return 0;
}
+#if defined(__CYGWIN__)
+/* Cygwin doesn't have a whole lot of address space. */
+static abi_ulong mmap_next_start = 0x18000000;
+#else
+static abi_ulong mmap_next_start = 0x40000000;
+#endif
+
+/* find a free memory area of size 'size'. The search starts at
+ 'start'. If 'start' == 0, then a default start address is used.
+ Return -1 if error.
+*/
+/* XXX: should mark pages used by the host as reserved to be sure not
+ to use them. */
+static abi_ulong mmap_find_vma(abi_ulong start, abi_ulong size)
+{
+ abi_ulong addr, addr1, addr_start;
+ int prot;
+
+ size = HOST_PAGE_ALIGN(size);
+ start = start & qemu_host_page_mask;
+ addr = start;
+ if (addr == 0)
+ addr = mmap_next_start;
+ addr_start = addr;
+ for(;;) {
+ prot = 0;
+ for(addr1 = addr; addr1 < (addr + size); addr1 += TARGET_PAGE_SIZE) {
+ prot |= page_get_flags(addr1);
+ }
+ if (prot == 0)
+ break;
+ addr += qemu_host_page_size;
+ /* we found nothing */
+ if (addr == addr_start)
+ return (abi_ulong)-1;
+ }
+ if (start == 0)
+ mmap_next_start = addr + size;
+ return addr;
+}
+
/* NOTE: all the constants are the HOST ones */
abi_long target_mmap(abi_ulong start, abi_ulong len, int prot,
int flags, int fd, abi_ulong offset)
{
abi_ulong ret, end, real_start, real_end, retaddr, host_offset, host_len;
unsigned long host_start;
-#if defined(__alpha__) || defined(__sparc__) || defined(__x86_64__) || \
- defined(__ia64) || defined(__mips__)
- static abi_ulong last_start = 0x40000000;
-#elif defined(__CYGWIN__)
- /* Cygwin doesn't have a whole lot of address space. */
- static abi_ulong last_start = 0x18000000;
-#endif
#ifdef DEBUG_MMAP
{
real_start = start & qemu_host_page_mask;
if (!(flags & MAP_FIXED)) {
-#if defined(__alpha__) || defined(__sparc__) || defined(__x86_64__) || \
- defined(__ia64) || defined(__mips__) || defined(__CYGWIN__)
- /* tell the kernel to search at the same place as i386 */
- if (real_start == 0) {
- real_start = last_start;
- last_start += HOST_PAGE_ALIGN(len);
- }
-#endif
- host_offset = offset & qemu_host_page_mask;
- host_len = len + offset - host_offset;
-
- if (qemu_host_page_size > qemu_real_host_page_size) {
- /*
- * The guest expects to see mmapped areas aligned to it's pagesize.
- * If the host's real page size is smaller than the guest's, we need
- * to fixup the maps. It is done by allocating a larger area,
- * displacing the map (if needed) and finally chopping off the spare
- * room at the edges.
- */
-
- /*
- * We assume qemu_host_page_size is always the same as
- * TARGET_PAGE_SIZE, see exec.c. qemu_real_host_page_size is the
- * hosts real page size.
- */
- abi_ulong host_end;
- unsigned long host_aligned_start;
- void *p;
-
- host_len = HOST_PAGE_ALIGN(host_len + qemu_host_page_size
- - qemu_real_host_page_size);
- p = mmap(real_start ? g2h(real_start) : NULL,
- host_len, prot, flags, fd, host_offset);
- if (p == MAP_FAILED)
- return -1;
-
- host_start = (unsigned long)p;
- host_end = host_start + host_len;
-
- /* Find start and end, aligned to the targets pagesize with-in the
- large mmaped area. */
- host_aligned_start = TARGET_PAGE_ALIGN(host_start);
- if (!(flags & MAP_ANONYMOUS))
- host_aligned_start += offset - host_offset;
-
- start = h2g(host_aligned_start);
- end = start + TARGET_PAGE_ALIGN(len);
-
- /* Chop off the leftovers, if any. */
- if (host_aligned_start > host_start)
- munmap((void *)host_start, host_aligned_start - host_start);
- if (end < host_end)
- munmap((void *)g2h(end), host_end - end);
-
- goto the_end1;
- } else {
- /* if not fixed, no need to do anything */
- void *p = mmap(real_start ? g2h(real_start) : NULL,
- host_len, prot, flags, fd, host_offset);
- if (p == MAP_FAILED)
- return -1;
- /* update start so that it points to the file position at 'offset' */
- host_start = (unsigned long)p;
- if (!(flags & MAP_ANONYMOUS))
- host_start += offset - host_offset;
- start = h2g(host_start);
- goto the_end1;
+ abi_ulong mmap_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;
+ return -1;
}
- }
-
- if (start & ~TARGET_PAGE_MASK) {
- errno = EINVAL;
- return -1;
- }
- end = start + len;
- real_end = HOST_PAGE_ALIGN(end);
-
- /* worst case: we cannot map the file because the offset is not
- aligned, so we read it */
- if (!(flags & MAP_ANONYMOUS) &&
- (offset & ~qemu_host_page_mask) != (start & ~qemu_host_page_mask)) {
- /* msync() won't work here, so we return an error if write is
- possible while it is a shared mapping */
- if ((flags & MAP_TYPE) == MAP_SHARED &&
- (prot & PROT_WRITE)) {
+ /* 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, fd, host_offset);
+ if (p == MAP_FAILED)
+ return -1;
+ /* update start so that it points to the file position at 'offset' */
+ host_start = (unsigned long)p;
+ if (!(flags & MAP_ANONYMOUS))
+ host_start += offset - host_offset;
+ start = h2g(host_start);
+ } else {
+ if (start & ~TARGET_PAGE_MASK) {
errno = EINVAL;
return -1;
}
- retaddr = target_mmap(start, len, prot | PROT_WRITE,
- MAP_FIXED | MAP_PRIVATE | MAP_ANONYMOUS,
- -1, 0);
- if (retaddr == -1)
- return -1;
- pread(fd, g2h(start), len, offset);
- if (!(prot & PROT_WRITE)) {
- ret = target_mprotect(start, len, prot);
- if (ret != 0)
- return ret;
+ end = start + len;
+ real_end = HOST_PAGE_ALIGN(end);
+
+ /* worst case: we cannot map the file because the offset is not
+ aligned, so we read it */
+ if (!(flags & MAP_ANONYMOUS) &&
+ (offset & ~qemu_host_page_mask) != (start & ~qemu_host_page_mask)) {
+ /* msync() won't work here, so we return an error if write is
+ possible while it is a shared mapping */
+ if ((flags & MAP_TYPE) == MAP_SHARED &&
+ (prot & PROT_WRITE)) {
+ errno = EINVAL;
+ return -1;
+ }
+ retaddr = target_mmap(start, len, prot | PROT_WRITE,
+ MAP_FIXED | MAP_PRIVATE | MAP_ANONYMOUS,
+ -1, 0);
+ if (retaddr == -1)
+ return -1;
+ pread(fd, g2h(start), len, offset);
+ if (!(prot & PROT_WRITE)) {
+ ret = target_mprotect(start, len, prot);
+ if (ret != 0)
+ return ret;
+ }
+ goto the_end;
}
- goto the_end;
- }
-
- /* handle the start of the mapping */
- if (start > real_start) {
- if (real_end == real_start + qemu_host_page_size) {
- /* one single host page */
- ret = mmap_frag(real_start, start, end,
+
+ /* handle the start of the mapping */
+ if (start > real_start) {
+ if (real_end == real_start + qemu_host_page_size) {
+ /* one single host page */
+ ret = mmap_frag(real_start, start, end,
+ prot, flags, fd, offset);
+ if (ret == -1)
+ return ret;
+ goto the_end1;
+ }
+ ret = mmap_frag(real_start, start, real_start + qemu_host_page_size,
prot, flags, fd, offset);
if (ret == -1)
return ret;
- goto the_end1;
+ real_start += qemu_host_page_size;
+ }
+ /* 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,
+ prot, flags, fd,
+ offset + real_end - qemu_host_page_size - start);
+ if (ret == -1)
+ return -1;
+ real_end -= qemu_host_page_size;
}
- ret = mmap_frag(real_start, start, real_start + qemu_host_page_size,
- prot, flags, fd, offset);
- if (ret == -1)
- return ret;
- real_start += qemu_host_page_size;
- }
- /* 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,
- prot, flags, fd,
- offset + real_end - qemu_host_page_size - start);
- if (ret == -1)
- return -1;
- real_end -= qemu_host_page_size;
- }
- /* map the middle (easier) */
- if (real_start < real_end) {
- void *p;
- unsigned long offset1;
- if (flags & MAP_ANONYMOUS)
- offset1 = 0;
- else
- offset1 = offset + real_start - start;
- p = mmap(g2h(real_start), real_end - real_start,
- prot, flags, fd, offset1);
- if (p == MAP_FAILED)
- return -1;
+ /* map the middle (easier) */
+ if (real_start < real_end) {
+ void *p;
+ unsigned long offset1;
+ if (flags & MAP_ANONYMOUS)
+ offset1 = 0;
+ else
+ offset1 = offset + real_start - start;
+ p = mmap(g2h(real_start), real_end - real_start,
+ prot, flags, fd, offset1);
+ if (p == MAP_FAILED)
+ return -1;
+ }
}
the_end1:
page_set_flags(start, start + len, prot | PAGE_VALID);
projects / mirror_qemu.git / commitdiff