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-rw-r--r--sysdeps/nacl/dl-map-segments.h264
1 files changed, 0 insertions, 264 deletions
diff --git a/sysdeps/nacl/dl-map-segments.h b/sysdeps/nacl/dl-map-segments.h
deleted file mode 100644
index ec3eff8a60..0000000000
--- a/sysdeps/nacl/dl-map-segments.h
+++ /dev/null
@@ -1,264 +0,0 @@
-/* Map in a shared object's segments. NaCl version.
- Copyright (C) 2015-2016 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 <dl-load.h>
-#include <errno.h>
-#include <stdbool.h>
-#include <unistd.h>
-#include <libc-internal.h>
-
-
-/* This is basically pread, but with iteration after short reads. */
-static bool
-read_in_data (int fd, void *data, size_t len, off_t pos)
-{
- if (__glibc_unlikely (__lseek (fd, pos, SEEK_SET) == (off_t) -1))
- return true;
- while (len > 0)
- {
- ssize_t n = __read (fd, data, len);
- if (__glibc_unlikely (n < 0))
- return true;
- if (__glibc_unlikely (n == 0))
- {
- errno = EFTYPE;
- return true;
- }
- data += n;
- len -= n;
- }
- return false;
-}
-
-static const char *
-_dl_map_segments (struct link_map *l, int fd,
- const ElfW(Ehdr) *header, int type,
- const struct loadcmd loadcmds[], size_t nloadcmds,
- const size_t maplength, bool has_holes,
- struct link_map *loader)
-{
- if (__glibc_likely (type == ET_DYN))
- {
- /* This is a position-independent shared object. Let the system
- choose where to place it.
-
- As a refinement, sometimes we have an address that we would
- prefer to map such objects at; but this is only a preference,
- the OS can do whatever it likes. */
- ElfW(Addr) mappref
- = (ELF_PREFERRED_ADDRESS (loader, maplength,
- loadcmds[0].mapstart & GLRO(dl_use_load_bias))
- - MAP_BASE_ADDR (l));
-
- uintptr_t mapstart;
- if (__glibc_likely (loadcmds[0].prot & PROT_EXEC))
- {
- /* When there is a code segment, we must use the
- allocate_code_data interface to choose a location. */
-
- uintptr_t code_size = loadcmds[0].allocend - loadcmds[0].mapstart;
- uintptr_t data_offset;
- size_t data_size;
-
- if (__glibc_likely (nloadcmds > 1))
- {
- data_offset = loadcmds[1].mapstart - loadcmds[0].mapstart;
- data_size = ALIGN_UP (maplength - data_offset,
- GLRO(dl_pagesize));
- }
- else
- {
- data_offset = 0;
- data_size = 0;
- }
-
- int error = __nacl_irt_code_data_alloc.allocate_code_data
- (mappref, code_size, data_offset, data_size, &mapstart);
- if (__glibc_unlikely (error))
- {
- errno = error;
- return DL_MAP_SEGMENTS_ERROR_MAP_SEGMENT;
- }
- }
- else
- {
- /* With no code pages involved, plain mmap works fine. */
- void *mapped = __mmap ((void *) mappref, maplength,
- PROT_NONE, MAP_ANON, -1, 0);
- if (__glibc_unlikely (mapped == MAP_FAILED))
- return DL_MAP_SEGMENTS_ERROR_MAP_SEGMENT;
- mapstart = (uintptr_t) mapped;
- }
-
- l->l_addr = mapstart - loadcmds[0].mapstart;
- }
-
- /* Remember which part of the address space this object uses. */
- l->l_map_start = loadcmds[0].mapstart + l->l_addr;
- l->l_map_end = l->l_map_start + maplength;
- l->l_contiguous = !has_holes;
-
- /* Now actually map (or read) in each segment. */
- for (const struct loadcmd *c = loadcmds; c < &loadcmds[nloadcmds]; ++c)
- if (__glibc_likely (c->mapend > c->mapstart))
- {
- /* Unlike POSIX mmap, NaCl's mmap does not reliably handle COW
- faults in the remainder of the final partial page. So to get
- the expected behavior for the unaligned boundary between data
- and bss, it's necessary to allocate the final partial page of
- data as anonymous memory rather than mapping it from the file. */
-
- size_t maplen = c->mapend - c->mapstart;
- if (c->mapend > c->dataend && c->allocend > c->dataend)
- maplen = (c->dataend & -GLRO(dl_pagesize)) - c->mapstart;
-
- /* Map the segment contents from the file. */
- if (__glibc_unlikely (__mmap ((void *) (l->l_addr + c->mapstart),
- maplen, c->prot,
- MAP_FIXED|MAP_COPY|MAP_FILE,
- fd, c->mapoff)
- == MAP_FAILED))
- {
- switch (errno)
- {
- case EINVAL:
- case ENOTSUP:
- case ENOSYS:
- break;
- default:
- return DL_MAP_SEGMENTS_ERROR_MAP_SEGMENT;
- }
-
- /* No mmap support for this file. */
- if (c->prot & PROT_EXEC)
- {
- /* Read the data into a temporary buffer. */
- const size_t len = c->mapend - c->mapstart;
- void *data = __mmap (NULL, len, PROT_READ | PROT_WRITE,
- MAP_ANON|MAP_PRIVATE, -1, 0);
- if (__glibc_unlikely (data == MAP_FAILED))
- return DL_MAP_SEGMENTS_ERROR_MAP_ZERO_FILL;
- if (read_in_data (fd, data, len, c->mapoff))
- return DL_MAP_SEGMENTS_ERROR_MAP_SEGMENT;
- /* Now validate and install the code. */
- int error = __nacl_irt_dyncode.dyncode_create
- ((void *) (l->l_addr + c->mapstart), data, len);
- __munmap (data, len);
- if (__glibc_unlikely (error))
- {
- errno = error;
- return DL_MAP_SEGMENTS_ERROR_MAP_SEGMENT;
- }
- if (__glibc_unlikely (type != ET_DYN))
- {
- /* A successful PROT_EXEC mmap would have implicitly
- updated the bookkeeping so that a future
- allocate_code_data call would know that this range
- of the address space is already occupied. That
- doesn't happen implicitly with dyncode_create, so
- it's necessary to do an explicit call to update the
- bookkeeping. */
- uintptr_t allocated_address;
- error = __nacl_irt_code_data_alloc.allocate_code_data
- (l->l_addr + c->mapstart, len, 0, 0, &allocated_address);
- if (__glibc_unlikely (error))
- {
- errno = error;
- return DL_MAP_SEGMENTS_ERROR_MAP_SEGMENT;
- }
- if (__glibc_unlikely
- (allocated_address != l->l_addr + c->mapstart))
- {
- /* This is not a very helpful error for this case,
- but there isn't really anything better to use. */
- errno = ENOMEM;
- return DL_MAP_SEGMENTS_ERROR_MAP_SEGMENT;
- }
- }
- }
- else
- {
- /* Allocate the pages. */
- if (__mmap ((void *) (l->l_addr + c->mapstart),
- c->mapend - c->mapstart, c->prot | PROT_WRITE,
- MAP_FIXED|MAP_ANON|MAP_PRIVATE, -1, 0)
- == MAP_FAILED)
- return DL_MAP_SEGMENTS_ERROR_MAP_ZERO_FILL;
- /* Now read in the data. */
- if (read_in_data (fd, (void *) (l->l_addr + c->mapstart),
- c->dataend - c->mapstart, c->mapoff))
- return DL_MAP_SEGMENTS_ERROR_MAP_SEGMENT;
- /* Now that we've filled the pages, reset the page
- protections to what they should be. */
- if (!(c->prot & PROT_WRITE)
- && __mprotect ((void *) (l->l_addr + c->mapstart),
- c->mapend - c->mapstart, c->prot) < 0)
- return DL_MAP_SEGMENTS_ERROR_MPROTECT;
- }
- }
- else if (c->allocend > c->dataend)
- {
- /* Extra zero pages should appear at the end of this segment,
- after the data mapped from the file. */
-
- uintptr_t allocend = c->mapend;
- if (c->mapend > c->dataend)
- {
- /* The final data page was partial. So we didn't map it in.
- Instead, we must allocate an anonymous page to fill. */
- if (c->prot & PROT_WRITE)
- /* Do the whole allocation right here. */
- allocend = c->allocend;
- if (__mmap ((void *) (l->l_addr + c->mapstart + maplen),
- allocend - (c->mapstart + maplen), c->prot,
- MAP_FIXED|MAP_ANON|MAP_PRIVATE, -1, 0)
- == MAP_FAILED)
- return DL_MAP_SEGMENTS_ERROR_MAP_ZERO_FILL;
- if (read_in_data (fd,
- (void *) (l->l_addr + c->mapstart + maplen),
- c->dataend & (GLRO(dl_pagesize) - 1),
- c->mapoff + maplen))
- return DL_MAP_SEGMENTS_ERROR_MAP_SEGMENT;
- /* Now that we've filled the page, reset its
- protections to what they should be. */
- if (!(c->prot & PROT_WRITE)
- && __mprotect ((void *) (l->l_addr + c->mapstart + maplen),
- c->mapend - (c->mapstart + maplen),
- c->prot) < 0)
- return DL_MAP_SEGMENTS_ERROR_MPROTECT;
- }
-
- /* Now allocate the pure zero-fill pages. */
- if (allocend < c->allocend
- && (__mmap ((void *) (l->l_addr + c->mapstart + allocend),
- c->allocend - (c->mapstart + allocend), c->prot,
- MAP_FIXED|MAP_ANON|MAP_PRIVATE, -1, 0)
- == MAP_FAILED))
- return DL_MAP_SEGMENTS_ERROR_MAP_ZERO_FILL;
- }
-
- _dl_postprocess_loadcmd (l, header, c);
- }
-
- /* Notify ELF_PREFERRED_ADDRESS that we have to load this one
- fixed. */
- ELF_FIXED_ADDRESS (loader, c->mapstart);
-
- return NULL;
-}
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