Revision 68a1c816 linux-user/mmap.c
| b/linux-user/mmap.c | ||
|---|---|---|
| 216 | 216 |
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| 217 | 217 |
unsigned long last_brk; |
| 218 | 218 |
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/* Subroutine of mmap_find_vma, used when we have pre-allocated a chunk |
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of guest address space. */ |
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static abi_ulong mmap_find_vma_reserved(abi_ulong start, abi_ulong size) |
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{
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abi_ulong addr; |
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abi_ulong last_addr; |
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int prot; |
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int looped = 0; |
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if (size > reserved_va) {
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return (abi_ulong)-1; |
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} |
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last_addr = start; |
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for (addr = start; last_addr + size != addr; addr += qemu_host_page_size) {
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if (last_addr + size >= reserved_va |
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|| (abi_ulong)(last_addr + size) < last_addr) {
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if (looped) {
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return (abi_ulong)-1; |
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} |
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last_addr = qemu_host_page_size; |
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addr = 0; |
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looped = 1; |
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continue; |
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} |
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prot = page_get_flags(addr); |
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if (prot) {
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last_addr = addr + qemu_host_page_size; |
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} |
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} |
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mmap_next_start = addr; |
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return last_addr; |
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} |
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|
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| 219 | 253 |
/* |
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* Find and reserve a free memory area of size 'size'. The search |
| 221 | 255 |
* starts at 'start'. |
| ... | ... | |
| 237 | 271 |
|
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size = HOST_PAGE_ALIGN(size); |
| 239 | 273 |
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if (reserved_va) {
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return mmap_find_vma_reserved(start, size); |
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} |
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|
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addr = start; |
| 241 | 279 |
wrapped = repeat = 0; |
| 242 | 280 |
prev = 0; |
| ... | ... | |
| 525 | 563 |
return -1; |
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} |
| 527 | 565 |
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static void mmap_reserve(abi_ulong start, abi_ulong size) |
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{
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abi_ulong real_start; |
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abi_ulong real_end; |
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abi_ulong addr; |
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abi_ulong end; |
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int prot; |
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|
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real_start = start & qemu_host_page_mask; |
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real_end = HOST_PAGE_ALIGN(start + size); |
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end = start + size; |
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if (start > real_start) {
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/* handle host page containing start */ |
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prot = 0; |
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for (addr = real_start; addr < start; addr += TARGET_PAGE_SIZE) {
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prot |= page_get_flags(addr); |
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} |
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if (real_end == real_start + qemu_host_page_size) {
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for (addr = end; addr < real_end; addr += TARGET_PAGE_SIZE) {
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prot |= page_get_flags(addr); |
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} |
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end = real_end; |
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} |
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if (prot != 0) |
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real_start += qemu_host_page_size; |
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} |
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if (end < real_end) {
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prot = 0; |
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for (addr = end; addr < real_end; addr += TARGET_PAGE_SIZE) {
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prot |= page_get_flags(addr); |
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} |
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if (prot != 0) |
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real_end -= qemu_host_page_size; |
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} |
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if (real_start != real_end) {
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mmap(g2h(real_start), real_end - real_start, PROT_NONE, |
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MAP_FIXED | MAP_ANONYMOUS | MAP_PRIVATE | MAP_NORESERVE, |
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-1, 0); |
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} |
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} |
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|
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| 528 | 607 |
int target_munmap(abi_ulong start, abi_ulong len) |
| 529 | 608 |
{
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| 530 | 609 |
abi_ulong end, real_start, real_end, addr; |
| ... | ... | |
| 572 | 651 |
ret = 0; |
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/* unmap what we can */ |
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if (real_start < real_end) {
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ret = munmap(g2h(real_start), real_end - real_start); |
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if (reserved_va) {
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mmap_reserve(real_start, real_end - real_start); |
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} else {
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ret = munmap(g2h(real_start), real_end - real_start); |
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} |
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| 576 | 659 |
} |
| 577 | 660 |
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if (ret == 0) |
| ... | ... | |
| 590 | 673 |
|
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mmap_lock(); |
| 592 | 675 |
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if (flags & MREMAP_FIXED) |
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if (flags & MREMAP_FIXED) {
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host_addr = (void *) syscall(__NR_mremap, g2h(old_addr), |
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old_size, new_size, |
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flags, |
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new_addr); |
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else if (flags & MREMAP_MAYMOVE) {
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g2h(new_addr)); |
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if (reserved_va && host_addr != MAP_FAILED) {
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/* If new and old addresses overlap then the above mremap will |
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already have failed with EINVAL. */ |
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mmap_reserve(old_addr, old_size); |
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} |
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} else if (flags & MREMAP_MAYMOVE) {
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abi_ulong mmap_start; |
| 600 | 689 |
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mmap_start = mmap_find_vma(0, new_size); |
| ... | ... | |
| 603 | 692 |
if (mmap_start == -1) {
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| 604 | 693 |
errno = ENOMEM; |
| 605 | 694 |
host_addr = MAP_FAILED; |
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} else |
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} else {
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host_addr = (void *) syscall(__NR_mremap, g2h(old_addr), |
| 608 | 697 |
old_size, new_size, |
| 609 | 698 |
flags | MREMAP_FIXED, |
| 610 | 699 |
g2h(mmap_start)); |
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mmap_reserve(old_addr, old_size); |
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} |
|
| 611 | 702 |
} else {
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host_addr = mremap(g2h(old_addr), old_size, new_size, flags); |
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int prot = 0; |
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if (reserved_va && old_size < new_size) {
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abi_ulong addr; |
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for (addr = old_addr + old_size; |
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addr < old_addr + new_size; |
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addr++) {
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prot |= page_get_flags(addr); |
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} |
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} |
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if (prot == 0) {
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host_addr = mremap(g2h(old_addr), old_size, new_size, flags); |
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if (host_addr != MAP_FAILED && reserved_va && old_size > new_size) {
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mmap_reserve(old_addr + old_size, new_size - old_size); |
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} |
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} else {
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errno = ENOMEM; |
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host_addr = MAP_FAILED; |
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} |
|
| 613 | 721 |
/* Check if address fits target address space */ |
| 614 | 722 |
if ((unsigned long)host_addr + new_size > (abi_ulong)-1) {
|
| 615 | 723 |
/* Revert mremap() changes */ |
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