16);
struct btrfs_ioctl_quota_rescan_args {
__u64 flags;
__u64 progress;
__u64 reserved[6];
};
+static_assert(sizeof(struct btrfs_ioctl_quota_rescan_args) == 64);
struct btrfs_ioctl_qgroup_assign_args {
__u64 assign;
@@ -735,6 +762,8 @@ struct btrfs_ioctl_qgroup_create_args {
__u64 create;
__u64 qgroupid;
};
+static_assert(sizeof(struct btrfs_ioctl_qgroup_create_args) == 16);
+
struct btrfs_ioctl_timespec {
__u64 sec;
__u32 nsec;
@@ -749,6 +778,7 @@ struct btrfs_ioctl_received_subvol_args {
__u64 flags; /* in */
__u64 reserved[16]; /* in */
};
+static_assert(sizeof(struct btrfs_ioctl_received_subvol_args) == 200);
/*
* Caller doesn't want file data in the send stream, even if the
@@ -783,6 +813,7 @@ struct btrfs_ioctl_send_args {
__u64 flags; /* in */
__u64 reserved[4]; /* in */
};
+static_assert(sizeof(struct btrfs_ioctl_send_args) == 72);
/*
* Information about a fs tree root.
@@ -859,6 +890,7 @@ struct btrfs_ioctl_get_subvol_rootref_args {
__u8 num_items;
__u8 align[7];
};
+static_assert(sizeof(struct btrfs_ioctl_get_subvol_rootref_args) == 4096);
/* Error codes as returned by the kernel */
enum btrfs_err_code {
--
2.26.2
