| Message ID | 20200702014001.37945-1-alexei.starovoitov@gmail.com |
|---|---|
| State | Changes Requested |
| Delegated to: | BPF Maintainers |
| Headers | show |
| Series | [bpf-next] bpf: Add bpf_prog iterator | expand |
On 7/1/20 6:40 PM, Alexei Starovoitov wrote: > From: Alexei Starovoitov <ast@kernel.org> > > It's mostly a copy paste of commit 6086d29def80 ("bpf: Add bpf_map iterator") > that is use to implement bpf_seq_file opreations to traverse all bpf programs. Thanks for implementing bpf iter for bpf_progs! > > Signed-off-by: Alexei Starovoitov <ast@kernel.org> > --- > No selftests?! > They're coming as part of "usermode_driver for iterators" set. > This patch is trivial and independent, so sending it first. Okay. Ack only with a few nits. Acked-by: Yonghong Song <yhs@fb.com> > > include/linux/bpf.h | 1 + > kernel/bpf/Makefile | 2 +- > kernel/bpf/prog_iter.c | 102 +++++++++++++++++++++++++++++++++++++++++ > kernel/bpf/syscall.c | 19 ++++++++ > 4 files changed, 123 insertions(+), 1 deletion(-) > create mode 100644 kernel/bpf/prog_iter.c > > diff --git a/include/linux/bpf.h b/include/linux/bpf.h > index 0cd7f6884c5c..3c659f36591d 100644 > --- a/include/linux/bpf.h > +++ b/include/linux/bpf.h > @@ -1112,6 +1112,7 @@ int generic_map_delete_batch(struct bpf_map *map, > const union bpf_attr *attr, > union bpf_attr __user *uattr); > struct bpf_map *bpf_map_get_curr_or_next(u32 *id); > +struct bpf_prog *bpf_prog_get_curr_or_next(u32 *id); > > extern int sysctl_unprivileged_bpf_disabled; > > diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile > index 1131a921e1a6..e6eb9c0402da 100644 > --- a/kernel/bpf/Makefile > +++ b/kernel/bpf/Makefile > @@ -2,7 +2,7 @@ > obj-y := core.o > CFLAGS_core.o += $(call cc-disable-warning, override-init) > > -obj-$(CONFIG_BPF_SYSCALL) += syscall.o verifier.o inode.o helpers.o tnum.o bpf_iter.o map_iter.o task_iter.o > +obj-$(CONFIG_BPF_SYSCALL) += syscall.o verifier.o inode.o helpers.o tnum.o bpf_iter.o map_iter.o task_iter.o prog_iter.o > obj-$(CONFIG_BPF_SYSCALL) += hashtab.o arraymap.o percpu_freelist.o bpf_lru_list.o lpm_trie.o map_in_map.o > obj-$(CONFIG_BPF_SYSCALL) += local_storage.o queue_stack_maps.o ringbuf.o > obj-$(CONFIG_BPF_SYSCALL) += disasm.o > diff --git a/kernel/bpf/prog_iter.c b/kernel/bpf/prog_iter.c > new file mode 100644 > index 000000000000..3080abd4d8ad > --- /dev/null > +++ b/kernel/bpf/prog_iter.c > @@ -0,0 +1,102 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* Copyright (c) 2020 Facebook */ > +#include <linux/bpf.h> > +#include <linux/fs.h> > +#include <linux/filter.h> > +#include <linux/kernel.h> > + > +struct bpf_iter_seq_prog_info { > + u32 mid; original field name "mid" is for "map_id". Here, "pid" is a little bit misleading, maybe "prog_id"? > +}; > + > +static void *bpf_prog_seq_start(struct seq_file *seq, loff_t *pos) > +{ > + struct bpf_iter_seq_prog_info *info = seq->private; > + struct bpf_prog *prog; > + > + prog = bpf_prog_get_curr_or_next(&info->mid); > + if (!prog) > + return NULL; > + > + ++*pos; > + return prog; > +} > + > +static void *bpf_prog_seq_next(struct seq_file *seq, void *v, loff_t *pos) > +{ > + struct bpf_iter_seq_prog_info *info = seq->private; > + struct bpf_prog *prog; > + > + ++*pos; > + ++info->mid; > + bpf_prog_put((struct bpf_prog *)v); > + prog = bpf_prog_get_curr_or_next(&info->mid); > + if (!prog) > + return NULL; > + > + return prog; You can just do "return bpf_prog_get_curr_or_next(&info->prog_id);" "struct bpf_prog *prog" is not needed any more. bpf_map_seq_next() has the same inefficiency. I think after a few revisions I lost the sight. > +} > + > +struct bpf_iter__bpf_prog { > + __bpf_md_ptr(struct bpf_iter_meta *, meta); > + __bpf_md_ptr(struct bpf_prog *, prog); > +}; > + > +DEFINE_BPF_ITER_FUNC(bpf_prog, struct bpf_iter_meta *meta, struct bpf_prog *prog) > + > +static int __bpf_prog_seq_show(struct seq_file *seq, void *v, bool in_stop) > +{ > + struct bpf_iter__bpf_prog ctx; > + struct bpf_iter_meta meta; > + struct bpf_prog *prog; > + int ret = 0; > + > + ctx.meta = &meta; > + ctx.prog = v; > + meta.seq = seq; > + prog = bpf_iter_get_info(&meta, in_stop); > + if (prog) > + ret = bpf_iter_run_prog(prog, &ctx); > + > + return ret; > +} > + [...]
On Wed, Jul 1, 2020 at 10:23 PM Yonghong Song <yhs@fb.com> wrote: > > > > On 7/1/20 6:40 PM, Alexei Starovoitov wrote: > > From: Alexei Starovoitov <ast@kernel.org> > > > > It's mostly a copy paste of commit 6086d29def80 ("bpf: Add bpf_map iterator") > > that is use to implement bpf_seq_file opreations to traverse all bpf programs. > > Thanks for implementing bpf iter for bpf_progs! > > > > > Signed-off-by: Alexei Starovoitov <ast@kernel.org> > > --- > > No selftests?! > > They're coming as part of "usermode_driver for iterators" set. > > This patch is trivial and independent, so sending it first. > > Okay. Ack only with a few nits. > Acked-by: Yonghong Song <yhs@fb.com> Thanks for the review. Will be fixed in the next version.
diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 0cd7f6884c5c..3c659f36591d 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -1112,6 +1112,7 @@ int generic_map_delete_batch(struct bpf_map *map, const union bpf_attr *attr, union bpf_attr __user *uattr); struct bpf_map *bpf_map_get_curr_or_next(u32 *id); +struct bpf_prog *bpf_prog_get_curr_or_next(u32 *id); extern int sysctl_unprivileged_bpf_disabled; diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile index 1131a921e1a6..e6eb9c0402da 100644 --- a/kernel/bpf/Makefile +++ b/kernel/bpf/Makefile @@ -2,7 +2,7 @@ obj-y := core.o CFLAGS_core.o += $(call cc-disable-warning, override-init) -obj-$(CONFIG_BPF_SYSCALL) += syscall.o verifier.o inode.o helpers.o tnum.o bpf_iter.o map_iter.o task_iter.o +obj-$(CONFIG_BPF_SYSCALL) += syscall.o verifier.o inode.o helpers.o tnum.o bpf_iter.o map_iter.o task_iter.o prog_iter.o obj-$(CONFIG_BPF_SYSCALL) += hashtab.o arraymap.o percpu_freelist.o bpf_lru_list.o lpm_trie.o map_in_map.o obj-$(CONFIG_BPF_SYSCALL) += local_storage.o queue_stack_maps.o ringbuf.o obj-$(CONFIG_BPF_SYSCALL) += disasm.o diff --git a/kernel/bpf/prog_iter.c b/kernel/bpf/prog_iter.c new file mode 100644 index 000000000000..3080abd4d8ad --- /dev/null +++ b/kernel/bpf/prog_iter.c @@ -0,0 +1,102 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright (c) 2020 Facebook */ +#include <linux/bpf.h> +#include <linux/fs.h> +#include <linux/filter.h> +#include <linux/kernel.h> + +struct bpf_iter_seq_prog_info { + u32 mid; +}; + +static void *bpf_prog_seq_start(struct seq_file *seq, loff_t *pos) +{ + struct bpf_iter_seq_prog_info *info = seq->private; + struct bpf_prog *prog; + + prog = bpf_prog_get_curr_or_next(&info->mid); + if (!prog) + return NULL; + + ++*pos; + return prog; +} + +static void *bpf_prog_seq_next(struct seq_file *seq, void *v, loff_t *pos) +{ + struct bpf_iter_seq_prog_info *info = seq->private; + struct bpf_prog *prog; + + ++*pos; + ++info->mid; + bpf_prog_put((struct bpf_prog *)v); + prog = bpf_prog_get_curr_or_next(&info->mid); + if (!prog) + return NULL; + + return prog; +} + +struct bpf_iter__bpf_prog { + __bpf_md_ptr(struct bpf_iter_meta *, meta); + __bpf_md_ptr(struct bpf_prog *, prog); +}; + +DEFINE_BPF_ITER_FUNC(bpf_prog, struct bpf_iter_meta *meta, struct bpf_prog *prog) + +static int __bpf_prog_seq_show(struct seq_file *seq, void *v, bool in_stop) +{ + struct bpf_iter__bpf_prog ctx; + struct bpf_iter_meta meta; + struct bpf_prog *prog; + int ret = 0; + + ctx.meta = &meta; + ctx.prog = v; + meta.seq = seq; + prog = bpf_iter_get_info(&meta, in_stop); + if (prog) + ret = bpf_iter_run_prog(prog, &ctx); + + return ret; +} + +static int bpf_prog_seq_show(struct seq_file *seq, void *v) +{ + return __bpf_prog_seq_show(seq, v, false); +} + +static void bpf_prog_seq_stop(struct seq_file *seq, void *v) +{ + if (!v) + (void)__bpf_prog_seq_show(seq, v, true); + else + bpf_prog_put((struct bpf_prog *)v); +} + +static const struct seq_operations bpf_prog_seq_ops = { + .start = bpf_prog_seq_start, + .next = bpf_prog_seq_next, + .stop = bpf_prog_seq_stop, + .show = bpf_prog_seq_show, +}; + +static const struct bpf_iter_reg bpf_prog_reg_info = { + .target = "bpf_prog", + .seq_ops = &bpf_prog_seq_ops, + .init_seq_private = NULL, + .fini_seq_private = NULL, + .seq_priv_size = sizeof(struct bpf_iter_seq_prog_info), + .ctx_arg_info_size = 1, + .ctx_arg_info = { + { offsetof(struct bpf_iter__bpf_prog, prog), + PTR_TO_BTF_ID_OR_NULL }, + }, +}; + +static int __init bpf_prog_iter_init(void) +{ + return bpf_iter_reg_target(&bpf_prog_reg_info); +} + +late_initcall(bpf_prog_iter_init); diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 8da159936bab..e236a6c0aea4 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -3035,6 +3035,25 @@ struct bpf_map *bpf_map_get_curr_or_next(u32 *id) return map; } +struct bpf_prog *bpf_prog_get_curr_or_next(u32 *id) +{ + struct bpf_prog *prog; + + spin_lock_bh(&prog_idr_lock); +again: + prog = idr_get_next(&prog_idr, id); + if (prog) { + prog = bpf_prog_inc_not_zero(prog); + if (IS_ERR(prog)) { + (*id)++; + goto again; + } + } + spin_unlock_bh(&prog_idr_lock); + + return prog; +} + #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id struct bpf_prog *bpf_prog_by_id(u32 id)