X-Git-Url: https://repo.jachan.dev/qemu.git/blobdiff_plain/80210bcd719c615d3ae9cd851e9e961bac722538..4cbea5986981998cda07b13794c7e3ff7bc42e80:/linux-user/mmap.c
diff --git a/linux-user/mmap.c b/linux-user/mmap.c
index f87303402d..88276e77f8 100644
--- a/linux-user/mmap.c
+++ b/linux-user/mmap.c
@@ -14,8 +14,7 @@
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ * along with this program; if not, see .
*/
#include
#include
@@ -23,12 +22,51 @@
#include
#include
#include
+#include
+#include
#include
+#include
+#include
#include "qemu.h"
+#include "qemu-common.h"
+#include "translate-all.h"
//#define DEBUG_MMAP
+static pthread_mutex_t mmap_mutex = PTHREAD_MUTEX_INITIALIZER;
+static __thread int mmap_lock_count;
+
+void mmap_lock(void)
+{
+ if (mmap_lock_count++ == 0) {
+ pthread_mutex_lock(&mmap_mutex);
+ }
+}
+
+void mmap_unlock(void)
+{
+ if (--mmap_lock_count == 0) {
+ pthread_mutex_unlock(&mmap_mutex);
+ }
+}
+
+/* Grab lock to make sure things are in a consistent state after fork(). */
+void mmap_fork_start(void)
+{
+ if (mmap_lock_count)
+ abort();
+ pthread_mutex_lock(&mmap_mutex);
+}
+
+void mmap_fork_end(int child)
+{
+ if (child)
+ pthread_mutex_init(&mmap_mutex, NULL);
+ else
+ pthread_mutex_unlock(&mmap_mutex);
+}
+
/* NOTE: all the constants are the HOST ones, but addresses are target. */
int target_mprotect(abi_ulong start, abi_ulong len, int prot)
{
@@ -36,8 +74,8 @@ int target_mprotect(abi_ulong start, abi_ulong len, int prot)
int prot1, ret;
#ifdef DEBUG_MMAP
- printf("mprotect: start=0x" TARGET_FMT_lx
- "len=0x" TARGET_FMT_lx " prot=%c%c%c\n", start, len,
+ printf("mprotect: start=0x" TARGET_ABI_FMT_lx
+ "len=0x" TARGET_ABI_FMT_lx " prot=%c%c%c\n", start, len,
prot & PROT_READ ? 'r' : '-',
prot & PROT_WRITE ? 'w' : '-',
prot & PROT_EXEC ? 'x' : '-');
@@ -49,11 +87,11 @@ int target_mprotect(abi_ulong start, abi_ulong len, int prot)
end = start + len;
if (end < start)
return -EINVAL;
- if (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC))
- return -EINVAL;
+ prot &= PROT_READ | PROT_WRITE | PROT_EXEC;
if (len == 0)
return 0;
+ mmap_lock();
host_start = start & qemu_host_page_mask;
host_end = HOST_PAGE_ALIGN(end);
if (start > host_start) {
@@ -70,7 +108,7 @@ int target_mprotect(abi_ulong start, abi_ulong len, int prot)
}
ret = mprotect(g2h(host_start), qemu_host_page_size, prot1 & PAGE_BITS);
if (ret != 0)
- return ret;
+ goto error;
host_start += qemu_host_page_size;
}
if (end < host_end) {
@@ -81,7 +119,7 @@ int target_mprotect(abi_ulong start, abi_ulong len, int prot)
ret = mprotect(g2h(host_end - qemu_host_page_size), qemu_host_page_size,
prot1 & PAGE_BITS);
if (ret != 0)
- return ret;
+ goto error;
host_end -= qemu_host_page_size;
}
@@ -89,10 +127,14 @@ int target_mprotect(abi_ulong start, abi_ulong len, int prot)
if (host_start < host_end) {
ret = mprotect(g2h(host_start), host_end - host_start, prot);
if (ret != 0)
- return ret;
+ goto error;
}
page_set_flags(start, start + len, prot | PAGE_VALID);
+ mmap_unlock();
return 0;
+error:
+ mmap_unlock();
+ return ret;
}
/* map an incomplete host page */
@@ -130,14 +172,15 @@ static int mmap_frag(abi_ulong real_start,
possible while it is a shared mapping */
if ((flags & MAP_TYPE) == MAP_SHARED &&
(prot & PROT_WRITE))
- return -EINVAL;
+ return -1;
/* adjust protection to be able to read */
if (!(prot1 & PROT_WRITE))
mprotect(host_start, qemu_host_page_size, prot1 | PROT_WRITE);
/* read the corresponding file data */
- pread(fd, g2h(start), end - start, offset);
+ if (pread(fd, g2h(start), end - start, offset) == -1)
+ return -1;
/* put final protection */
if (prot_new != (prot1 | PROT_WRITE))
@@ -151,24 +194,186 @@ static int mmap_frag(abi_ulong real_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
+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'.
+ * It must be called with mmap_lock() held.
+ * Return -1 if error.
+ */
+abi_ulong mmap_find_vma(abi_ulong start, abi_ulong size)
+{
+ void *ptr, *prev;
+ abi_ulong addr;
+ int wrapped, repeat;
+
+ /* If 'start' == 0, then a default start address is used. */
+ if (start == 0) {
+ start = mmap_next_start;
+ } else {
+ start &= qemu_host_page_mask;
+ }
+
+ size = HOST_PAGE_ALIGN(size);
+
+ if (RESERVED_VA) {
+ return mmap_find_vma_reserved(start, size);
+ }
+
+ addr = start;
+ wrapped = repeat = 0;
+ prev = 0;
+
+ for (;; prev = ptr) {
+ /*
+ * Reserve needed memory area to avoid a race.
+ * It should be discarded using:
+ * - mmap() with MAP_FIXED flag
+ * - mremap() with MREMAP_FIXED flag
+ * - shmat() with SHM_REMAP flag
+ */
+ ptr = mmap(g2h(addr), size, PROT_NONE,
+ MAP_ANONYMOUS|MAP_PRIVATE|MAP_NORESERVE, -1, 0);
+
+ /* ENOMEM, if host address space has no memory */
+ if (ptr == MAP_FAILED) {
+ return (abi_ulong)-1;
+ }
+
+ /* Count the number of sequential returns of the same address.
+ This is used to modify the search algorithm below. */
+ repeat = (ptr == prev ? repeat + 1 : 0);
+
+ if (h2g_valid(ptr + size - 1)) {
+ addr = h2g(ptr);
+
+ if ((addr & ~TARGET_PAGE_MASK) == 0) {
+ /* Success. */
+ if (start == mmap_next_start && addr >= TASK_UNMAPPED_BASE) {
+ mmap_next_start = addr + size;
+ }
+ return addr;
+ }
+
+ /* The address is not properly aligned for the target. */
+ switch (repeat) {
+ case 0:
+ /* Assume the result that the kernel gave us is the
+ first with enough free space, so start again at the
+ next higher target page. */
+ addr = TARGET_PAGE_ALIGN(addr);
+ break;
+ case 1:
+ /* Sometimes the kernel decides to perform the allocation
+ at the top end of memory instead. */
+ addr &= TARGET_PAGE_MASK;
+ break;
+ case 2:
+ /* Start over at low memory. */
+ addr = 0;
+ break;
+ default:
+ /* Fail. This unaligned block must the last. */
+ addr = -1;
+ break;
+ }
+ } else {
+ /* Since the result the kernel gave didn't fit, start
+ again at low memory. If any repetition, fail. */
+ addr = (repeat ? -1 : 0);
+ }
+
+ /* Unmap and try again. */
+ munmap(ptr, size);
+
+ /* ENOMEM if we checked the whole of the target address space. */
+ if (addr == (abi_ulong)-1) {
+ return (abi_ulong)-1;
+ } else if (addr == 0) {
+ if (wrapped) {
+ return (abi_ulong)-1;
+ }
+ wrapped = 1;
+ /* Don't actually use 0 when wrapping, instead indicate
+ 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);
+ } else if (wrapped && addr >= start) {
+ return (abi_ulong)-1;
+ }
+ }
+}
+
/* 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
+ mmap_lock();
#ifdef DEBUG_MMAP
{
- printf("mmap: start=0x" TARGET_FMT_lx
- " len=0x" TARGET_FMT_lx " prot=%c%c%c flags=",
+ printf("mmap: start=0x" TARGET_ABI_FMT_lx
+ " len=0x" TARGET_ABI_FMT_lx " prot=%c%c%c flags=",
start, len,
prot & PROT_READ ? 'r' : '-',
prot & PROT_WRITE ? 'w' : '-',
@@ -188,172 +393,231 @@ abi_long target_mmap(abi_ulong start, abi_ulong len, int prot,
printf("[MAP_TYPE=0x%x] ", flags & MAP_TYPE);
break;
}
- printf("fd=%d offset=" TARGET_FMT_lx "\n", fd, offset);
+ printf("fd=%d offset=" TARGET_ABI_FMT_lx "\n", fd, offset);
}
#endif
if (offset & ~TARGET_PAGE_MASK) {
errno = EINVAL;
- return -1;
+ goto fail;
}
len = TARGET_PAGE_ALIGN(len);
if (len == 0)
- return start;
+ 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)) {
-#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);
+ 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;
}
-#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;
+ /* When mapping files into a memory area larger than the file, accesses
+ to pages beyond the file size will cause a SIGBUS.
+
+ For example, if mmaping a file of 100 bytes on a host with 4K pages
+ emulating a target with 8K pages, the target expects to be able to
+ access the first 8K. But the host will trap us on any access beyond
+ 4K.
+
+ When emulating a target with a larger page-size than the hosts, we
+ 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 (fstat (fd, &sb) == -1)
+ goto fail;
+
+ /* Are we trying to create a map beyond EOF?. */
+ if (offset + len > sb.st_size) {
+ /* 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);
+ }
+ }
- start = h2g(host_aligned_start);
- end = start + TARGET_PAGE_ALIGN(len);
+ if (!(flags & MAP_FIXED)) {
+ unsigned long host_start;
+ void *p;
- /* 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);
+ host_len = len + offset - host_offset;
+ host_len = HOST_PAGE_ALIGN(host_len);
- 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;
+ /* 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(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(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;
}
- }
-
- 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)) {
+ start = h2g(host_start);
+ } else {
+ if (start & ~TARGET_PAGE_MASK) {
errno = EINVAL;
- return -1;
+ goto fail;
}
- 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);
+
+ /*
+ * Test if requested memory area fits target address space
+ * It can fail only on 64-bit host with 32-bit target.
+ * On any other target/host host mmap() handles this error correctly.
+ */
+ if ((unsigned long)start + len - 1 > (abi_ulong) -1) {
+ errno = EINVAL;
+ goto fail;
}
- 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,
+ /* 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;
+ goto fail;
+ }
+ retaddr = target_mmap(start, len, prot | PROT_WRITE,
+ MAP_FIXED | MAP_PRIVATE | MAP_ANONYMOUS,
+ -1, 0);
+ if (retaddr == -1)
+ goto fail;
+ if (pread(fd, g2h(start), len, offset) == -1)
+ goto fail;
+ if (!(prot & PROT_WRITE)) {
+ ret = target_mprotect(start, len, prot);
+ if (ret != 0) {
+ start = 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,
+ prot, flags, fd, offset);
+ if (ret == -1)
+ goto fail;
+ 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;
+ goto fail;
+ 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)
+ goto fail;
+ 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)
+ goto fail;
+ }
}
the_end1:
page_set_flags(start, start + len, prot | PAGE_VALID);
the_end:
#ifdef DEBUG_MMAP
- printf("ret=0x%llx\n", start);
+ printf("ret=0x" TARGET_ABI_FMT_lx "\n", start);
page_dump(stdout);
printf("\n");
#endif
+ tb_invalidate_phys_range(start, start + len);
+ mmap_unlock();
return start;
+fail:
+ mmap_unlock();
+ 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)
@@ -362,13 +626,16 @@ int target_munmap(abi_ulong start, abi_ulong len)
int prot, ret;
#ifdef DEBUG_MMAP
- printf("munmap: start=0x%lx len=0x%lx\n", start, len);
+ printf("munmap: start=0x" TARGET_ABI_FMT_lx " len=0x"
+ TARGET_ABI_FMT_lx "\n",
+ start, len);
#endif
if (start & ~TARGET_PAGE_MASK)
return -EINVAL;
len = TARGET_PAGE_ALIGN(len);
if (len == 0)
return -EINVAL;
+ mmap_lock();
end = start + len;
real_start = start & qemu_host_page_mask;
real_end = HOST_PAGE_ALIGN(end);
@@ -397,34 +664,99 @@ int target_munmap(abi_ulong start, abi_ulong len)
real_end -= qemu_host_page_size;
}
+ ret = 0;
/* unmap what we can */
if (real_start < real_end) {
- ret = munmap(g2h(real_start), real_end - real_start);
- if (ret != 0)
- return ret;
+ if (RESERVED_VA) {
+ mmap_reserve(real_start, real_end - real_start);
+ } else {
+ ret = munmap(g2h(real_start), real_end - real_start);
+ }
}
- page_set_flags(start, start + len, 0);
- return 0;
+ if (ret == 0) {
+ page_set_flags(start, start + len, 0);
+ tb_invalidate_phys_range(start, start + len);
+ }
+ mmap_unlock();
+ return ret;
}
-/* XXX: currently, we only handle MAP_ANONYMOUS and not MAP_FIXED
- blocks which have been allocated starting on a host page */
abi_long target_mremap(abi_ulong old_addr, abi_ulong old_size,
abi_ulong new_size, unsigned long flags,
abi_ulong new_addr)
{
int prot;
- unsigned long host_addr;
-
- /* XXX: use 5 args syscall */
- host_addr = (long)mremap(g2h(old_addr), old_size, new_size, flags);
- if (host_addr == -1)
- return -1;
- new_addr = h2g(host_addr);
- prot = page_get_flags(old_addr);
- page_set_flags(old_addr, old_addr + old_size, 0);
- page_set_flags(new_addr, new_addr + new_size, prot | PAGE_VALID);
+ void *host_addr;
+
+ mmap_lock();
+
+ if (flags & MREMAP_FIXED) {
+ host_addr = (void *) syscall(__NR_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));
+ if ( RESERVED_VA ) {
+ mmap_reserve(old_addr, old_size);
+ }
+ }
+ } else {
+ 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 */
+ host_addr = mremap(g2h(old_addr), new_size, old_size, flags);
+ errno = ENOMEM;
+ host_addr = MAP_FAILED;
+ }
+ }
+
+ if (host_addr == MAP_FAILED) {
+ new_addr = -1;
+ } else {
+ new_addr = h2g(host_addr);
+ prot = page_get_flags(old_addr);
+ 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;
}
@@ -444,4 +776,3 @@ int target_msync(abi_ulong start, abi_ulong len, int flags)
start &= qemu_host_page_mask;
return msync(g2h(start), end - start, flags);
}
-