diff --git a/arch/riscv/include/uapi/asm/elf.h b/arch/riscv/include/uapi/asm/elf.h index 11a71b8533d575..d696d6610231dd 100644 --- a/arch/riscv/include/uapi/asm/elf.h +++ b/arch/riscv/include/uapi/asm/elf.h @@ -49,7 +49,6 @@ typedef union __riscv_fp_state elf_fpregset_t; #define R_RISCV_TLS_DTPREL64 9 #define R_RISCV_TLS_TPREL32 10 #define R_RISCV_TLS_TPREL64 11 -#define R_RISCV_IRELATIVE 58 /* Relocation types not used by the dynamic linker */ #define R_RISCV_BRANCH 16 @@ -82,6 +81,7 @@ typedef union __riscv_fp_state elf_fpregset_t; #define R_RISCV_ALIGN 43 #define R_RISCV_RVC_BRANCH 44 #define R_RISCV_RVC_JUMP 45 +#define R_RISCV_LUI 46 #define R_RISCV_GPREL_I 47 #define R_RISCV_GPREL_S 48 #define R_RISCV_TPREL_I 49 @@ -93,9 +93,6 @@ typedef union __riscv_fp_state elf_fpregset_t; #define R_RISCV_SET16 55 #define R_RISCV_SET32 56 #define R_RISCV_32_PCREL 57 -#define R_RISCV_PLT32 59 -#define R_RISCV_SET_ULEB128 60 -#define R_RISCV_SUB_ULEB128 61 #endif /* _UAPI_ASM_RISCV_ELF_H */ diff --git a/arch/riscv/kernel/module.c b/arch/riscv/kernel/module.c index 56a8c78e9e215e..8286d3bb04f473 100644 --- a/arch/riscv/kernel/module.c +++ b/arch/riscv/kernel/module.c @@ -7,9 +7,6 @@ #include #include #include -#include -#include -#include #include #include #include @@ -17,38 +14,6 @@ #include #include -struct used_bucket { - struct list_head head; - struct hlist_head *bucket; -}; - -struct relocation_head { - struct hlist_node node; - struct list_head *rel_entry; - void *location; -}; - -struct relocation_entry { - struct list_head head; - Elf_Addr value; - unsigned int type; -}; - -struct relocation_handlers { - int (*reloc_handler)(struct module *me, void *location, Elf_Addr v); - int (*accumulate_handler)(struct module *me, void *location, - long buffer); -}; - -unsigned int initialize_relocation_hashtable(unsigned int num_relocations); -void process_accumulated_relocations(struct module *me); -int add_relocation_to_accumulate(struct module *me, int type, void *location, - unsigned int hashtable_bits, Elf_Addr v); - -struct hlist_head *relocation_hashtable; - -struct list_head used_buckets_list; - /* * The auipc+jalr instruction pair can reach any PC-relative offset * in the range [-2^31 - 2^11, 2^31 - 2^11) @@ -308,12 +273,6 @@ static int apply_r_riscv_align_rela(struct module *me, void *location, return -EINVAL; } -static int apply_r_riscv_add8_rela(struct module *me, void *location, Elf_Addr v) -{ - *(u8 *)location += (u8)v; - return 0; -} - static int apply_r_riscv_add16_rela(struct module *me, void *location, Elf_Addr v) { @@ -335,12 +294,6 @@ static int apply_r_riscv_add64_rela(struct module *me, void *location, return 0; } -static int apply_r_riscv_sub8_rela(struct module *me, void *location, Elf_Addr v) -{ - *(u8 *)location -= (u8)v; - return 0; -} - static int apply_r_riscv_sub16_rela(struct module *me, void *location, Elf_Addr v) { @@ -362,374 +315,33 @@ static int apply_r_riscv_sub64_rela(struct module *me, void *location, return 0; } -static int dynamic_linking_not_supported(struct module *me, void *location, - Elf_Addr v) -{ - pr_err("%s: Dynamic linking not supported in kernel modules PC = %p\n", - me->name, location); - return -EINVAL; -} - -static int tls_not_supported(struct module *me, void *location, Elf_Addr v) -{ - pr_err("%s: Thread local storage not supported in kernel modules PC = %p\n", - me->name, location); - return -EINVAL; -} - -static int apply_r_riscv_sub6_rela(struct module *me, void *location, Elf_Addr v) -{ - u8 *byte = location; - u8 value = v; - - *byte = (*byte - (value & 0x3f)) & 0x3f; - return 0; -} - -static int apply_r_riscv_set6_rela(struct module *me, void *location, Elf_Addr v) -{ - u8 *byte = location; - u8 value = v; - - *byte = (*byte & 0xc0) | (value & 0x3f); - return 0; -} - -static int apply_r_riscv_set8_rela(struct module *me, void *location, Elf_Addr v) -{ - *(u8 *)location = (u8)v; - return 0; -} - -static int apply_r_riscv_set16_rela(struct module *me, void *location, - Elf_Addr v) -{ - *(u16 *)location = (u16)v; - return 0; -} - -static int apply_r_riscv_set32_rela(struct module *me, void *location, - Elf_Addr v) -{ - *(u32 *)location = (u32)v; - return 0; -} - -static int apply_r_riscv_32_pcrel_rela(struct module *me, void *location, - Elf_Addr v) -{ - *(u32 *)location = v - (uintptr_t)location; - return 0; -} - -static int apply_r_riscv_plt32_rela(struct module *me, void *location, - Elf_Addr v) -{ - ptrdiff_t offset = (void *)v - location; - - if (!riscv_insn_valid_32bit_offset(offset)) { - /* Only emit the plt entry if offset over 32-bit range */ - if (IS_ENABLED(CONFIG_MODULE_SECTIONS)) { - offset = (void *)module_emit_plt_entry(me, v) - location; - } else { - pr_err("%s: target %016llx can not be addressed by the 32-bit offset from PC = %p\n", - me->name, (long long)v, location); - return -EINVAL; - } - } - - *(u32 *)location = (u32)offset; - return 0; -} - -static int apply_r_riscv_set_uleb128(struct module *me, void *location, Elf_Addr v) -{ - *(long *)location = v; - return 0; -} - -static int apply_r_riscv_sub_uleb128(struct module *me, void *location, Elf_Addr v) -{ - *(long *)location -= v; - return 0; -} - -static int apply_6_bit_accumulation(struct module *me, void *location, long buffer) -{ - u8 *byte = location; - u8 value = buffer; - - if (buffer > 0x3f) { - pr_err("%s: value %ld out of range for 6-bit relocation.\n", - me->name, buffer); - return -EINVAL; - } - - *byte = (*byte & 0xc0) | (value & 0x3f); - return 0; -} - -static int apply_8_bit_accumulation(struct module *me, void *location, long buffer) -{ - if (buffer > U8_MAX) { - pr_err("%s: value %ld out of range for 8-bit relocation.\n", - me->name, buffer); - return -EINVAL; - } - *(u8 *)location = (u8)buffer; - return 0; -} - -static int apply_16_bit_accumulation(struct module *me, void *location, long buffer) -{ - if (buffer > U16_MAX) { - pr_err("%s: value %ld out of range for 16-bit relocation.\n", - me->name, buffer); - return -EINVAL; - } - *(u16 *)location = (u16)buffer; - return 0; -} - -static int apply_32_bit_accumulation(struct module *me, void *location, long buffer) -{ - if (buffer > U32_MAX) { - pr_err("%s: value %ld out of range for 32-bit relocation.\n", - me->name, buffer); - return -EINVAL; - } - *(u32 *)location = (u32)buffer; - return 0; -} - -static int apply_64_bit_accumulation(struct module *me, void *location, long buffer) -{ - *(u64 *)location = (u64)buffer; - return 0; -} - -static int apply_uleb128_accumulation(struct module *me, void *location, long buffer) -{ - /* - * ULEB128 is a variable length encoding. Encode the buffer into - * the ULEB128 data format. - */ - u8 *p = location; - - while (buffer != 0) { - u8 value = buffer & 0x7f; - - buffer >>= 7; - value |= (!!buffer) << 7; - - *p++ = value; - } - return 0; -} - -/* - * Relocations defined in the riscv-elf-psabi-doc. - * This handles static linking only. - */ -static const struct relocation_handlers reloc_handlers[] = { - [R_RISCV_32] = { .reloc_handler = apply_r_riscv_32_rela }, - [R_RISCV_64] = { .reloc_handler = apply_r_riscv_64_rela }, - [R_RISCV_RELATIVE] = { .reloc_handler = dynamic_linking_not_supported }, - [R_RISCV_COPY] = { .reloc_handler = dynamic_linking_not_supported }, - [R_RISCV_JUMP_SLOT] = { .reloc_handler = dynamic_linking_not_supported }, - [R_RISCV_TLS_DTPMOD32] = { .reloc_handler = dynamic_linking_not_supported }, - [R_RISCV_TLS_DTPMOD64] = { .reloc_handler = dynamic_linking_not_supported }, - [R_RISCV_TLS_DTPREL32] = { .reloc_handler = dynamic_linking_not_supported }, - [R_RISCV_TLS_DTPREL64] = { .reloc_handler = dynamic_linking_not_supported }, - [R_RISCV_TLS_TPREL32] = { .reloc_handler = dynamic_linking_not_supported }, - [R_RISCV_TLS_TPREL64] = { .reloc_handler = dynamic_linking_not_supported }, - /* 12-15 undefined */ - [R_RISCV_BRANCH] = { .reloc_handler = apply_r_riscv_branch_rela }, - [R_RISCV_JAL] = { .reloc_handler = apply_r_riscv_jal_rela }, - [R_RISCV_CALL] = { .reloc_handler = apply_r_riscv_call_rela }, - [R_RISCV_CALL_PLT] = { .reloc_handler = apply_r_riscv_call_plt_rela }, - [R_RISCV_GOT_HI20] = { .reloc_handler = apply_r_riscv_got_hi20_rela }, - [R_RISCV_TLS_GOT_HI20] = { .reloc_handler = tls_not_supported }, - [R_RISCV_TLS_GD_HI20] = { .reloc_handler = tls_not_supported }, - [R_RISCV_PCREL_HI20] = { .reloc_handler = apply_r_riscv_pcrel_hi20_rela }, - [R_RISCV_PCREL_LO12_I] = { .reloc_handler = apply_r_riscv_pcrel_lo12_i_rela }, - [R_RISCV_PCREL_LO12_S] = { .reloc_handler = apply_r_riscv_pcrel_lo12_s_rela }, - [R_RISCV_HI20] = { .reloc_handler = apply_r_riscv_hi20_rela }, - [R_RISCV_LO12_I] = { .reloc_handler = apply_r_riscv_lo12_i_rela }, - [R_RISCV_LO12_S] = { .reloc_handler = apply_r_riscv_lo12_s_rela }, - [R_RISCV_TPREL_HI20] = { .reloc_handler = tls_not_supported }, - [R_RISCV_TPREL_LO12_I] = { .reloc_handler = tls_not_supported }, - [R_RISCV_TPREL_LO12_S] = { .reloc_handler = tls_not_supported }, - [R_RISCV_TPREL_ADD] = { .reloc_handler = tls_not_supported }, - [R_RISCV_ADD8] = { .reloc_handler = apply_r_riscv_add8_rela, - .accumulate_handler = apply_8_bit_accumulation }, - [R_RISCV_ADD16] = { .reloc_handler = apply_r_riscv_add16_rela, - .accumulate_handler = apply_16_bit_accumulation }, - [R_RISCV_ADD32] = { .reloc_handler = apply_r_riscv_add32_rela, - .accumulate_handler = apply_32_bit_accumulation }, - [R_RISCV_ADD64] = { .reloc_handler = apply_r_riscv_add64_rela, - .accumulate_handler = apply_64_bit_accumulation }, - [R_RISCV_SUB8] = { .reloc_handler = apply_r_riscv_sub8_rela, - .accumulate_handler = apply_8_bit_accumulation }, - [R_RISCV_SUB16] = { .reloc_handler = apply_r_riscv_sub16_rela, - .accumulate_handler = apply_16_bit_accumulation }, - [R_RISCV_SUB32] = { .reloc_handler = apply_r_riscv_sub32_rela, - .accumulate_handler = apply_32_bit_accumulation }, - [R_RISCV_SUB64] = { .reloc_handler = apply_r_riscv_sub64_rela, - .accumulate_handler = apply_64_bit_accumulation }, - /* 41-42 reserved for future standard use */ - [R_RISCV_ALIGN] = { .reloc_handler = apply_r_riscv_align_rela }, - [R_RISCV_RVC_BRANCH] = { .reloc_handler = apply_r_riscv_rvc_branch_rela }, - [R_RISCV_RVC_JUMP] = { .reloc_handler = apply_r_riscv_rvc_jump_rela }, - /* 46-50 reserved for future standard use */ - [R_RISCV_RELAX] = { .reloc_handler = apply_r_riscv_relax_rela }, - [R_RISCV_SUB6] = { .reloc_handler = apply_r_riscv_sub6_rela, - .accumulate_handler = apply_6_bit_accumulation }, - [R_RISCV_SET6] = { .reloc_handler = apply_r_riscv_set6_rela, - .accumulate_handler = apply_6_bit_accumulation }, - [R_RISCV_SET8] = { .reloc_handler = apply_r_riscv_set8_rela, - .accumulate_handler = apply_8_bit_accumulation }, - [R_RISCV_SET16] = { .reloc_handler = apply_r_riscv_set16_rela, - .accumulate_handler = apply_16_bit_accumulation }, - [R_RISCV_SET32] = { .reloc_handler = apply_r_riscv_set32_rela, - .accumulate_handler = apply_32_bit_accumulation }, - [R_RISCV_32_PCREL] = { .reloc_handler = apply_r_riscv_32_pcrel_rela }, - [R_RISCV_IRELATIVE] = { .reloc_handler = dynamic_linking_not_supported }, - [R_RISCV_PLT32] = { .reloc_handler = apply_r_riscv_plt32_rela }, - [R_RISCV_SET_ULEB128] = { .reloc_handler = apply_r_riscv_set_uleb128, - .accumulate_handler = apply_uleb128_accumulation }, - [R_RISCV_SUB_ULEB128] = { .reloc_handler = apply_r_riscv_sub_uleb128, - .accumulate_handler = apply_uleb128_accumulation }, - /* 62-191 reserved for future standard use */ - /* 192-255 nonstandard ABI extensions */ +static int (*reloc_handlers_rela[]) (struct module *me, void *location, + Elf_Addr v) = { + [R_RISCV_32] = apply_r_riscv_32_rela, + [R_RISCV_64] = apply_r_riscv_64_rela, + [R_RISCV_BRANCH] = apply_r_riscv_branch_rela, + [R_RISCV_JAL] = apply_r_riscv_jal_rela, + [R_RISCV_RVC_BRANCH] = apply_r_riscv_rvc_branch_rela, + [R_RISCV_RVC_JUMP] = apply_r_riscv_rvc_jump_rela, + [R_RISCV_PCREL_HI20] = apply_r_riscv_pcrel_hi20_rela, + [R_RISCV_PCREL_LO12_I] = apply_r_riscv_pcrel_lo12_i_rela, + [R_RISCV_PCREL_LO12_S] = apply_r_riscv_pcrel_lo12_s_rela, + [R_RISCV_HI20] = apply_r_riscv_hi20_rela, + [R_RISCV_LO12_I] = apply_r_riscv_lo12_i_rela, + [R_RISCV_LO12_S] = apply_r_riscv_lo12_s_rela, + [R_RISCV_GOT_HI20] = apply_r_riscv_got_hi20_rela, + [R_RISCV_CALL_PLT] = apply_r_riscv_call_plt_rela, + [R_RISCV_CALL] = apply_r_riscv_call_rela, + [R_RISCV_RELAX] = apply_r_riscv_relax_rela, + [R_RISCV_ALIGN] = apply_r_riscv_align_rela, + [R_RISCV_ADD16] = apply_r_riscv_add16_rela, + [R_RISCV_ADD32] = apply_r_riscv_add32_rela, + [R_RISCV_ADD64] = apply_r_riscv_add64_rela, + [R_RISCV_SUB16] = apply_r_riscv_sub16_rela, + [R_RISCV_SUB32] = apply_r_riscv_sub32_rela, + [R_RISCV_SUB64] = apply_r_riscv_sub64_rela, }; -void process_accumulated_relocations(struct module *me) -{ - /* - * Only ADD/SUB/SET/ULEB128 should end up here. - * - * Each bucket may have more than one relocation location. All - * relocations for a location are stored in a list in a bucket. - * - * Relocations are applied to a temp variable before being stored to the - * provided location to check for overflow. This also allows ULEB128 to - * properly decide how many entries are needed before storing to - * location. The final value is stored into location using the handler - * for the last relocation to an address. - * - * Three layers of indexing: - * - Each of the buckets in use - * - Groups of relocations in each bucket by location address - * - Each relocation entry for a location address - */ - struct used_bucket *bucket_iter; - struct relocation_head *rel_head_iter; - struct relocation_entry *rel_entry_iter; - int curr_type; - void *location; - long buffer; - - list_for_each_entry(bucket_iter, &used_buckets_list, head) { - hlist_for_each_entry(rel_head_iter, bucket_iter->bucket, node) { - buffer = 0; - location = rel_head_iter->location; - list_for_each_entry(rel_entry_iter, - rel_head_iter->rel_entry, head) { - curr_type = rel_entry_iter->type; - reloc_handlers[curr_type].reloc_handler( - me, &buffer, rel_entry_iter->value); - kfree(rel_entry_iter); - } - reloc_handlers[curr_type].accumulate_handler( - me, location, buffer); - kfree(rel_head_iter); - } - kfree(bucket_iter); - } - - kfree(relocation_hashtable); -} - -int add_relocation_to_accumulate(struct module *me, int type, void *location, - unsigned int hashtable_bits, Elf_Addr v) -{ - struct relocation_entry *entry; - struct relocation_head *rel_head; - struct hlist_head *current_head; - struct used_bucket *bucket; - unsigned long hash; - - entry = kmalloc(sizeof(*entry), GFP_KERNEL); - INIT_LIST_HEAD(&entry->head); - entry->type = type; - entry->value = v; - - hash = hash_min((uintptr_t)location, hashtable_bits); - - current_head = &relocation_hashtable[hash]; - - /* Find matching location (if any) */ - bool found = false; - struct relocation_head *rel_head_iter; - - hlist_for_each_entry(rel_head_iter, current_head, node) { - if (rel_head_iter->location == location) { - found = true; - rel_head = rel_head_iter; - break; - } - } - - if (!found) { - rel_head = kmalloc(sizeof(*rel_head), GFP_KERNEL); - rel_head->rel_entry = - kmalloc(sizeof(struct list_head), GFP_KERNEL); - INIT_LIST_HEAD(rel_head->rel_entry); - rel_head->location = location; - INIT_HLIST_NODE(&rel_head->node); - if (!current_head->first) { - bucket = - kmalloc(sizeof(struct used_bucket), GFP_KERNEL); - INIT_LIST_HEAD(&bucket->head); - bucket->bucket = current_head; - list_add(&bucket->head, &used_buckets_list); - } - hlist_add_head(&rel_head->node, current_head); - } - - /* Add relocation to head of discovered rel_head */ - list_add_tail(&entry->head, rel_head->rel_entry); - - return 0; -} - -unsigned int initialize_relocation_hashtable(unsigned int num_relocations) -{ - /* Can safely assume that bits is not greater than sizeof(long) */ - unsigned long hashtable_size = roundup_pow_of_two(num_relocations); - unsigned int hashtable_bits = ilog2(hashtable_size); - - /* - * Double size of hashtable if num_relocations * 1.25 is greater than - * hashtable_size. - */ - int should_double_size = ((num_relocations + (num_relocations >> 2)) > (hashtable_size)); - - hashtable_bits += should_double_size; - - hashtable_size <<= should_double_size; - - relocation_hashtable = kmalloc_array(hashtable_size, - sizeof(*relocation_hashtable), - GFP_KERNEL); - __hash_init(relocation_hashtable, hashtable_size); - - INIT_LIST_HEAD(&used_buckets_list); - - return hashtable_bits; -} - int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab, unsigned int symindex, unsigned int relsec, struct module *me) @@ -741,13 +353,11 @@ int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab, unsigned int i, type; Elf_Addr v; int res; - unsigned int num_relocations = sechdrs[relsec].sh_size / sizeof(*rel); - unsigned int hashtable_bits = initialize_relocation_hashtable(num_relocations); pr_debug("Applying relocate section %u to %u\n", relsec, sechdrs[relsec].sh_info); - for (i = 0; i < num_relocations; i++) { + for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { /* This is where to make the change */ location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr + rel[i].r_offset; @@ -765,8 +375,8 @@ int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab, type = ELF_RISCV_R_TYPE(rel[i].r_info); - if (type < ARRAY_SIZE(reloc_handlers)) - handler = reloc_handlers[type].reloc_handler; + if (type < ARRAY_SIZE(reloc_handlers_rela)) + handler = reloc_handlers_rela[type]; else handler = NULL; @@ -822,16 +432,11 @@ int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab, } } - if (reloc_handlers[type].accumulate_handler) - res = add_relocation_to_accumulate(me, type, location, hashtable_bits, v); - else - res = handler(me, location, v); + res = handler(me, location, v); if (res) return res; } - process_accumulated_relocations(me); - return 0; }