This new ioctl call allows the user to supply a buffer of varying size in which a tree search can store its results. This is much more flexible if you want to receive items which are larger than the current fixed buffer of 3992 bytes or if you want to fetch more items at once. Items larger than this buffer are for example some of the type EXTENT_CSUM.
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| @@ -306,6 +306,14 @@ struct btrfs_ioctl_search_args { · 305 unmodified lines | ||
| 306 | 306 | char buf[BTRFS_SEARCH_ARGS_BUFSIZE]; |
| 307 | 307 | }; |
| 308 | 308 | |
| 309 | +struct btrfs_ioctl_search_args_v2 { | |
| 310 | + struct btrfs_ioctl_search_key key; /* in/out - search parameters */ | |
| 311 | + __u64 buf_size; /* in - size of buffer | |
| 312 | + * out - on EOVERFLOW: needed size | |
| 313 | + * to store item */ | |
| 314 | + __u64 buf[0]; /* out - found items */ | |
| 315 | +}; | |
| 316 | + | |
| 309 | 317 | struct btrfs_ioctl_clone_range_args { |
| 310 | 318 | __s64 src_fd; |
| 311 | 319 | __u64 src_offset, src_length; |
| @@ -558,6 +566,8 @@ static inline char *btrfs_err_str(enum btrfs_err_code err_code) · 246 unmodified lines | ||
| 558 | 566 | struct btrfs_ioctl_defrag_range_args) |
| 559 | 567 | #define BTRFS_IOC_TREE_SEARCH _IOWR(BTRFS_IOCTL_MAGIC, 17, \ |
| 560 | 568 | struct btrfs_ioctl_search_args) |
| 569 | +#define BTRFS_IOC_TREE_SEARCH_V2 _IOWR(BTRFS_IOCTL_MAGIC, 17, \ | |
| 570 | + struct btrfs_ioctl_search_args_v2) | |
| 561 | 571 | #define BTRFS_IOC_INO_LOOKUP _IOWR(BTRFS_IOCTL_MAGIC, 18, \ |
| 562 | 572 | struct btrfs_ioctl_ino_lookup_args) |
| 563 | 573 | #define BTRFS_IOC_DEFAULT_SUBVOL _IOW(BTRFS_IOCTL_MAGIC, 19, __u64) |