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commit e5f6d9afa3415104e402cd69288bb03f7165eeba
parent c300af28572d05ae6891c359a7c8c2c81f01dccf
Author: Linus Torvalds <torvalds@linux-foundation.org>
Date:   Thu, 25 Oct 2018 18:14:31 -0700

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc

Pull sparc fix from David Miller:
 "Build regression fix"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc: Fix VDSO build with older binutils.

Diffstat:
March/sparc/include/asm/vdso.h | 2--
March/sparc/vdso/vclock_gettime.c | 149++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-----------
March/sparc/vdso/vdso-layout.lds.S | 3---
March/sparc/vdso/vdso.lds.S | 2++
March/sparc/vdso/vdso2c.h | 17+----------------
March/sparc/vdso/vdso32/vdso32.lds.S | 2++
March/sparc/vdso/vma.c | 222+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++--------
7 files changed, 335 insertions(+), 62 deletions(-)

diff --git a/arch/sparc/include/asm/vdso.h b/arch/sparc/include/asm/vdso.h @@ -9,8 +9,6 @@ struct vdso_image { void *data; unsigned long size; /* Always a multiple of PAGE_SIZE */ - unsigned long tick_patch, tick_patch_len; - long sym_vvar_start; /* Negative offset to the vvar area */ }; diff --git a/arch/sparc/vdso/vclock_gettime.c b/arch/sparc/vdso/vclock_gettime.c @@ -90,16 +90,15 @@ notrace static __always_inline u64 vread_tick(void) { u64 ret; - __asm__ __volatile__("1:\n\t" - "rd %%tick, %0\n\t" - ".pushsection .tick_patch, \"a\"\n\t" - ".word 1b - ., 1f - .\n\t" - ".popsection\n\t" - ".pushsection .tick_patch_replacement, \"ax\"\n\t" - "1:\n\t" - "rd %%asr24, %0\n\t" - ".popsection\n" - : "=r" (ret)); + __asm__ __volatile__("rd %%tick, %0" : "=r" (ret)); + return ret; +} + +notrace static __always_inline u64 vread_tick_stick(void) +{ + u64 ret; + + __asm__ __volatile__("rd %%asr24, %0" : "=r" (ret)); return ret; } #else @@ -107,16 +106,18 @@ notrace static __always_inline u64 vread_tick(void) { register unsigned long long ret asm("o4"); - __asm__ __volatile__("1:\n\t" - "rd %%tick, %L0\n\t" - "srlx %L0, 32, %H0\n\t" - ".pushsection .tick_patch, \"a\"\n\t" - ".word 1b - ., 1f - .\n\t" - ".popsection\n\t" - ".pushsection .tick_patch_replacement, \"ax\"\n\t" - "1:\n\t" - "rd %%asr24, %L0\n\t" - ".popsection\n" + __asm__ __volatile__("rd %%tick, %L0\n\t" + "srlx %L0, 32, %H0" + : "=r" (ret)); + return ret; +} + +notrace static __always_inline u64 vread_tick_stick(void) +{ + register unsigned long long ret asm("o4"); + + __asm__ __volatile__("rd %%asr24, %L0\n\t" + "srlx %L0, 32, %H0" : "=r" (ret)); return ret; } @@ -132,6 +133,16 @@ notrace static __always_inline u64 vgetsns(struct vvar_data *vvar) return v * vvar->clock.mult; } +notrace static __always_inline u64 vgetsns_stick(struct vvar_data *vvar) +{ + u64 v; + u64 cycles; + + cycles = vread_tick_stick(); + v = (cycles - vvar->clock.cycle_last) & vvar->clock.mask; + return v * vvar->clock.mult; +} + notrace static __always_inline int do_realtime(struct vvar_data *vvar, struct timespec *ts) { @@ -152,6 +163,26 @@ notrace static __always_inline int do_realtime(struct vvar_data *vvar, return 0; } +notrace static __always_inline int do_realtime_stick(struct vvar_data *vvar, + struct timespec *ts) +{ + unsigned long seq; + u64 ns; + + do { + seq = vvar_read_begin(vvar); + ts->tv_sec = vvar->wall_time_sec; + ns = vvar->wall_time_snsec; + ns += vgetsns_stick(vvar); + ns >>= vvar->clock.shift; + } while (unlikely(vvar_read_retry(vvar, seq))); + + ts->tv_sec += __iter_div_u64_rem(ns, NSEC_PER_SEC, &ns); + ts->tv_nsec = ns; + + return 0; +} + notrace static __always_inline int do_monotonic(struct vvar_data *vvar, struct timespec *ts) { @@ -172,6 +203,26 @@ notrace static __always_inline int do_monotonic(struct vvar_data *vvar, return 0; } +notrace static __always_inline int do_monotonic_stick(struct vvar_data *vvar, + struct timespec *ts) +{ + unsigned long seq; + u64 ns; + + do { + seq = vvar_read_begin(vvar); + ts->tv_sec = vvar->monotonic_time_sec; + ns = vvar->monotonic_time_snsec; + ns += vgetsns_stick(vvar); + ns >>= vvar->clock.shift; + } while (unlikely(vvar_read_retry(vvar, seq))); + + ts->tv_sec += __iter_div_u64_rem(ns, NSEC_PER_SEC, &ns); + ts->tv_nsec = ns; + + return 0; +} + notrace static int do_realtime_coarse(struct vvar_data *vvar, struct timespec *ts) { @@ -228,6 +279,31 @@ clock_gettime(clockid_t, struct timespec *) __attribute__((weak, alias("__vdso_clock_gettime"))); notrace int +__vdso_clock_gettime_stick(clockid_t clock, struct timespec *ts) +{ + struct vvar_data *vvd = get_vvar_data(); + + switch (clock) { + case CLOCK_REALTIME: + if (unlikely(vvd->vclock_mode == VCLOCK_NONE)) + break; + return do_realtime_stick(vvd, ts); + case CLOCK_MONOTONIC: + if (unlikely(vvd->vclock_mode == VCLOCK_NONE)) + break; + return do_monotonic_stick(vvd, ts); + case CLOCK_REALTIME_COARSE: + return do_realtime_coarse(vvd, ts); + case CLOCK_MONOTONIC_COARSE: + return do_monotonic_coarse(vvd, ts); + } + /* + * Unknown clock ID ? Fall back to the syscall. + */ + return vdso_fallback_gettime(clock, ts); +} + +notrace int __vdso_gettimeofday(struct timeval *tv, struct timezone *tz) { struct vvar_data *vvd = get_vvar_data(); @@ -262,3 +338,36 @@ __vdso_gettimeofday(struct timeval *tv, struct timezone *tz) int gettimeofday(struct timeval *, struct timezone *) __attribute__((weak, alias("__vdso_gettimeofday"))); + +notrace int +__vdso_gettimeofday_stick(struct timeval *tv, struct timezone *tz) +{ + struct vvar_data *vvd = get_vvar_data(); + + if (likely(vvd->vclock_mode != VCLOCK_NONE)) { + if (likely(tv != NULL)) { + union tstv_t { + struct timespec ts; + struct timeval tv; + } *tstv = (union tstv_t *) tv; + do_realtime_stick(vvd, &tstv->ts); + /* + * Assign before dividing to ensure that the division is + * done in the type of tv_usec, not tv_nsec. + * + * There cannot be > 1 billion usec in a second: + * do_realtime() has already distributed such overflow + * into tv_sec. So we can assign it to an int safely. + */ + tstv->tv.tv_usec = tstv->ts.tv_nsec; + tstv->tv.tv_usec /= 1000; + } + if (unlikely(tz != NULL)) { + /* Avoid memcpy. Some old compilers fail to inline it */ + tz->tz_minuteswest = vvd->tz_minuteswest; + tz->tz_dsttime = vvd->tz_dsttime; + } + return 0; + } + return vdso_fallback_gettimeofday(tv, tz); +} diff --git a/arch/sparc/vdso/vdso-layout.lds.S b/arch/sparc/vdso/vdso-layout.lds.S @@ -73,9 +73,6 @@ SECTIONS .text : { *(.text*) } :text =0x90909090, - .tick_patch : { *(.tick_patch) } :text - .tick_patch_insns : { *(.tick_patch_insns) } :text - /DISCARD/ : { *(.discard) *(.discard.*) diff --git a/arch/sparc/vdso/vdso.lds.S b/arch/sparc/vdso/vdso.lds.S @@ -18,8 +18,10 @@ VERSION { global: clock_gettime; __vdso_clock_gettime; + __vdso_clock_gettime_stick; gettimeofday; __vdso_gettimeofday; + __vdso_gettimeofday_stick; local: *; }; } diff --git a/arch/sparc/vdso/vdso2c.h b/arch/sparc/vdso/vdso2c.h @@ -17,11 +17,9 @@ static void BITSFUNC(go)(void *raw_addr, size_t raw_len, unsigned long mapping_size; int i; unsigned long j; - ELF(Shdr) *symtab_hdr = NULL, *strtab_hdr, *secstrings_hdr, - *patch_sec = NULL; + ELF(Shdr) *symtab_hdr = NULL, *strtab_hdr; ELF(Ehdr) *hdr = (ELF(Ehdr) *)raw_addr; ELF(Dyn) *dyn = 0, *dyn_end = 0; - const char *secstrings; INT_BITS syms[NSYMS] = {}; ELF(Phdr) *pt = (ELF(Phdr) *)(raw_addr + GET_BE(&hdr->e_phoff)); @@ -64,18 +62,11 @@ static void BITSFUNC(go)(void *raw_addr, size_t raw_len, } /* Walk the section table */ - secstrings_hdr = raw_addr + GET_BE(&hdr->e_shoff) + - GET_BE(&hdr->e_shentsize)*GET_BE(&hdr->e_shstrndx); - secstrings = raw_addr + GET_BE(&secstrings_hdr->sh_offset); for (i = 0; i < GET_BE(&hdr->e_shnum); i++) { ELF(Shdr) *sh = raw_addr + GET_BE(&hdr->e_shoff) + GET_BE(&hdr->e_shentsize) * i; if (GET_BE(&sh->sh_type) == SHT_SYMTAB) symtab_hdr = sh; - - if (!strcmp(secstrings + GET_BE(&sh->sh_name), - ".tick_patch")) - patch_sec = sh; } if (!symtab_hdr) @@ -142,12 +133,6 @@ static void BITSFUNC(go)(void *raw_addr, size_t raw_len, fprintf(outfile, "const struct vdso_image %s_builtin = {\n", name); fprintf(outfile, "\t.data = raw_data,\n"); fprintf(outfile, "\t.size = %lu,\n", mapping_size); - if (patch_sec) { - fprintf(outfile, "\t.tick_patch = %lu,\n", - (unsigned long)GET_BE(&patch_sec->sh_offset)); - fprintf(outfile, "\t.tick_patch_len = %lu,\n", - (unsigned long)GET_BE(&patch_sec->sh_size)); - } for (i = 0; i < NSYMS; i++) { if (required_syms[i].export && syms[i]) fprintf(outfile, "\t.sym_%s = %" PRIi64 ",\n", diff --git a/arch/sparc/vdso/vdso32/vdso32.lds.S b/arch/sparc/vdso/vdso32/vdso32.lds.S @@ -17,8 +17,10 @@ VERSION { global: clock_gettime; __vdso_clock_gettime; + __vdso_clock_gettime_stick; gettimeofday; __vdso_gettimeofday; + __vdso_gettimeofday_stick; local: *; }; } diff --git a/arch/sparc/vdso/vma.c b/arch/sparc/vdso/vma.c @@ -42,24 +42,201 @@ static struct vm_special_mapping vdso_mapping32 = { struct vvar_data *vvar_data; -struct tick_patch_entry { - s32 orig, repl; +struct vdso_elfinfo32 { + Elf32_Ehdr *hdr; + Elf32_Sym *dynsym; + unsigned long dynsymsize; + const char *dynstr; + unsigned long text; }; -static void stick_patch(const struct vdso_image *image) +struct vdso_elfinfo64 { + Elf64_Ehdr *hdr; + Elf64_Sym *dynsym; + unsigned long dynsymsize; + const char *dynstr; + unsigned long text; +}; + +struct vdso_elfinfo { + union { + struct vdso_elfinfo32 elf32; + struct vdso_elfinfo64 elf64; + } u; +}; + +static void *one_section64(struct vdso_elfinfo64 *e, const char *name, + unsigned long *size) +{ + const char *snames; + Elf64_Shdr *shdrs; + unsigned int i; + + shdrs = (void *)e->hdr + e->hdr->e_shoff; + snames = (void *)e->hdr + shdrs[e->hdr->e_shstrndx].sh_offset; + for (i = 1; i < e->hdr->e_shnum; i++) { + if (!strcmp(snames+shdrs[i].sh_name, name)) { + if (size) + *size = shdrs[i].sh_size; + return (void *)e->hdr + shdrs[i].sh_offset; + } + } + return NULL; +} + +static int find_sections64(const struct vdso_image *image, struct vdso_elfinfo *_e) +{ + struct vdso_elfinfo64 *e = &_e->u.elf64; + + e->hdr = image->data; + e->dynsym = one_section64(e, ".dynsym", &e->dynsymsize); + e->dynstr = one_section64(e, ".dynstr", NULL); + + if (!e->dynsym || !e->dynstr) { + pr_err("VDSO64: Missing symbol sections.\n"); + return -ENODEV; + } + return 0; +} + +static Elf64_Sym *find_sym64(const struct vdso_elfinfo64 *e, const char *name) +{ + unsigned int i; + + for (i = 0; i < (e->dynsymsize / sizeof(Elf64_Sym)); i++) { + Elf64_Sym *s = &e->dynsym[i]; + if (s->st_name == 0) + continue; + if (!strcmp(e->dynstr + s->st_name, name)) + return s; + } + return NULL; +} + +static int patchsym64(struct vdso_elfinfo *_e, const char *orig, + const char *new) +{ + struct vdso_elfinfo64 *e = &_e->u.elf64; + Elf64_Sym *osym = find_sym64(e, orig); + Elf64_Sym *nsym = find_sym64(e, new); + + if (!nsym || !osym) { + pr_err("VDSO64: Missing symbols.\n"); + return -ENODEV; + } + osym->st_value = nsym->st_value; + osym->st_size = nsym->st_size; + osym->st_info = nsym->st_info; + osym->st_other = nsym->st_other; + osym->st_shndx = nsym->st_shndx; + + return 0; +} + +static void *one_section32(struct vdso_elfinfo32 *e, const char *name, + unsigned long *size) +{ + const char *snames; + Elf32_Shdr *shdrs; + unsigned int i; + + shdrs = (void *)e->hdr + e->hdr->e_shoff; + snames = (void *)e->hdr + shdrs[e->hdr->e_shstrndx].sh_offset; + for (i = 1; i < e->hdr->e_shnum; i++) { + if (!strcmp(snames+shdrs[i].sh_name, name)) { + if (size) + *size = shdrs[i].sh_size; + return (void *)e->hdr + shdrs[i].sh_offset; + } + } + return NULL; +} + +static int find_sections32(const struct vdso_image *image, struct vdso_elfinfo *_e) +{ + struct vdso_elfinfo32 *e = &_e->u.elf32; + + e->hdr = image->data; + e->dynsym = one_section32(e, ".dynsym", &e->dynsymsize); + e->dynstr = one_section32(e, ".dynstr", NULL); + + if (!e->dynsym || !e->dynstr) { + pr_err("VDSO32: Missing symbol sections.\n"); + return -ENODEV; + } + return 0; +} + +static Elf32_Sym *find_sym32(const struct vdso_elfinfo32 *e, const char *name) { - struct tick_patch_entry *p, *p_end; + unsigned int i; + + for (i = 0; i < (e->dynsymsize / sizeof(Elf32_Sym)); i++) { + Elf32_Sym *s = &e->dynsym[i]; + if (s->st_name == 0) + continue; + if (!strcmp(e->dynstr + s->st_name, name)) + return s; + } + return NULL; +} - p = image->data + image->tick_patch; - p_end = (void *)p + image->tick_patch_len; - while (p < p_end) { - u32 *instr = (void *)&p->orig + p->orig; - u32 *repl = (void *)&p->repl + p->repl; +static int patchsym32(struct vdso_elfinfo *_e, const char *orig, + const char *new) +{ + struct vdso_elfinfo32 *e = &_e->u.elf32; + Elf32_Sym *osym = find_sym32(e, orig); + Elf32_Sym *nsym = find_sym32(e, new); - *instr = *repl; - flushi(instr); - p++; + if (!nsym || !osym) { + pr_err("VDSO32: Missing symbols.\n"); + return -ENODEV; } + osym->st_value = nsym->st_value; + osym->st_size = nsym->st_size; + osym->st_info = nsym->st_info; + osym->st_other = nsym->st_other; + osym->st_shndx = nsym->st_shndx; + + return 0; +} + +static int find_sections(const struct vdso_image *image, struct vdso_elfinfo *e, + bool elf64) +{ + if (elf64) + return find_sections64(image, e); + else + return find_sections32(image, e); +} + +static int patch_one_symbol(struct vdso_elfinfo *e, const char *orig, + const char *new_target, bool elf64) +{ + if (elf64) + return patchsym64(e, orig, new_target); + else + return patchsym32(e, orig, new_target); +} + +static int stick_patch(const struct vdso_image *image, struct vdso_elfinfo *e, bool elf64) +{ + int err; + + err = find_sections(image, e, elf64); + if (err) + return err; + + err = patch_one_symbol(e, + "__vdso_gettimeofday", + "__vdso_gettimeofday_stick", elf64); + if (err) + return err; + + return patch_one_symbol(e, + "__vdso_clock_gettime", + "__vdso_clock_gettime_stick", elf64); + return 0; } /* @@ -67,13 +244,19 @@ static void stick_patch(const struct vdso_image *image) * kernel image. */ int __init init_vdso_image(const struct vdso_image *image, - struct vm_special_mapping *vdso_mapping) + struct vm_special_mapping *vdso_mapping, bool elf64) { - int i; + int cnpages = (image->size) / PAGE_SIZE; struct page *dp, **dpp = NULL; - int dnpages = 0; struct page *cp, **cpp = NULL; - int cnpages = (image->size) / PAGE_SIZE; + struct vdso_elfinfo ei; + int i, dnpages = 0; + + if (tlb_type != spitfire) { + int err = stick_patch(image, &ei, elf64); + if (err) + return err; + } /* * First, the vdso text. This is initialied data, an integral number of @@ -88,9 +271,6 @@ int __init init_vdso_image(const struct vdso_image *image, if (!cpp) goto oom; - if (tlb_type != spitfire) - stick_patch(image); - for (i = 0; i < cnpages; i++) { cp = alloc_page(GFP_KERNEL); if (!cp) @@ -153,13 +333,13 @@ static int __init init_vdso(void) { int err = 0; #ifdef CONFIG_SPARC64 - err = init_vdso_image(&vdso_image_64_builtin, &vdso_mapping64); + err = init_vdso_image(&vdso_image_64_builtin, &vdso_mapping64, true); if (err) return err; #endif #ifdef CONFIG_COMPAT - err = init_vdso_image(&vdso_image_32_builtin, &vdso_mapping32); + err = init_vdso_image(&vdso_image_32_builtin, &vdso_mapping32, false); #endif return err;