diff options
Diffstat (limited to 'kernel/bpf/core.c')
| -rw-r--r-- | kernel/bpf/core.c | 89 |
1 files changed, 65 insertions, 24 deletions
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index ab630f773ec1..13e9dbeeedf3 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -33,6 +33,7 @@ #include <linux/extable.h> #include <linux/log2.h> #include <linux/bpf_verifier.h> +#include <linux/nodemask.h> #include <asm/barrier.h> #include <asm/unaligned.h> @@ -105,6 +106,7 @@ struct bpf_prog *bpf_prog_alloc_no_stats(unsigned int size, gfp_t gfp_extra_flag fp->aux = aux; fp->aux->prog = fp; fp->jit_requested = ebpf_jit_enabled(); + fp->blinding_requested = bpf_jit_blinding_enabled(fp); INIT_LIST_HEAD_RCU(&fp->aux->ksym.lnode); mutex_init(&fp->aux->used_maps_mutex); @@ -814,15 +816,9 @@ int bpf_jit_add_poke_descriptor(struct bpf_prog *prog, * allocator. The prog_pack allocator uses HPAGE_PMD_SIZE page (2MB on x86) * to host BPF programs. */ -#ifdef CONFIG_TRANSPARENT_HUGEPAGE -#define BPF_PROG_PACK_SIZE HPAGE_PMD_SIZE -#else -#define BPF_PROG_PACK_SIZE PAGE_SIZE -#endif #define BPF_PROG_CHUNK_SHIFT 6 #define BPF_PROG_CHUNK_SIZE (1 << BPF_PROG_CHUNK_SHIFT) #define BPF_PROG_CHUNK_MASK (~(BPF_PROG_CHUNK_SIZE - 1)) -#define BPF_PROG_CHUNK_COUNT (BPF_PROG_PACK_SIZE / BPF_PROG_CHUNK_SIZE) struct bpf_prog_pack { struct list_head list; @@ -830,30 +826,72 @@ struct bpf_prog_pack { unsigned long bitmap[]; }; -#define BPF_PROG_MAX_PACK_PROG_SIZE BPF_PROG_PACK_SIZE #define BPF_PROG_SIZE_TO_NBITS(size) (round_up(size, BPF_PROG_CHUNK_SIZE) / BPF_PROG_CHUNK_SIZE) +static size_t bpf_prog_pack_size = -1; +static size_t bpf_prog_pack_mask = -1; + +static int bpf_prog_chunk_count(void) +{ + WARN_ON_ONCE(bpf_prog_pack_size == -1); + return bpf_prog_pack_size / BPF_PROG_CHUNK_SIZE; +} + static DEFINE_MUTEX(pack_mutex); static LIST_HEAD(pack_list); +/* PMD_SIZE is not available in some special config, e.g. ARCH=arm with + * CONFIG_MMU=n. Use PAGE_SIZE in these cases. + */ +#ifdef PMD_SIZE +#define BPF_HPAGE_SIZE PMD_SIZE +#define BPF_HPAGE_MASK PMD_MASK +#else +#define BPF_HPAGE_SIZE PAGE_SIZE +#define BPF_HPAGE_MASK PAGE_MASK +#endif + +static size_t select_bpf_prog_pack_size(void) +{ + size_t size; + void *ptr; + + size = BPF_HPAGE_SIZE * num_online_nodes(); + ptr = module_alloc(size); + + /* Test whether we can get huge pages. If not just use PAGE_SIZE + * packs. + */ + if (!ptr || !is_vm_area_hugepages(ptr)) { + size = PAGE_SIZE; + bpf_prog_pack_mask = PAGE_MASK; + } else { + bpf_prog_pack_mask = BPF_HPAGE_MASK; + } + + vfree(ptr); + return size; +} + static struct bpf_prog_pack *alloc_new_pack(void) { struct bpf_prog_pack *pack; - pack = kzalloc(sizeof(*pack) + BITS_TO_BYTES(BPF_PROG_CHUNK_COUNT), GFP_KERNEL); + pack = kzalloc(struct_size(pack, bitmap, BITS_TO_LONGS(bpf_prog_chunk_count())), + GFP_KERNEL); if (!pack) return NULL; - pack->ptr = module_alloc(BPF_PROG_PACK_SIZE); + pack->ptr = module_alloc(bpf_prog_pack_size); if (!pack->ptr) { kfree(pack); return NULL; } - bitmap_zero(pack->bitmap, BPF_PROG_PACK_SIZE / BPF_PROG_CHUNK_SIZE); + bitmap_zero(pack->bitmap, bpf_prog_pack_size / BPF_PROG_CHUNK_SIZE); list_add_tail(&pack->list, &pack_list); set_vm_flush_reset_perms(pack->ptr); - set_memory_ro((unsigned long)pack->ptr, BPF_PROG_PACK_SIZE / PAGE_SIZE); - set_memory_x((unsigned long)pack->ptr, BPF_PROG_PACK_SIZE / PAGE_SIZE); + set_memory_ro((unsigned long)pack->ptr, bpf_prog_pack_size / PAGE_SIZE); + set_memory_x((unsigned long)pack->ptr, bpf_prog_pack_size / PAGE_SIZE); return pack; } @@ -864,7 +902,11 @@ static void *bpf_prog_pack_alloc(u32 size) unsigned long pos; void *ptr = NULL; - if (size > BPF_PROG_MAX_PACK_PROG_SIZE) { + mutex_lock(&pack_mutex); + if (bpf_prog_pack_size == -1) + bpf_prog_pack_size = select_bpf_prog_pack_size(); + + if (size > bpf_prog_pack_size) { size = round_up(size, PAGE_SIZE); ptr = module_alloc(size); if (ptr) { @@ -872,13 +914,12 @@ static void *bpf_prog_pack_alloc(u32 size) set_memory_ro((unsigned long)ptr, size / PAGE_SIZE); set_memory_x((unsigned long)ptr, size / PAGE_SIZE); } - return ptr; + goto out; } - mutex_lock(&pack_mutex); list_for_each_entry(pack, &pack_list, list) { - pos = bitmap_find_next_zero_area(pack->bitmap, BPF_PROG_CHUNK_COUNT, 0, + pos = bitmap_find_next_zero_area(pack->bitmap, bpf_prog_chunk_count(), 0, nbits, 0); - if (pos < BPF_PROG_CHUNK_COUNT) + if (pos < bpf_prog_chunk_count()) goto found_free_area; } @@ -904,13 +945,13 @@ static void bpf_prog_pack_free(struct bpf_binary_header *hdr) unsigned long pos; void *pack_ptr; - if (hdr->size > BPF_PROG_MAX_PACK_PROG_SIZE) { + mutex_lock(&pack_mutex); + if (hdr->size > bpf_prog_pack_size) { module_memfree(hdr); - return; + goto out; } - pack_ptr = (void *)((unsigned long)hdr & ~(BPF_PROG_PACK_SIZE - 1)); - mutex_lock(&pack_mutex); + pack_ptr = (void *)((unsigned long)hdr & bpf_prog_pack_mask); list_for_each_entry(tmp, &pack_list, list) { if (tmp->ptr == pack_ptr) { @@ -926,8 +967,8 @@ static void bpf_prog_pack_free(struct bpf_binary_header *hdr) pos = ((unsigned long)hdr - (unsigned long)pack_ptr) >> BPF_PROG_CHUNK_SHIFT; bitmap_clear(pack->bitmap, pos, nbits); - if (bitmap_find_next_zero_area(pack->bitmap, BPF_PROG_CHUNK_COUNT, 0, - BPF_PROG_CHUNK_COUNT, 0) == 0) { + if (bitmap_find_next_zero_area(pack->bitmap, bpf_prog_chunk_count(), 0, + bpf_prog_chunk_count(), 0) == 0) { list_del(&pack->list); module_memfree(pack->ptr); kfree(pack); @@ -1382,7 +1423,7 @@ struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *prog) struct bpf_insn *insn; int i, rewritten; - if (!bpf_jit_blinding_enabled(prog) || prog->blinded) + if (!prog->blinding_requested || prog->blinded) return prog; clone = bpf_prog_clone_create(prog, GFP_USER); |