diff options
| author | Song Liu <songliubraving@fb.com> | 2022-02-04 10:57:35 -0800 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2022-02-07 18:13:01 -0800 |
| commit | 3486bedd99196ecdfe99c0ab5b67ad3c47e8a8fa (patch) | |
| tree | 14f258f23c25f941a2f33f9ff0b09587aa8e8028 /kernel | |
| parent | fac54e2bfb5be2b0bbf115fe80d45f59fd773048 (diff) | |
| download | lwn-3486bedd99196ecdfe99c0ab5b67ad3c47e8a8fa.tar.gz lwn-3486bedd99196ecdfe99c0ab5b67ad3c47e8a8fa.zip | |
bpf: Use bytes instead of pages for bpf_jit_[charge|uncharge]_modmem
This enables sub-page memory charge and allocation.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220204185742.271030-3-song@kernel.org
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/bpf/core.c | 17 | ||||
| -rw-r--r-- | kernel/bpf/trampoline.c | 6 |
2 files changed, 11 insertions, 12 deletions
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 04a8d5bea552..6ca0550c4b24 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -833,12 +833,11 @@ static int __init bpf_jit_charge_init(void) } pure_initcall(bpf_jit_charge_init); -int bpf_jit_charge_modmem(u32 pages) +int bpf_jit_charge_modmem(u32 size) { - if (atomic_long_add_return(pages, &bpf_jit_current) > - (bpf_jit_limit >> PAGE_SHIFT)) { + if (atomic_long_add_return(size, &bpf_jit_current) > bpf_jit_limit) { if (!bpf_capable()) { - atomic_long_sub(pages, &bpf_jit_current); + atomic_long_sub(size, &bpf_jit_current); return -EPERM; } } @@ -846,9 +845,9 @@ int bpf_jit_charge_modmem(u32 pages) return 0; } -void bpf_jit_uncharge_modmem(u32 pages) +void bpf_jit_uncharge_modmem(u32 size) { - atomic_long_sub(pages, &bpf_jit_current); + atomic_long_sub(size, &bpf_jit_current); } void *__weak bpf_jit_alloc_exec(unsigned long size) @@ -879,11 +878,11 @@ bpf_jit_binary_alloc(unsigned int proglen, u8 **image_ptr, size = round_up(proglen + sizeof(*hdr) + 128, PAGE_SIZE); pages = size / PAGE_SIZE; - if (bpf_jit_charge_modmem(pages)) + if (bpf_jit_charge_modmem(size)) return NULL; hdr = bpf_jit_alloc_exec(size); if (!hdr) { - bpf_jit_uncharge_modmem(pages); + bpf_jit_uncharge_modmem(size); return NULL; } @@ -906,7 +905,7 @@ void bpf_jit_binary_free(struct bpf_binary_header *hdr) u32 pages = hdr->pages; bpf_jit_free_exec(hdr); - bpf_jit_uncharge_modmem(pages); + bpf_jit_uncharge_modmem(pages << PAGE_SHIFT); } /* This symbol is only overridden by archs that have different diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c index 4b6974a195c1..e76a488c09c3 100644 --- a/kernel/bpf/trampoline.c +++ b/kernel/bpf/trampoline.c @@ -213,7 +213,7 @@ static void __bpf_tramp_image_put_deferred(struct work_struct *work) im = container_of(work, struct bpf_tramp_image, work); bpf_image_ksym_del(&im->ksym); bpf_jit_free_exec(im->image); - bpf_jit_uncharge_modmem(1); + bpf_jit_uncharge_modmem(PAGE_SIZE); percpu_ref_exit(&im->pcref); kfree_rcu(im, rcu); } @@ -310,7 +310,7 @@ static struct bpf_tramp_image *bpf_tramp_image_alloc(u64 key, u32 idx) if (!im) goto out; - err = bpf_jit_charge_modmem(1); + err = bpf_jit_charge_modmem(PAGE_SIZE); if (err) goto out_free_im; @@ -332,7 +332,7 @@ static struct bpf_tramp_image *bpf_tramp_image_alloc(u64 key, u32 idx) out_free_image: bpf_jit_free_exec(im->image); out_uncharge: - bpf_jit_uncharge_modmem(1); + bpf_jit_uncharge_modmem(PAGE_SIZE); out_free_im: kfree(im); out: |