diff options
Diffstat (limited to 'elf')
| -rw-r--r-- | elf/Makefile | 2 | ||||
| -rw-r--r-- | elf/dl-hwcaps.c | 279 | ||||
| -rw-r--r-- | elf/dl-support.c | 17 | ||||
| -rw-r--r-- | elf/dl-sysdep.c | 254 |
4 files changed, 280 insertions, 272 deletions
diff --git a/elf/Makefile b/elf/Makefile index 58cc15c3f1..e91c3b428d 100644 --- a/elf/Makefile +++ b/elf/Makefile @@ -28,7 +28,7 @@ routines = $(dl-routines) dl-support dl-iteratephdr \ # The core dynamic linking functions are in libc for the static and # profiled libraries. -dl-routines = $(addprefix dl-,load lookup object reloc deps \ +dl-routines = $(addprefix dl-,load lookup object reloc deps hwcaps \ runtime error init fini debug misc \ version profile conflict tls origin scope \ execstack caller open close trampoline) diff --git a/elf/dl-hwcaps.c b/elf/dl-hwcaps.c new file mode 100644 index 0000000000..d911548f2a --- /dev/null +++ b/elf/dl-hwcaps.c @@ -0,0 +1,279 @@ +/* Hardware capability support for run-time dynamic loader. + Copyright (C) 2012 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <http://www.gnu.org/licenses/>. */ + +#include <assert.h> +#include <elf.h> +#include <errno.h> +#include <libintl.h> +#include <unistd.h> +#include <ldsodefs.h> + +#include <dl-procinfo.h> + +#ifdef _DL_FIRST_PLATFORM +# define _DL_FIRST_EXTRA (_DL_FIRST_PLATFORM + _DL_PLATFORMS_COUNT) +#else +# define _DL_FIRST_EXTRA _DL_HWCAP_COUNT +#endif + +/* Return an array of useful/necessary hardware capability names. */ +const struct r_strlenpair * +internal_function +_dl_important_hwcaps (const char *platform, size_t platform_len, size_t *sz, + size_t *max_capstrlen) +{ + /* Determine how many important bits are set. */ + uint64_t masked = GLRO(dl_hwcap) & GLRO(dl_hwcap_mask); + size_t cnt = platform != NULL; + size_t n, m; + size_t total; + struct r_strlenpair *temp; + struct r_strlenpair *result; + struct r_strlenpair *rp; + char *cp; + + /* Count the number of bits set in the masked value. */ + for (n = 0; (~((1ULL << n) - 1) & masked) != 0; ++n) + if ((masked & (1ULL << n)) != 0) + ++cnt; + +#if defined NEED_DL_SYSINFO || defined NEED_DL_SYSINFO_DSO + /* The system-supplied DSO can contain a note of type 2, vendor "GNU". + This gives us a list of names to treat as fake hwcap bits. */ + + const char *dsocaps = NULL; + size_t dsocapslen = 0; + if (GLRO(dl_sysinfo_map) != NULL) + { + const ElfW(Phdr) *const phdr = GLRO(dl_sysinfo_map)->l_phdr; + const ElfW(Word) phnum = GLRO(dl_sysinfo_map)->l_phnum; + for (uint_fast16_t i = 0; i < phnum; ++i) + if (phdr[i].p_type == PT_NOTE) + { + const ElfW(Addr) start = (phdr[i].p_vaddr + + GLRO(dl_sysinfo_map)->l_addr); + const struct + { + ElfW(Word) vendorlen; + ElfW(Word) datalen; + ElfW(Word) type; + } *note = (const void *) start; + while ((ElfW(Addr)) (note + 1) - start < phdr[i].p_memsz) + { +#define ROUND(len) (((len) + sizeof (ElfW(Word)) - 1) & -sizeof (ElfW(Word))) + if (note->type == NT_GNU_HWCAP + && note->vendorlen == sizeof "GNU" + && !memcmp ((note + 1), "GNU", sizeof "GNU") + && note->datalen > 2 * sizeof (ElfW(Word)) + 2) + { + const ElfW(Word) *p = ((const void *) (note + 1) + + ROUND (sizeof "GNU")); + cnt += *p++; + ++p; /* Skip mask word. */ + dsocaps = (const char *) p; + dsocapslen = note->datalen - sizeof *p * 2; + break; + } + note = ((const void *) (note + 1) + + ROUND (note->vendorlen) + ROUND (note->datalen)); +#undef ROUND + } + if (dsocaps != NULL) + break; + } + } +#endif + + /* For TLS enabled builds always add 'tls'. */ + ++cnt; + + /* Create temporary data structure to generate result table. */ + temp = (struct r_strlenpair *) alloca (cnt * sizeof (*temp)); + m = 0; +#if defined NEED_DL_SYSINFO || defined NEED_DL_SYSINFO_DSO + if (dsocaps != NULL) + { + const ElfW(Word) mask = ((const ElfW(Word) *) dsocaps)[-1]; + GLRO(dl_hwcap) |= (uint64_t) mask << _DL_FIRST_EXTRA; + /* Note that we add the dsocaps to the set already chosen by the + LD_HWCAP_MASK environment variable (or default HWCAP_IMPORTANT). + So there is no way to request ignoring an OS-supplied dsocap + string and bit like you can ignore an OS-supplied HWCAP bit. */ + GLRO(dl_hwcap_mask) |= (uint64_t) mask << _DL_FIRST_EXTRA; + size_t len; + for (const char *p = dsocaps; p < dsocaps + dsocapslen; p += len + 1) + { + uint_fast8_t bit = *p++; + len = strlen (p); + + /* Skip entries that are not enabled in the mask word. */ + if (__builtin_expect (mask & ((ElfW(Word)) 1 << bit), 1)) + { + temp[m].str = p; + temp[m].len = len; + ++m; + } + else + --cnt; + } + } +#endif + for (n = 0; masked != 0; ++n) + if ((masked & (1ULL << n)) != 0) + { + temp[m].str = _dl_hwcap_string (n); + temp[m].len = strlen (temp[m].str); + masked ^= 1ULL << n; + ++m; + } + if (platform != NULL) + { + temp[m].str = platform; + temp[m].len = platform_len; + ++m; + } + + temp[m].str = "tls"; + temp[m].len = 3; + ++m; + + assert (m == cnt); + + /* Determine the total size of all strings together. */ + if (cnt == 1) + total = temp[0].len + 1; + else + { + total = temp[0].len + temp[cnt - 1].len + 2; + if (cnt > 2) + { + total <<= 1; + for (n = 1; n + 1 < cnt; ++n) + total += temp[n].len + 1; + if (cnt > 3 + && (cnt >= sizeof (size_t) * 8 + || total + (sizeof (*result) << 3) + >= (1UL << (sizeof (size_t) * 8 - cnt + 3)))) + _dl_signal_error (ENOMEM, NULL, NULL, + N_("cannot create capability list")); + + total <<= cnt - 3; + } + } + + /* The result structure: we use a very compressed way to store the + various combinations of capability names. */ + *sz = 1 << cnt; + result = (struct r_strlenpair *) malloc (*sz * sizeof (*result) + total); + if (result == NULL) + _dl_signal_error (ENOMEM, NULL, NULL, + N_("cannot create capability list")); + + if (cnt == 1) + { + result[0].str = (char *) (result + *sz); + result[0].len = temp[0].len + 1; + result[1].str = (char *) (result + *sz); + result[1].len = 0; + cp = __mempcpy ((char *) (result + *sz), temp[0].str, temp[0].len); + *cp = '/'; + *sz = 2; + *max_capstrlen = result[0].len; + + return result; + } + + /* Fill in the information. This follows the following scheme + (indeces from TEMP for four strings): + entry #0: 0, 1, 2, 3 binary: 1111 + #1: 0, 1, 3 1101 + #2: 0, 2, 3 1011 + #3: 0, 3 1001 + This allows the representation of all possible combinations of + capability names in the string. First generate the strings. */ + result[1].str = result[0].str = cp = (char *) (result + *sz); +#define add(idx) \ + cp = __mempcpy (__mempcpy (cp, temp[idx].str, temp[idx].len), "/", 1); + if (cnt == 2) + { + add (1); + add (0); + } + else + { + n = 1 << (cnt - 1); + do + { + n -= 2; + + /* We always add the last string. */ + add (cnt - 1); + + /* Add the strings which have the bit set in N. */ + for (m = cnt - 2; m > 0; --m) + if ((n & (1 << m)) != 0) + add (m); + + /* Always add the first string. */ + add (0); + } + while (n != 0); + } +#undef add + + /* Now we are ready to install the string pointers and length. */ + for (n = 0; n < (1UL << cnt); ++n) + result[n].len = 0; + n = cnt; + do + { + size_t mask = 1 << --n; + + rp = result; + for (m = 1 << cnt; m > 0; ++rp) + if ((--m & mask) != 0) + rp->len += temp[n].len + 1; + } + while (n != 0); + + /* The first half of the strings all include the first string. */ + n = (1 << cnt) - 2; + rp = &result[2]; + while (n != (1UL << (cnt - 1))) + { + if ((--n & 1) != 0) + rp[0].str = rp[-2].str + rp[-2].len; + else + rp[0].str = rp[-1].str; + ++rp; + } + + /* The second half starts right after the first part of the string of + the corresponding entry in the first half. */ + do + { + rp[0].str = rp[-(1 << (cnt - 1))].str + temp[cnt - 1].len + 1; + ++rp; + } + while (--n != 0); + + /* The maximum string length. */ + *max_capstrlen = result[0].len; + + return result; +} diff --git a/elf/dl-support.c b/elf/dl-support.c index 424ca6ddea..fd72c1b2ad 100644 --- a/elf/dl-support.c +++ b/elf/dl-support.c @@ -335,23 +335,6 @@ _dl_non_dynamic_init (void) } } - -const struct r_strlenpair * -internal_function -_dl_important_hwcaps (const char *platform, size_t platform_len, size_t *sz, - size_t *max_capstrlen) -{ - static struct r_strlenpair result; - static char buf[1]; - - result.str = buf; /* Does not really matter. */ - result.len = 0; - - *sz = 1; - return &result; -} - - #ifdef DL_SYSINFO_IMPLEMENTATION DL_SYSINFO_IMPLEMENTATION #endif diff --git a/elf/dl-sysdep.c b/elf/dl-sysdep.c index fb0849a543..65a90469c6 100644 --- a/elf/dl-sysdep.c +++ b/elf/dl-sysdep.c @@ -44,12 +44,6 @@ #include <hp-timing.h> #include <tls.h> -#ifdef _DL_FIRST_PLATFORM -# define _DL_FIRST_EXTRA (_DL_FIRST_PLATFORM + _DL_PLATFORMS_COUNT) -#else -# define _DL_FIRST_EXTRA _DL_HWCAP_COUNT -#endif - extern char **_environ attribute_hidden; extern char _end[] attribute_hidden; @@ -350,252 +344,4 @@ _dl_show_auxv (void) } } - -/* Return an array of useful/necessary hardware capability names. */ -const struct r_strlenpair * -internal_function -_dl_important_hwcaps (const char *platform, size_t platform_len, size_t *sz, - size_t *max_capstrlen) -{ - /* Determine how many important bits are set. */ - uint64_t masked = GLRO(dl_hwcap) & GLRO(dl_hwcap_mask); - size_t cnt = platform != NULL; - size_t n, m; - size_t total; - struct r_strlenpair *temp; - struct r_strlenpair *result; - struct r_strlenpair *rp; - char *cp; - - /* Count the number of bits set in the masked value. */ - for (n = 0; (~((1ULL << n) - 1) & masked) != 0; ++n) - if ((masked & (1ULL << n)) != 0) - ++cnt; - -#if (defined NEED_DL_SYSINFO || defined NEED_DL_SYSINFO_DSO) && defined SHARED - /* The system-supplied DSO can contain a note of type 2, vendor "GNU". - This gives us a list of names to treat as fake hwcap bits. */ - - const char *dsocaps = NULL; - size_t dsocapslen = 0; - if (GLRO(dl_sysinfo_map) != NULL) - { - const ElfW(Phdr) *const phdr = GLRO(dl_sysinfo_map)->l_phdr; - const ElfW(Word) phnum = GLRO(dl_sysinfo_map)->l_phnum; - for (uint_fast16_t i = 0; i < phnum; ++i) - if (phdr[i].p_type == PT_NOTE) - { - const ElfW(Addr) start = (phdr[i].p_vaddr - + GLRO(dl_sysinfo_map)->l_addr); - const struct - { - ElfW(Word) vendorlen; - ElfW(Word) datalen; - ElfW(Word) type; - } *note = (const void *) start; - while ((ElfW(Addr)) (note + 1) - start < phdr[i].p_memsz) - { -#define ROUND(len) (((len) + sizeof (ElfW(Word)) - 1) & -sizeof (ElfW(Word))) - if (note->type == NT_GNU_HWCAP - && note->vendorlen == sizeof "GNU" - && !memcmp ((note + 1), "GNU", sizeof "GNU") - && note->datalen > 2 * sizeof (ElfW(Word)) + 2) - { - const ElfW(Word) *p = ((const void *) (note + 1) - + ROUND (sizeof "GNU")); - cnt += *p++; - ++p; /* Skip mask word. */ - dsocaps = (const char *) p; - dsocapslen = note->datalen - sizeof *p * 2; - break; - } - note = ((const void *) (note + 1) - + ROUND (note->vendorlen) + ROUND (note->datalen)); -#undef ROUND - } - if (dsocaps != NULL) - break; - } - } -#endif - - /* For TLS enabled builds always add 'tls'. */ - ++cnt; - - /* Create temporary data structure to generate result table. */ - temp = (struct r_strlenpair *) alloca (cnt * sizeof (*temp)); - m = 0; -#if (defined NEED_DL_SYSINFO || defined NEED_DL_SYSINFO_DSO) && defined SHARED - if (dsocaps != NULL) - { - const ElfW(Word) mask = ((const ElfW(Word) *) dsocaps)[-1]; - GLRO(dl_hwcap) |= (uint64_t) mask << _DL_FIRST_EXTRA; - /* Note that we add the dsocaps to the set already chosen by the - LD_HWCAP_MASK environment variable (or default HWCAP_IMPORTANT). - So there is no way to request ignoring an OS-supplied dsocap - string and bit like you can ignore an OS-supplied HWCAP bit. */ - GLRO(dl_hwcap_mask) |= (uint64_t) mask << _DL_FIRST_EXTRA; - size_t len; - for (const char *p = dsocaps; p < dsocaps + dsocapslen; p += len + 1) - { - uint_fast8_t bit = *p++; - len = strlen (p); - - /* Skip entries that are not enabled in the mask word. */ - if (__builtin_expect (mask & ((ElfW(Word)) 1 << bit), 1)) - { - temp[m].str = p; - temp[m].len = len; - ++m; - } - else - --cnt; - } - } -#endif - for (n = 0; masked != 0; ++n) - if ((masked & (1ULL << n)) != 0) - { - temp[m].str = _dl_hwcap_string (n); - temp[m].len = strlen (temp[m].str); - masked ^= 1ULL << n; - ++m; - } - if (platform != NULL) - { - temp[m].str = platform; - temp[m].len = platform_len; - ++m; - } - - temp[m].str = "tls"; - temp[m].len = 3; - ++m; - - assert (m == cnt); - - /* Determine the total size of all strings together. */ - if (cnt == 1) - total = temp[0].len + 1; - else - { - total = temp[0].len + temp[cnt - 1].len + 2; - if (cnt > 2) - { - total <<= 1; - for (n = 1; n + 1 < cnt; ++n) - total += temp[n].len + 1; - if (cnt > 3 - && (cnt >= sizeof (size_t) * 8 - || total + (sizeof (*result) << 3) - >= (1UL << (sizeof (size_t) * 8 - cnt + 3)))) - _dl_signal_error (ENOMEM, NULL, NULL, - N_("cannot create capability list")); - - total <<= cnt - 3; - } - } - - /* The result structure: we use a very compressed way to store the - various combinations of capability names. */ - *sz = 1 << cnt; - result = (struct r_strlenpair *) malloc (*sz * sizeof (*result) + total); - if (result == NULL) - _dl_signal_error (ENOMEM, NULL, NULL, - N_("cannot create capability list")); - - if (cnt == 1) - { - result[0].str = (char *) (result + *sz); - result[0].len = temp[0].len + 1; - result[1].str = (char *) (result + *sz); - result[1].len = 0; - cp = __mempcpy ((char *) (result + *sz), temp[0].str, temp[0].len); - *cp = '/'; - *sz = 2; - *max_capstrlen = result[0].len; - - return result; - } - - /* Fill in the information. This follows the following scheme - (indeces from TEMP for four strings): - entry #0: 0, 1, 2, 3 binary: 1111 - #1: 0, 1, 3 1101 - #2: 0, 2, 3 1011 - #3: 0, 3 1001 - This allows the representation of all possible combinations of - capability names in the string. First generate the strings. */ - result[1].str = result[0].str = cp = (char *) (result + *sz); -#define add(idx) \ - cp = __mempcpy (__mempcpy (cp, temp[idx].str, temp[idx].len), "/", 1); - if (cnt == 2) - { - add (1); - add (0); - } - else - { - n = 1 << (cnt - 1); - do - { - n -= 2; - - /* We always add the last string. */ - add (cnt - 1); - - /* Add the strings which have the bit set in N. */ - for (m = cnt - 2; m > 0; --m) - if ((n & (1 << m)) != 0) - add (m); - - /* Always add the first string. */ - add (0); - } - while (n != 0); - } -#undef add - - /* Now we are ready to install the string pointers and length. */ - for (n = 0; n < (1UL << cnt); ++n) - result[n].len = 0; - n = cnt; - do - { - size_t mask = 1 << --n; - - rp = result; - for (m = 1 << cnt; m > 0; ++rp) - if ((--m & mask) != 0) - rp->len += temp[n].len + 1; - } - while (n != 0); - - /* The first half of the strings all include the first string. */ - n = (1 << cnt) - 2; - rp = &result[2]; - while (n != (1UL << (cnt - 1))) - { - if ((--n & 1) != 0) - rp[0].str = rp[-2].str + rp[-2].len; - else - rp[0].str = rp[-1].str; - ++rp; - } - - /* The second half starts right after the first part of the string of - the corresponding entry in the first half. */ - do - { - rp[0].str = rp[-(1 << (cnt - 1))].str + temp[cnt - 1].len + 1; - ++rp; - } - while (--n != 0); - - /* The maximum string length. */ - *max_capstrlen = result[0].len; - - return result; -} - #endif |