* You should have received a copy of the GNU General Public License
* along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
-#include <stdlib.h>
-#include <stdio.h>
-#include <stdarg.h>
-#include <string.h>
-#include <unistd.h>
-#include <errno.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <sys/mman.h>
-#include <linux/mman.h>
-#include <linux/unistd.h>
+#include "qemu/osdep.h"
#include "qemu.h"
#include "qemu-common.h"
+#include "translate-all.h"
//#define DEBUG_MMAP
-#if defined(CONFIG_USE_NPTL)
static pthread_mutex_t mmap_mutex = PTHREAD_MUTEX_INITIALIZER;
static __thread int mmap_lock_count;
}
}
+bool have_mmap_lock(void)
+{
+ return mmap_lock_count > 0 ? true : false;
+}
+
/* Grab lock to make sure things are in a consistent state after fork(). */
void mmap_fork_start(void)
{
else
pthread_mutex_unlock(&mmap_mutex);
}
-#else
-/* We aren't threadsafe to start with, so no need to worry about locking. */
-void mmap_lock(void)
-{
-}
-
-void mmap_unlock(void)
-{
-}
-#endif
/* NOTE: all the constants are the HOST ones, but addresses are target. */
int target_mprotect(abi_ulong start, abi_ulong len, int prot)
if (prot_new != (prot1 | PROT_WRITE))
mprotect(host_start, qemu_host_page_size, prot_new);
} else {
- /* just update the protection */
if (prot_new != prot1) {
mprotect(host_start, qemu_host_page_size, prot_new);
}
+ if (prot_new & PROT_WRITE) {
+ memset(g2h(start), 0, end - start);
+ }
}
return 0;
}
#if HOST_LONG_BITS == 64 && TARGET_ABI_BITS == 64
# define TASK_UNMAPPED_BASE (1ul << 38)
-#elif defined(__CYGWIN__)
-/* Cygwin doesn't have a whole lot of address space. */
-# define TASK_UNMAPPED_BASE 0x18000000
#else
# define TASK_UNMAPPED_BASE 0x40000000
#endif
-static abi_ulong mmap_next_start = TASK_UNMAPPED_BASE;
+abi_ulong mmap_next_start = TASK_UNMAPPED_BASE;
unsigned long last_brk;
+/* Subroutine of mmap_find_vma, used when we have pre-allocated a chunk
+ of guest address space. */
+static abi_ulong mmap_find_vma_reserved(abi_ulong start, abi_ulong size)
+{
+ abi_ulong addr;
+ abi_ulong end_addr;
+ int prot;
+ int looped = 0;
+
+ if (size > reserved_va) {
+ return (abi_ulong)-1;
+ }
+
+ size = HOST_PAGE_ALIGN(size);
+ end_addr = start + size;
+ if (end_addr > reserved_va) {
+ end_addr = reserved_va;
+ }
+ addr = end_addr - qemu_host_page_size;
+
+ while (1) {
+ if (addr > end_addr) {
+ if (looped) {
+ return (abi_ulong)-1;
+ }
+ end_addr = reserved_va;
+ addr = end_addr - qemu_host_page_size;
+ looped = 1;
+ continue;
+ }
+ prot = page_get_flags(addr);
+ if (prot) {
+ end_addr = addr;
+ }
+ if (addr + size == end_addr) {
+ break;
+ }
+ addr -= qemu_host_page_size;
+ }
+
+ if (start == mmap_next_start) {
+ mmap_next_start = addr;
+ }
+
+ return addr;
+}
+
/*
* Find and reserve a free memory area of size 'size'. The search
* starts at 'start'.
size = HOST_PAGE_ALIGN(size);
+ if (reserved_va) {
+ return mmap_find_vma_reserved(start, size);
+ }
+
addr = start;
wrapped = repeat = 0;
prev = 0;
munmap(ptr, size);
/* ENOMEM if we checked the whole of the target address space. */
- if (addr == -1ul) {
+ if (addr == (abi_ulong)-1) {
return (abi_ulong)-1;
} else if (addr == 0) {
if (wrapped) {
}
wrapped = 1;
/* Don't actually use 0 when wrapping, instead indicate
- that we'd truely like an allocation in low memory. */
+ that we'd truly like an allocation in low memory. */
addr = (mmap_min_addr > TARGET_PAGE_SIZE
? TARGET_PAGE_ALIGN(mmap_min_addr)
: TARGET_PAGE_SIZE);
int flags, int fd, abi_ulong offset)
{
abi_ulong ret, end, real_start, real_end, retaddr, host_offset, host_len;
- unsigned long host_start;
mmap_lock();
#ifdef DEBUG_MMAP
if (len == 0)
goto the_end;
real_start = start & qemu_host_page_mask;
+ host_offset = offset & qemu_host_page_mask;
+
+ /* If the user is asking for the kernel to find a location, do that
+ before we truncate the length for mapping files below. */
+ if (!(flags & MAP_FIXED)) {
+ host_len = len + offset - host_offset;
+ host_len = HOST_PAGE_ALIGN(host_len);
+ start = mmap_find_vma(real_start, host_len);
+ if (start == (abi_ulong)-1) {
+ errno = ENOMEM;
+ goto fail;
+ }
+ }
/* When mapping files into a memory area larger than the file, accesses
to pages beyond the file size will cause a SIGBUS.
may need to truncate file maps at EOF and add extra anonymous pages
up to the targets page boundary. */
- if ((qemu_real_host_page_size < TARGET_PAGE_SIZE)
- && !(flags & MAP_ANONYMOUS)) {
- struct stat sb;
+ if ((qemu_real_host_page_size < qemu_host_page_size) &&
+ !(flags & MAP_ANONYMOUS)) {
+ struct stat sb;
if (fstat (fd, &sb) == -1)
goto fail;
/* If so, truncate the file map at eof aligned with
the hosts real pagesize. Additional anonymous maps
will be created beyond EOF. */
- len = (sb.st_size - offset);
- len += qemu_real_host_page_size - 1;
- len &= ~(qemu_real_host_page_size - 1);
+ len = REAL_HOST_PAGE_ALIGN(sb.st_size - offset);
}
}
if (!(flags & MAP_FIXED)) {
- abi_ulong mmap_start;
+ unsigned long host_start;
void *p;
- host_offset = offset & qemu_host_page_mask;
+
host_len = len + offset - host_offset;
host_len = HOST_PAGE_ALIGN(host_len);
- mmap_start = mmap_find_vma(real_start, host_len);
- if (mmap_start == (abi_ulong)-1) {
- errno = ENOMEM;
- goto fail;
- }
+
/* Note: we prefer to control the mapping address. It is
especially important if qemu_host_page_size >
qemu_real_host_page_size */
- p = mmap(g2h(mmap_start),
- host_len, prot, flags | MAP_FIXED | MAP_ANONYMOUS, -1, 0);
+ p = mmap(g2h(start), host_len, prot,
+ flags | MAP_FIXED | MAP_ANONYMOUS, -1, 0);
if (p == MAP_FAILED)
goto fail;
/* update start so that it points to the file position at 'offset' */
host_start = (unsigned long)p;
if (!(flags & MAP_ANONYMOUS)) {
- p = mmap(g2h(mmap_start), len, prot,
+ p = mmap(g2h(start), len, prot,
flags | MAP_FIXED, fd, host_offset);
+ if (p == MAP_FAILED) {
+ munmap(g2h(start), host_len);
+ goto fail;
+ }
host_start += offset - host_offset;
}
start = h2g(host_start);
goto fail;
if (!(prot & PROT_WRITE)) {
ret = target_mprotect(start, len, prot);
- if (ret != 0) {
- start = ret;
- goto the_end;
- }
+ assert(ret == 0);
}
goto the_end;
}
/* handle the end of the mapping */
if (end < real_end) {
ret = mmap_frag(real_end - qemu_host_page_size,
- real_end - qemu_host_page_size, real_end,
+ real_end - qemu_host_page_size, end,
prot, flags, fd,
offset + real_end - qemu_host_page_size - start);
if (ret == -1)
page_dump(stdout);
printf("\n");
#endif
+ tb_invalidate_phys_range(start, start + len);
mmap_unlock();
return start;
fail:
return -1;
}
+static void mmap_reserve(abi_ulong start, abi_ulong size)
+{
+ abi_ulong real_start;
+ abi_ulong real_end;
+ abi_ulong addr;
+ abi_ulong end;
+ int prot;
+
+ real_start = start & qemu_host_page_mask;
+ real_end = HOST_PAGE_ALIGN(start + size);
+ end = start + size;
+ if (start > real_start) {
+ /* handle host page containing start */
+ prot = 0;
+ for (addr = real_start; addr < start; addr += TARGET_PAGE_SIZE) {
+ prot |= page_get_flags(addr);
+ }
+ if (real_end == real_start + qemu_host_page_size) {
+ for (addr = end; addr < real_end; addr += TARGET_PAGE_SIZE) {
+ prot |= page_get_flags(addr);
+ }
+ end = real_end;
+ }
+ if (prot != 0)
+ real_start += qemu_host_page_size;
+ }
+ if (end < real_end) {
+ prot = 0;
+ for (addr = end; addr < real_end; addr += TARGET_PAGE_SIZE) {
+ prot |= page_get_flags(addr);
+ }
+ if (prot != 0)
+ real_end -= qemu_host_page_size;
+ }
+ if (real_start != real_end) {
+ mmap(g2h(real_start), real_end - real_start, PROT_NONE,
+ MAP_FIXED | MAP_ANONYMOUS | MAP_PRIVATE | MAP_NORESERVE,
+ -1, 0);
+ }
+}
+
int target_munmap(abi_ulong start, abi_ulong len)
{
abi_ulong end, real_start, real_end, addr;
ret = 0;
/* unmap what we can */
if (real_start < real_end) {
- ret = munmap(g2h(real_start), real_end - real_start);
+ if (reserved_va) {
+ mmap_reserve(real_start, real_end - real_start);
+ } else {
+ ret = munmap(g2h(real_start), real_end - real_start);
+ }
}
- if (ret == 0)
+ if (ret == 0) {
page_set_flags(start, start + len, 0);
+ tb_invalidate_phys_range(start, start + len);
+ }
mmap_unlock();
return ret;
}
mmap_lock();
- if (flags & MREMAP_FIXED)
- host_addr = (void *) syscall(__NR_mremap, g2h(old_addr),
- old_size, new_size,
- flags,
- new_addr);
- else if (flags & MREMAP_MAYMOVE) {
+ if (flags & MREMAP_FIXED) {
+ host_addr = mremap(g2h(old_addr), old_size, new_size,
+ flags, g2h(new_addr));
+
+ if (reserved_va && host_addr != MAP_FAILED) {
+ /* If new and old addresses overlap then the above mremap will
+ already have failed with EINVAL. */
+ mmap_reserve(old_addr, old_size);
+ }
+ } else if (flags & MREMAP_MAYMOVE) {
abi_ulong mmap_start;
mmap_start = mmap_find_vma(0, new_size);
if (mmap_start == -1) {
errno = ENOMEM;
host_addr = MAP_FAILED;
- } else
- host_addr = (void *) syscall(__NR_mremap, g2h(old_addr),
- old_size, new_size,
- flags | MREMAP_FIXED,
- g2h(mmap_start));
+ } else {
+ host_addr = mremap(g2h(old_addr), old_size, new_size,
+ flags | MREMAP_FIXED, g2h(mmap_start));
+ if (reserved_va) {
+ mmap_reserve(old_addr, old_size);
+ }
+ }
} else {
- host_addr = mremap(g2h(old_addr), old_size, new_size, flags);
+ int prot = 0;
+ if (reserved_va && old_size < new_size) {
+ abi_ulong addr;
+ for (addr = old_addr + old_size;
+ addr < old_addr + new_size;
+ addr++) {
+ prot |= page_get_flags(addr);
+ }
+ }
+ if (prot == 0) {
+ host_addr = mremap(g2h(old_addr), old_size, new_size, flags);
+ if (host_addr != MAP_FAILED && reserved_va && old_size > new_size) {
+ mmap_reserve(old_addr + old_size, new_size - old_size);
+ }
+ } else {
+ errno = ENOMEM;
+ host_addr = MAP_FAILED;
+ }
/* Check if address fits target address space */
if ((unsigned long)host_addr + new_size > (abi_ulong)-1) {
/* Revert mremap() changes */
page_set_flags(old_addr, old_addr + old_size, 0);
page_set_flags(new_addr, new_addr + new_size, prot | PAGE_VALID);
}
+ tb_invalidate_phys_range(new_addr, new_addr + new_size);
mmap_unlock();
return new_addr;
}
projects / qemu.git / blobdiff