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Diffstat (limited to 'arch/parisc/kernel/module.c')
| -rw-r--r-- | arch/parisc/kernel/module.c | 973 |
1 files changed, 973 insertions, 0 deletions
diff --git a/arch/parisc/kernel/module.c b/arch/parisc/kernel/module.c new file mode 100644 index 0000000000..d214bbe3c2 --- /dev/null +++ b/arch/parisc/kernel/module.c @@ -0,0 +1,973 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* Kernel dynamically loadable module help for PARISC. + * + * The best reference for this stuff is probably the Processor- + * Specific ELF Supplement for PA-RISC: + * https://parisc.wiki.kernel.org/index.php/File:Elf-pa-hp.pdf + * + * Linux/PA-RISC Project + * Copyright (C) 2003 Randolph Chung <tausq at debian . org> + * Copyright (C) 2008 Helge Deller <deller@gmx.de> + * + * Notes: + * - PLT stub handling + * On 32bit (and sometimes 64bit) and with big kernel modules like xfs or + * ipv6 the relocation types R_PARISC_PCREL17F and R_PARISC_PCREL22F may + * fail to reach their PLT stub if we only create one big stub array for + * all sections at the beginning of the core or init section. + * Instead we now insert individual PLT stub entries directly in front of + * of the code sections where the stubs are actually called. + * This reduces the distance between the PCREL location and the stub entry + * so that the relocations can be fulfilled. + * While calculating the final layout of the kernel module in memory, the + * kernel module loader calls arch_mod_section_prepend() to request the + * to be reserved amount of memory in front of each individual section. + * + * - SEGREL32 handling + * We are not doing SEGREL32 handling correctly. According to the ABI, we + * should do a value offset, like this: + * if (in_init(me, (void *)val)) + * val -= (uint32_t)me->mem[MOD_INIT_TEXT].base; + * else + * val -= (uint32_t)me->mem[MOD_TEXT].base; + * However, SEGREL32 is used only for PARISC unwind entries, and we want + * those entries to have an absolute address, and not just an offset. + * + * The unwind table mechanism has the ability to specify an offset for + * the unwind table; however, because we split off the init functions into + * a different piece of memory, it is not possible to do this using a + * single offset. Instead, we use the above hack for now. + */ + +#include <linux/moduleloader.h> +#include <linux/elf.h> +#include <linux/vmalloc.h> +#include <linux/fs.h> +#include <linux/ftrace.h> +#include <linux/string.h> +#include <linux/kernel.h> +#include <linux/bug.h> +#include <linux/mm.h> +#include <linux/slab.h> + +#include <asm/unwind.h> +#include <asm/sections.h> + +#define RELOC_REACHABLE(val, bits) \ + (( ( !((val) & (1<<((bits)-1))) && ((val)>>(bits)) != 0 ) || \ + ( ((val) & (1<<((bits)-1))) && ((val)>>(bits)) != (((__typeof__(val))(~0))>>((bits)+2)))) ? \ + 0 : 1) + +#define CHECK_RELOC(val, bits) \ + if (!RELOC_REACHABLE(val, bits)) { \ + printk(KERN_ERR "module %s relocation of symbol %s is out of range (0x%lx in %d bits)\n", \ + me->name, strtab + sym->st_name, (unsigned long)val, bits); \ + return -ENOEXEC; \ + } + +/* Maximum number of GOT entries. We use a long displacement ldd from + * the bottom of the table, which has a maximum signed displacement of + * 0x3fff; however, since we're only going forward, this becomes + * 0x1fff, and thus, since each GOT entry is 8 bytes long we can have + * at most 1023 entries. + * To overcome this 14bit displacement with some kernel modules, we'll + * use instead the unusal 16bit displacement method (see reassemble_16a) + * which gives us a maximum positive displacement of 0x7fff, and as such + * allows us to allocate up to 4095 GOT entries. */ +#define MAX_GOTS 4095 + +#ifndef CONFIG_64BIT +struct got_entry { + Elf32_Addr addr; +}; + +struct stub_entry { + Elf32_Word insns[2]; /* each stub entry has two insns */ +}; +#else +struct got_entry { + Elf64_Addr addr; +}; + +struct stub_entry { + Elf64_Word insns[4]; /* each stub entry has four insns */ +}; +#endif + +/* Field selection types defined by hppa */ +#define rnd(x) (((x)+0x1000)&~0x1fff) +/* fsel: full 32 bits */ +#define fsel(v,a) ((v)+(a)) +/* lsel: select left 21 bits */ +#define lsel(v,a) (((v)+(a))>>11) +/* rsel: select right 11 bits */ +#define rsel(v,a) (((v)+(a))&0x7ff) +/* lrsel with rounding of addend to nearest 8k */ +#define lrsel(v,a) (((v)+rnd(a))>>11) +/* rrsel with rounding of addend to nearest 8k */ +#define rrsel(v,a) ((((v)+rnd(a))&0x7ff)+((a)-rnd(a))) + +#define mask(x,sz) ((x) & ~((1<<(sz))-1)) + + +/* The reassemble_* functions prepare an immediate value for + insertion into an opcode. pa-risc uses all sorts of weird bitfields + in the instruction to hold the value. */ +static inline int sign_unext(int x, int len) +{ + int len_ones; + + len_ones = (1 << len) - 1; + return x & len_ones; +} + +static inline int low_sign_unext(int x, int len) +{ + int sign, temp; + + sign = (x >> (len-1)) & 1; + temp = sign_unext(x, len-1); + return (temp << 1) | sign; +} + +static inline int reassemble_14(int as14) +{ + return (((as14 & 0x1fff) << 1) | + ((as14 & 0x2000) >> 13)); +} + +static inline int reassemble_16a(int as16) +{ + int s, t; + + /* Unusual 16-bit encoding, for wide mode only. */ + t = (as16 << 1) & 0xffff; + s = (as16 & 0x8000); + return (t ^ s ^ (s >> 1)) | (s >> 15); +} + + +static inline int reassemble_17(int as17) +{ + return (((as17 & 0x10000) >> 16) | + ((as17 & 0x0f800) << 5) | + ((as17 & 0x00400) >> 8) | + ((as17 & 0x003ff) << 3)); +} + +static inline int reassemble_21(int as21) +{ + return (((as21 & 0x100000) >> 20) | + ((as21 & 0x0ffe00) >> 8) | + ((as21 & 0x000180) << 7) | + ((as21 & 0x00007c) << 14) | + ((as21 & 0x000003) << 12)); +} + +static inline int reassemble_22(int as22) +{ + return (((as22 & 0x200000) >> 21) | + ((as22 & 0x1f0000) << 5) | + ((as22 & 0x00f800) << 5) | + ((as22 & 0x000400) >> 8) | + ((as22 & 0x0003ff) << 3)); +} + +void *module_alloc(unsigned long size) +{ + /* using RWX means less protection for modules, but it's + * easier than trying to map the text, data, init_text and + * init_data correctly */ + return __vmalloc_node_range(size, 1, VMALLOC_START, VMALLOC_END, + GFP_KERNEL, + PAGE_KERNEL_RWX, 0, NUMA_NO_NODE, + __builtin_return_address(0)); +} + +#ifndef CONFIG_64BIT +static inline unsigned long count_gots(const Elf_Rela *rela, unsigned long n) +{ + return 0; +} + +static inline unsigned long count_fdescs(const Elf_Rela *rela, unsigned long n) +{ + return 0; +} + +static inline unsigned long count_stubs(const Elf_Rela *rela, unsigned long n) +{ + unsigned long cnt = 0; + + for (; n > 0; n--, rela++) + { + switch (ELF32_R_TYPE(rela->r_info)) { + case R_PARISC_PCREL17F: + case R_PARISC_PCREL22F: + cnt++; + } + } + + return cnt; +} +#else +static inline unsigned long count_gots(const Elf_Rela *rela, unsigned long n) +{ + unsigned long cnt = 0; + + for (; n > 0; n--, rela++) + { + switch (ELF64_R_TYPE(rela->r_info)) { + case R_PARISC_LTOFF21L: + case R_PARISC_LTOFF14R: + case R_PARISC_PCREL22F: + cnt++; + } + } + + return cnt; +} + +static inline unsigned long count_fdescs(const Elf_Rela *rela, unsigned long n) +{ + unsigned long cnt = 0; + + for (; n > 0; n--, rela++) + { + switch (ELF64_R_TYPE(rela->r_info)) { + case R_PARISC_FPTR64: + cnt++; + } + } + + return cnt; +} + +static inline unsigned long count_stubs(const Elf_Rela *rela, unsigned long n) +{ + unsigned long cnt = 0; + + for (; n > 0; n--, rela++) + { + switch (ELF64_R_TYPE(rela->r_info)) { + case R_PARISC_PCREL22F: + cnt++; + } + } + + return cnt; +} +#endif + +void module_arch_freeing_init(struct module *mod) +{ + kfree(mod->arch.section); + mod->arch.section = NULL; +} + +/* Additional bytes needed in front of individual sections */ +unsigned int arch_mod_section_prepend(struct module *mod, + unsigned int section) +{ + /* size needed for all stubs of this section (including + * one additional for correct alignment of the stubs) */ + return (mod->arch.section[section].stub_entries + 1) + * sizeof(struct stub_entry); +} + +#define CONST +int module_frob_arch_sections(CONST Elf_Ehdr *hdr, + CONST Elf_Shdr *sechdrs, + CONST char *secstrings, + struct module *me) +{ + unsigned long gots = 0, fdescs = 0, len; + unsigned int i; + struct module_memory *mod_mem; + + len = hdr->e_shnum * sizeof(me->arch.section[0]); + me->arch.section = kzalloc(len, GFP_KERNEL); + if (!me->arch.section) + return -ENOMEM; + + for (i = 1; i < hdr->e_shnum; i++) { + const Elf_Rela *rels = (void *)sechdrs[i].sh_addr; + unsigned long nrels = sechdrs[i].sh_size / sizeof(*rels); + unsigned int count, s; + + if (strncmp(secstrings + sechdrs[i].sh_name, + ".PARISC.unwind", 14) == 0) + me->arch.unwind_section = i; + + if (sechdrs[i].sh_type != SHT_RELA) + continue; + + /* some of these are not relevant for 32-bit/64-bit + * we leave them here to make the code common. the + * compiler will do its thing and optimize out the + * stuff we don't need + */ + gots += count_gots(rels, nrels); + fdescs += count_fdescs(rels, nrels); + + /* XXX: By sorting the relocs and finding duplicate entries + * we could reduce the number of necessary stubs and save + * some memory. */ + count = count_stubs(rels, nrels); + if (!count) + continue; + + /* so we need relocation stubs. reserve necessary memory. */ + /* sh_info gives the section for which we need to add stubs. */ + s = sechdrs[i].sh_info; + + /* each code section should only have one relocation section */ + WARN_ON(me->arch.section[s].stub_entries); + + /* store number of stubs we need for this section */ + me->arch.section[s].stub_entries += count; + } + + mod_mem = &me->mem[MOD_TEXT]; + /* align things a bit */ + mod_mem->size = ALIGN(mod_mem->size, 16); + me->arch.got_offset = mod_mem->size; + mod_mem->size += gots * sizeof(struct got_entry); + + mod_mem->size = ALIGN(mod_mem->size, 16); + me->arch.fdesc_offset = mod_mem->size; + mod_mem->size += fdescs * sizeof(Elf_Fdesc); + + me->arch.got_max = gots; + me->arch.fdesc_max = fdescs; + + return 0; +} + +#ifdef CONFIG_64BIT +static Elf64_Word get_got(struct module *me, unsigned long value, long addend) +{ + unsigned int i; + struct got_entry *got; + + value += addend; + + BUG_ON(value == 0); + + got = me->mem[MOD_TEXT].base + me->arch.got_offset; + for (i = 0; got[i].addr; i++) + if (got[i].addr == value) + goto out; + + BUG_ON(++me->arch.got_count > me->arch.got_max); + + got[i].addr = value; + out: + pr_debug("GOT ENTRY %d[%lx] val %lx\n", i, i*sizeof(struct got_entry), + value); + return i * sizeof(struct got_entry); +} +#endif /* CONFIG_64BIT */ + +#ifdef CONFIG_64BIT +static Elf_Addr get_fdesc(struct module *me, unsigned long value) +{ + Elf_Fdesc *fdesc = me->mem[MOD_TEXT].base + me->arch.fdesc_offset; + + if (!value) { + printk(KERN_ERR "%s: zero OPD requested!\n", me->name); + return 0; + } + + /* Look for existing fdesc entry. */ + while (fdesc->addr) { + if (fdesc->addr == value) + return (Elf_Addr)fdesc; + fdesc++; + } + + BUG_ON(++me->arch.fdesc_count > me->arch.fdesc_max); + + /* Create new one */ + fdesc->addr = value; + fdesc->gp = (Elf_Addr)me->mem[MOD_TEXT].base + me->arch.got_offset; + return (Elf_Addr)fdesc; +} +#endif /* CONFIG_64BIT */ + +enum elf_stub_type { + ELF_STUB_GOT, + ELF_STUB_MILLI, + ELF_STUB_DIRECT, +}; + +static Elf_Addr get_stub(struct module *me, unsigned long value, long addend, + enum elf_stub_type stub_type, Elf_Addr loc0, unsigned int targetsec) +{ + struct stub_entry *stub; + int __maybe_unused d; + + /* initialize stub_offset to point in front of the section */ + if (!me->arch.section[targetsec].stub_offset) { + loc0 -= (me->arch.section[targetsec].stub_entries + 1) * + sizeof(struct stub_entry); + /* get correct alignment for the stubs */ + loc0 = ALIGN(loc0, sizeof(struct stub_entry)); + me->arch.section[targetsec].stub_offset = loc0; + } + + /* get address of stub entry */ + stub = (void *) me->arch.section[targetsec].stub_offset; + me->arch.section[targetsec].stub_offset += sizeof(struct stub_entry); + + /* do not write outside available stub area */ + BUG_ON(0 == me->arch.section[targetsec].stub_entries--); + + +#ifndef CONFIG_64BIT +/* for 32-bit the stub looks like this: + * ldil L'XXX,%r1 + * be,n R'XXX(%sr4,%r1) + */ + //value = *(unsigned long *)((value + addend) & ~3); /* why? */ + + stub->insns[0] = 0x20200000; /* ldil L'XXX,%r1 */ + stub->insns[1] = 0xe0202002; /* be,n R'XXX(%sr4,%r1) */ + + stub->insns[0] |= reassemble_21(lrsel(value, addend)); + stub->insns[1] |= reassemble_17(rrsel(value, addend) / 4); + +#else +/* for 64-bit we have three kinds of stubs: + * for normal function calls: + * ldd 0(%dp),%dp + * ldd 10(%dp), %r1 + * bve (%r1) + * ldd 18(%dp), %dp + * + * for millicode: + * ldil 0, %r1 + * ldo 0(%r1), %r1 + * ldd 10(%r1), %r1 + * bve,n (%r1) + * + * for direct branches (jumps between different section of the + * same module): + * ldil 0, %r1 + * ldo 0(%r1), %r1 + * bve,n (%r1) + */ + switch (stub_type) { + case ELF_STUB_GOT: + d = get_got(me, value, addend); + if (d <= 15) { + /* Format 5 */ + stub->insns[0] = 0x0f6010db; /* ldd 0(%dp),%dp */ + stub->insns[0] |= low_sign_unext(d, 5) << 16; + } else { + /* Format 3 */ + stub->insns[0] = 0x537b0000; /* ldd 0(%dp),%dp */ + stub->insns[0] |= reassemble_16a(d); + } + stub->insns[1] = 0x53610020; /* ldd 10(%dp),%r1 */ + stub->insns[2] = 0xe820d000; /* bve (%r1) */ + stub->insns[3] = 0x537b0030; /* ldd 18(%dp),%dp */ + break; + case ELF_STUB_MILLI: + stub->insns[0] = 0x20200000; /* ldil 0,%r1 */ + stub->insns[1] = 0x34210000; /* ldo 0(%r1), %r1 */ + stub->insns[2] = 0x50210020; /* ldd 10(%r1),%r1 */ + stub->insns[3] = 0xe820d002; /* bve,n (%r1) */ + + stub->insns[0] |= reassemble_21(lrsel(value, addend)); + stub->insns[1] |= reassemble_14(rrsel(value, addend)); + break; + case ELF_STUB_DIRECT: + stub->insns[0] = 0x20200000; /* ldil 0,%r1 */ + stub->insns[1] = 0x34210000; /* ldo 0(%r1), %r1 */ + stub->insns[2] = 0xe820d002; /* bve,n (%r1) */ + + stub->insns[0] |= reassemble_21(lrsel(value, addend)); + stub->insns[1] |= reassemble_14(rrsel(value, addend)); + break; + } + +#endif + + return (Elf_Addr)stub; +} + +#ifndef CONFIG_64BIT +int apply_relocate_add(Elf_Shdr *sechdrs, + const char *strtab, + unsigned int symindex, + unsigned int relsec, + struct module *me) +{ + int i; + Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr; + Elf32_Sym *sym; + Elf32_Word *loc; + Elf32_Addr val; + Elf32_Sword addend; + Elf32_Addr dot; + Elf_Addr loc0; + unsigned int targetsec = sechdrs[relsec].sh_info; + //unsigned long dp = (unsigned long)$global$; + register unsigned long dp asm ("r27"); + + pr_debug("Applying relocate section %u to %u\n", relsec, + targetsec); + for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { + /* This is where to make the change */ + loc = (void *)sechdrs[targetsec].sh_addr + + rel[i].r_offset; + /* This is the start of the target section */ + loc0 = sechdrs[targetsec].sh_addr; + /* This is the symbol it is referring to */ + sym = (Elf32_Sym *)sechdrs[symindex].sh_addr + + ELF32_R_SYM(rel[i].r_info); + if (!sym->st_value) { + printk(KERN_WARNING "%s: Unknown symbol %s\n", + me->name, strtab + sym->st_name); + return -ENOENT; + } + //dot = (sechdrs[relsec].sh_addr + rel->r_offset) & ~0x03; + dot = (Elf32_Addr)loc & ~0x03; + + val = sym->st_value; + addend = rel[i].r_addend; + +#if 0 +#define r(t) ELF32_R_TYPE(rel[i].r_info)==t ? #t : + pr_debug("Symbol %s loc 0x%x val 0x%x addend 0x%x: %s\n", + strtab + sym->st_name, + (uint32_t)loc, val, addend, + r(R_PARISC_PLABEL32) + r(R_PARISC_DIR32) + r(R_PARISC_DIR21L) + r(R_PARISC_DIR14R) + r(R_PARISC_SEGREL32) + r(R_PARISC_DPREL21L) + r(R_PARISC_DPREL14R) + r(R_PARISC_PCREL17F) + r(R_PARISC_PCREL22F) + "UNKNOWN"); +#undef r +#endif + + switch (ELF32_R_TYPE(rel[i].r_info)) { + case R_PARISC_PLABEL32: + /* 32-bit function address */ + /* no function descriptors... */ + *loc = fsel(val, addend); + break; + case R_PARISC_DIR32: + /* direct 32-bit ref */ + *loc = fsel(val, addend); + break; + case R_PARISC_DIR21L: + /* left 21 bits of effective address */ + val = lrsel(val, addend); + *loc = mask(*loc, 21) | reassemble_21(val); + break; + case R_PARISC_DIR14R: + /* right 14 bits of effective address */ + val = rrsel(val, addend); + *loc = mask(*loc, 14) | reassemble_14(val); + break; + case R_PARISC_SEGREL32: + /* 32-bit segment relative address */ + /* See note about special handling of SEGREL32 at + * the beginning of this file. + */ + *loc = fsel(val, addend); + break; + case R_PARISC_SECREL32: + /* 32-bit section relative address. */ + *loc = fsel(val, addend); + break; + case R_PARISC_DPREL21L: + /* left 21 bit of relative address */ + val = lrsel(val - dp, addend); + *loc = mask(*loc, 21) | reassemble_21(val); + break; + case R_PARISC_DPREL14R: + /* right 14 bit of relative address */ + val = rrsel(val - dp, addend); + *loc = mask(*loc, 14) | reassemble_14(val); + break; + case R_PARISC_PCREL17F: + /* 17-bit PC relative address */ + /* calculate direct call offset */ + val += addend; + val = (val - dot - 8)/4; + if (!RELOC_REACHABLE(val, 17)) { + /* direct distance too far, create + * stub entry instead */ + val = get_stub(me, sym->st_value, addend, + ELF_STUB_DIRECT, loc0, targetsec); + val = (val - dot - 8)/4; + CHECK_RELOC(val, 17); + } + *loc = (*loc & ~0x1f1ffd) | reassemble_17(val); + break; + case R_PARISC_PCREL22F: + /* 22-bit PC relative address; only defined for pa20 */ + /* calculate direct call offset */ + val += addend; + val = (val - dot - 8)/4; + if (!RELOC_REACHABLE(val, 22)) { + /* direct distance too far, create + * stub entry instead */ + val = get_stub(me, sym->st_value, addend, + ELF_STUB_DIRECT, loc0, targetsec); + val = (val - dot - 8)/4; + CHECK_RELOC(val, 22); + } + *loc = (*loc & ~0x3ff1ffd) | reassemble_22(val); + break; + case R_PARISC_PCREL32: + /* 32-bit PC relative address */ + *loc = val - dot - 8 + addend; + break; + + default: + printk(KERN_ERR "module %s: Unknown relocation: %u\n", + me->name, ELF32_R_TYPE(rel[i].r_info)); + return -ENOEXEC; + } + } + + return 0; +} + +#else +int apply_relocate_add(Elf_Shdr *sechdrs, + const char *strtab, + unsigned int symindex, + unsigned int relsec, + struct module *me) +{ + int i; + Elf64_Rela *rel = (void *)sechdrs[relsec].sh_addr; + Elf64_Sym *sym; + Elf64_Word *loc; + Elf64_Xword *loc64; + Elf64_Addr val; + Elf64_Sxword addend; + Elf64_Addr dot; + Elf_Addr loc0; + unsigned int targetsec = sechdrs[relsec].sh_info; + + pr_debug("Applying relocate section %u to %u\n", relsec, + targetsec); + for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { + /* This is where to make the change */ + loc = (void *)sechdrs[targetsec].sh_addr + + rel[i].r_offset; + /* This is the start of the target section */ + loc0 = sechdrs[targetsec].sh_addr; + /* This is the symbol it is referring to */ + sym = (Elf64_Sym *)sechdrs[symindex].sh_addr + + ELF64_R_SYM(rel[i].r_info); + if (!sym->st_value) { + printk(KERN_WARNING "%s: Unknown symbol %s\n", + me->name, strtab + sym->st_name); + return -ENOENT; + } + //dot = (sechdrs[relsec].sh_addr + rel->r_offset) & ~0x03; + dot = (Elf64_Addr)loc & ~0x03; + loc64 = (Elf64_Xword *)loc; + + val = sym->st_value; + addend = rel[i].r_addend; + +#if 0 +#define r(t) ELF64_R_TYPE(rel[i].r_info)==t ? #t : + printk("Symbol %s loc %p val 0x%Lx addend 0x%Lx: %s\n", + strtab + sym->st_name, + loc, val, addend, + r(R_PARISC_LTOFF14R) + r(R_PARISC_LTOFF21L) + r(R_PARISC_PCREL22F) + r(R_PARISC_DIR64) + r(R_PARISC_SEGREL32) + r(R_PARISC_FPTR64) + "UNKNOWN"); +#undef r +#endif + + switch (ELF64_R_TYPE(rel[i].r_info)) { + case R_PARISC_LTOFF21L: + /* LT-relative; left 21 bits */ + val = get_got(me, val, addend); + pr_debug("LTOFF21L Symbol %s loc %p val %llx\n", + strtab + sym->st_name, + loc, val); + val = lrsel(val, 0); + *loc = mask(*loc, 21) | reassemble_21(val); + break; + case R_PARISC_LTOFF14R: + /* L(ltoff(val+addend)) */ + /* LT-relative; right 14 bits */ + val = get_got(me, val, addend); + val = rrsel(val, 0); + pr_debug("LTOFF14R Symbol %s loc %p val %llx\n", + strtab + sym->st_name, + loc, val); + *loc = mask(*loc, 14) | reassemble_14(val); + break; + case R_PARISC_PCREL22F: + /* PC-relative; 22 bits */ + pr_debug("PCREL22F Symbol %s loc %p val %llx\n", + strtab + sym->st_name, + loc, val); + val += addend; + /* can we reach it locally? */ + if (within_module(val, me)) { + /* this is the case where the symbol is local + * to the module, but in a different section, + * so stub the jump in case it's more than 22 + * bits away */ + val = (val - dot - 8)/4; + if (!RELOC_REACHABLE(val, 22)) { + /* direct distance too far, create + * stub entry instead */ + val = get_stub(me, sym->st_value, + addend, ELF_STUB_DIRECT, + loc0, targetsec); + } else { + /* Ok, we can reach it directly. */ + val = sym->st_value; + val += addend; + } + } else { + val = sym->st_value; + if (strncmp(strtab + sym->st_name, "$$", 2) + == 0) + val = get_stub(me, val, addend, ELF_STUB_MILLI, + loc0, targetsec); + else + val = get_stub(me, val, addend, ELF_STUB_GOT, + loc0, targetsec); + } + pr_debug("STUB FOR %s loc %px, val %llx+%llx at %llx\n", + strtab + sym->st_name, loc, sym->st_value, + addend, val); + val = (val - dot - 8)/4; + CHECK_RELOC(val, 22); + *loc = (*loc & ~0x3ff1ffd) | reassemble_22(val); + break; + case R_PARISC_PCREL32: + /* 32-bit PC relative address */ + *loc = val - dot - 8 + addend; + break; + case R_PARISC_PCREL64: + /* 64-bit PC relative address */ + *loc64 = val - dot - 8 + addend; + break; + case R_PARISC_DIR64: + /* 64-bit effective address */ + *loc64 = val + addend; + break; + case R_PARISC_SEGREL32: + /* 32-bit segment relative address */ + /* See note about special handling of SEGREL32 at + * the beginning of this file. + */ + *loc = fsel(val, addend); + break; + case R_PARISC_SECREL32: + /* 32-bit section relative address. */ + *loc = fsel(val, addend); + break; + case R_PARISC_FPTR64: + /* 64-bit function address */ + if (within_module(val + addend, me)) { + *loc64 = get_fdesc(me, val+addend); + pr_debug("FDESC for %s at %llx points to %llx\n", + strtab + sym->st_name, *loc64, + ((Elf_Fdesc *)*loc64)->addr); + } else { + /* if the symbol is not local to this + * module then val+addend is a pointer + * to the function descriptor */ + pr_debug("Non local FPTR64 Symbol %s loc %p val %llx\n", + strtab + sym->st_name, + loc, val); + *loc64 = val + addend; + } + break; + + default: + printk(KERN_ERR "module %s: Unknown relocation: %Lu\n", + me->name, ELF64_R_TYPE(rel[i].r_info)); + return -ENOEXEC; + } + } + return 0; +} +#endif + +static void +register_unwind_table(struct module *me, + const Elf_Shdr *sechdrs) +{ + unsigned char *table, *end; + unsigned long gp; + + if (!me->arch.unwind_section) + return; + + table = (unsigned char *)sechdrs[me->arch.unwind_section].sh_addr; + end = table + sechdrs[me->arch.unwind_section].sh_size; + gp = (Elf_Addr)me->mem[MOD_TEXT].base + me->arch.got_offset; + + pr_debug("register_unwind_table(), sect = %d at 0x%p - 0x%p (gp=0x%lx)\n", + me->arch.unwind_section, table, end, gp); + me->arch.unwind = unwind_table_add(me->name, 0, gp, table, end); +} + +static void +deregister_unwind_table(struct module *me) +{ + if (me->arch.unwind) + unwind_table_remove(me->arch.unwind); +} + +int module_finalize(const Elf_Ehdr *hdr, + const Elf_Shdr *sechdrs, + struct module *me) +{ + int i; + unsigned long nsyms; + const char *strtab = NULL; + const Elf_Shdr *s; + char *secstrings; + int symindex __maybe_unused = -1; + Elf_Sym *newptr, *oldptr; + Elf_Shdr *symhdr = NULL; +#ifdef DEBUG + Elf_Fdesc *entry; + u32 *addr; + + entry = (Elf_Fdesc *)me->init; + printk("FINALIZE, ->init FPTR is %p, GP %lx ADDR %lx\n", entry, + entry->gp, entry->addr); + addr = (u32 *)entry->addr; + printk("INSNS: %x %x %x %x\n", + addr[0], addr[1], addr[2], addr[3]); + printk("got entries used %ld, gots max %ld\n" + "fdescs used %ld, fdescs max %ld\n", + me->arch.got_count, me->arch.got_max, + me->arch.fdesc_count, me->arch.fdesc_max); +#endif + + register_unwind_table(me, sechdrs); + + /* haven't filled in me->symtab yet, so have to find it + * ourselves */ + for (i = 1; i < hdr->e_shnum; i++) { + if(sechdrs[i].sh_type == SHT_SYMTAB + && (sechdrs[i].sh_flags & SHF_ALLOC)) { + int strindex = sechdrs[i].sh_link; + symindex = i; + /* FIXME: AWFUL HACK + * The cast is to drop the const from + * the sechdrs pointer */ + symhdr = (Elf_Shdr *)&sechdrs[i]; + strtab = (char *)sechdrs[strindex].sh_addr; + break; + } + } + + pr_debug("module %s: strtab %p, symhdr %p\n", + me->name, strtab, symhdr); + + if(me->arch.got_count > MAX_GOTS) { + printk(KERN_ERR "%s: Global Offset Table overflow (used %ld, allowed %d)\n", + me->name, me->arch.got_count, MAX_GOTS); + return -EINVAL; + } + + kfree(me->arch.section); + me->arch.section = NULL; + + /* no symbol table */ + if(symhdr == NULL) + return 0; + + oldptr = (void *)symhdr->sh_addr; + newptr = oldptr + 1; /* we start counting at 1 */ + nsyms = symhdr->sh_size / sizeof(Elf_Sym); + pr_debug("OLD num_symtab %lu\n", nsyms); + + for (i = 1; i < nsyms; i++) { + oldptr++; /* note, count starts at 1 so preincrement */ + if(strncmp(strtab + oldptr->st_name, + ".L", 2) == 0) + continue; + + if(newptr != oldptr) + *newptr++ = *oldptr; + else + newptr++; + + } + nsyms = newptr - (Elf_Sym *)symhdr->sh_addr; + pr_debug("NEW num_symtab %lu\n", nsyms); + symhdr->sh_size = nsyms * sizeof(Elf_Sym); + + /* find .altinstructions section */ + secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset; + for (s = sechdrs; s < sechdrs + hdr->e_shnum; s++) { + void *aseg = (void *) s->sh_addr; + char *secname = secstrings + s->sh_name; + + if (!strcmp(".altinstructions", secname)) + /* patch .altinstructions */ + apply_alternatives(aseg, aseg + s->sh_size, me->name); + +#ifdef CONFIG_DYNAMIC_FTRACE + /* For 32 bit kernels we're compiling modules with + * -ffunction-sections so we must relocate the addresses in the + * ftrace callsite section. + */ + if (symindex != -1 && !strcmp(secname, FTRACE_CALLSITE_SECTION)) { + int err; + if (s->sh_type == SHT_REL) + err = apply_relocate((Elf_Shdr *)sechdrs, + strtab, symindex, + s - sechdrs, me); + else if (s->sh_type == SHT_RELA) + err = apply_relocate_add((Elf_Shdr *)sechdrs, + strtab, symindex, + s - sechdrs, me); + if (err) + return err; + } +#endif + } + return 0; +} + +void module_arch_cleanup(struct module *mod) +{ + deregister_unwind_table(mod); +} + +#ifdef CONFIG_64BIT +void *dereference_module_function_descriptor(struct module *mod, void *ptr) +{ + unsigned long start_opd = (Elf64_Addr)mod->mem[MOD_TEXT].base + + mod->arch.fdesc_offset; + unsigned long end_opd = start_opd + + mod->arch.fdesc_count * sizeof(Elf64_Fdesc); + + if (ptr < (void *)start_opd || ptr >= (void *)end_opd) + return ptr; + + return dereference_function_descriptor(ptr); +} +#endif |