From: Gyutae Bae <[email protected]> Introduce the UAPI surface for a compare-and-delete primitive: a new map flag BPF_F_COMPARE plus compare/compare_offset/compare_size fields let a delete request name an expected value region. Behaviour is wired up in the following patch; this adds the flag and fields (kernel + tools/ copy) only.
Co-developed-by: Minsu Jeon <[email protected]> Signed-off-by: Minsu Jeon <[email protected]> Co-developed-by: Siwan Kim <[email protected]> Signed-off-by: Siwan Kim <[email protected]> Co-developed-by: Jonghyeon Kim <[email protected]> Signed-off-by: Jonghyeon Kim <[email protected]> Signed-off-by: Gyutae Bae <[email protected]> --- include/uapi/linux/bpf.h | 6 +++++- tools/include/uapi/linux/bpf.h | 6 +++++- 2 files changed, 10 insertions(+), 2 deletions(-) diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 89b36de5fdbb..4705b02fb6a4 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -1397,7 +1397,7 @@ enum bpf_addr_space_cast { BPF_ADDR_SPACE_CAST = 1, }; -/* flags for BPF_MAP_UPDATE_ELEM command */ +/* flags for BPF_MAP_UPDATE_ELEM / BPF_MAP_DELETE_ELEM commands */ enum { BPF_ANY = 0, /* create new element or update existing */ BPF_NOEXIST = 1, /* create new element if it didn't exist */ @@ -1405,6 +1405,7 @@ enum { BPF_F_LOCK = 4, /* spin_lock-ed map_lookup/map_update */ BPF_F_CPU = 8, /* cpu flag for percpu maps, upper 32-bit of flags is a cpu number */ BPF_F_ALL_CPUS = 16, /* update value across all CPUs for percpu maps */ + BPF_F_COMPARE = 32, /* compare-and-delete: delete elem only if value region == compare */ }; /* flags for BPF_MAP_CREATE command */ @@ -1586,6 +1587,9 @@ union bpf_attr { __aligned_u64 next_key; }; __u64 flags; + __aligned_u64 compare; /* user ptr to expected bytes (BPF_F_COMPARE) */ + __u32 compare_offset; /* start offset within value */ + __u32 compare_size; /* bytes to compare; 0 == whole value */ }; struct { /* struct used by BPF_MAP_*_BATCH commands */ diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 89b36de5fdbb..4705b02fb6a4 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -1397,7 +1397,7 @@ enum bpf_addr_space_cast { BPF_ADDR_SPACE_CAST = 1, }; -/* flags for BPF_MAP_UPDATE_ELEM command */ +/* flags for BPF_MAP_UPDATE_ELEM / BPF_MAP_DELETE_ELEM commands */ enum { BPF_ANY = 0, /* create new element or update existing */ BPF_NOEXIST = 1, /* create new element if it didn't exist */ @@ -1405,6 +1405,7 @@ enum { BPF_F_LOCK = 4, /* spin_lock-ed map_lookup/map_update */ BPF_F_CPU = 8, /* cpu flag for percpu maps, upper 32-bit of flags is a cpu number */ BPF_F_ALL_CPUS = 16, /* update value across all CPUs for percpu maps */ + BPF_F_COMPARE = 32, /* compare-and-delete: delete elem only if value region == compare */ }; /* flags for BPF_MAP_CREATE command */ @@ -1586,6 +1587,9 @@ union bpf_attr { __aligned_u64 next_key; }; __u64 flags; + __aligned_u64 compare; /* user ptr to expected bytes (BPF_F_COMPARE) */ + __u32 compare_offset; /* start offset within value */ + __u32 compare_size; /* bytes to compare; 0 == whole value */ }; struct { /* struct used by BPF_MAP_*_BATCH commands */ -- 2.39.5 (Apple Git-154)
