There's a compiler warning:
warning: incompatible pointer to integer conversion assigning to
'mach_vm_address_t' (aka 'unsigned long long') from 'void *'
[-Wint-conversion]
buf_rw = tcg_ctx->code_gen_buffer;
I changed it to
buf_rw = (mach_vm_address_t)tcg_ctx->code_gen_buffer;
Also, MAP_JIT doesn't work with the split mapping (it needs the same
entitlements that allows for RWX mapping) so I made the following
changes
@@ -1088,15 +1094,11 @@ static bool alloc_code_gen_buffer(size_t size,
int mirror, Error **errp)
return true;
}
#else
-static bool alloc_code_gen_buffer_anon(size_t size, int prot, Error **errp)
+static bool alloc_code_gen_buffer_anon(size_t size, int prot, int
flags, Error **errp)
{
- int flags = MAP_PRIVATE | MAP_ANONYMOUS;
void *buf;
-#ifdef CONFIG_DARWIN
- /* Applicable to both iOS and macOS (Apple Silicon). */
- flags |= MAP_JIT;
-#endif
+ flags |= MAP_PRIVATE | MAP_ANONYMOUS;
buf = mmap(NULL, size, prot, flags, -1, 0);
if (buf == MAP_FAILED) {
@@ -1211,7 +1213,7 @@ static bool
alloc_code_gen_buffer_mirror_vmremap(size_t size, Error **errp)
vm_prot_t cur_prot, max_prot;
/* Map the read-write portion via normal anon memory. */
- if (!alloc_code_gen_buffer_anon(size, PROT_READ | PROT_WRITE, errp)) {
+ if (!alloc_code_gen_buffer_anon(size, PROT_READ | PROT_WRITE, 0, errp)) {
return false;
}
@@ -1263,6 +1265,8 @@ static bool alloc_code_gen_buffer_mirror(size_t
size, Error **errp)
static bool alloc_code_gen_buffer(size_t size, int mirror, Error **errp)
{
+ int flags = 0;
+
if (mirror) {
Error *local_err = NULL;
if (alloc_code_gen_buffer_mirror(size, &local_err)) {
@@ -1283,8 +1287,11 @@ static bool alloc_code_gen_buffer(size_t size,
int mirror, Error **errp)
/* The tcg interpreter does not need execute permission. */
prot = PROT_READ | PROT_WRITE;
#endif
+#ifdef CONFIG_DARWIN
+ flags |= MAP_JIT;
+#endif
- return alloc_code_gen_buffer_anon(size, prot, errp);
+ return alloc_code_gen_buffer_anon(size, prot, flags, errp);
}
#endif /* USE_STATIC_CODE_GEN_BUFFER, WIN32, POSIX */
With this in addition to the iOS host patches, I was able to run it on
the iPad but am getting random crashes that I am continuing to debug.
-j
On Thu, Oct 29, 2020 at 5:49 PM Richard Henderson
<richard.hender...@linaro.org> wrote:
>
> Cribbed from code posted by Joelle van Dyne <j...@getutm.app>,
> and rearranged to a cleaner structure. Completely untested.
>
> Signed-off-by: Richard Henderson <richard.hender...@linaro.org>
> ---
> accel/tcg/translate-all.c | 68 ++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 67 insertions(+), 1 deletion(-)
>
> diff --git a/accel/tcg/translate-all.c b/accel/tcg/translate-all.c
> index 3e69ebd1d3..bf8263fdb4 100644
> --- a/accel/tcg/translate-all.c
> +++ b/accel/tcg/translate-all.c
> @@ -1093,6 +1093,11 @@ static bool alloc_code_gen_buffer_anon(size_t size,
> int prot, Error **errp)
> int flags = MAP_PRIVATE | MAP_ANONYMOUS;
> void *buf;
>
> +#ifdef CONFIG_DARWIN
> + /* Applicable to both iOS and macOS (Apple Silicon). */
> + flags |= MAP_JIT;
> +#endif
> +
> buf = mmap(NULL, size, prot, flags, -1, 0);
> if (buf == MAP_FAILED) {
> error_setg_errno(errp, errno,
> @@ -1182,13 +1187,74 @@ static bool alloc_code_gen_buffer_mirror_memfd(size_t
> size, Error **errp)
> qemu_madvise(buf_rx, size, QEMU_MADV_HUGEPAGE);
> return true;
> }
> -#endif
> +#endif /* CONFIG_LINUX */
> +
> +#ifdef CONFIG_DARWIN
> +#include <mach/mach.h>
> +
> +extern kern_return_t mach_vm_remap(vm_map_t target_task,
> + mach_vm_address_t *target_address,
> + mach_vm_size_t size,
> + mach_vm_offset_t mask,
> + int flags,
> + vm_map_t src_task,
> + mach_vm_address_t src_address,
> + boolean_t copy,
> + vm_prot_t *cur_protection,
> + vm_prot_t *max_protection,
> + vm_inherit_t inheritance);
> +
> +static bool alloc_code_gen_buffer_mirror_vmremap(size_t size, Error **errp)
> +{
> + kern_return_t ret;
> + mach_vm_address_t buf_rw, buf_rx;
> + vm_prot_t cur_prot, max_prot;
> +
> + /* Map the read-write portion via normal anon memory. */
> + if (!alloc_code_gen_buffer_anon(size, PROT_READ | PROT_WRITE, errp)) {
> + return false;
> + }
> +
> + buf_rw = tcg_ctx->code_gen_buffer;
> + buf_rx = 0;
> + ret = mach_vm_remap(mach_task_self(),
> + &buf_rx,
> + size,
> + 0,
> + VM_FLAGS_ANYWHERE | VM_FLAGS_RANDOM_ADDR,
> + mach_task_self(),
> + buf_rw,
> + false,
> + &cur_prot,
> + &max_prot,
> + VM_INHERIT_NONE);
> + if (ret != KERN_SUCCESS) {
> + /* TODO: Convert "ret" to a human readable error message. */
> + error_setg(errp, "vm_remap for jit mirror failed");
> + munmap((void *)buf_rw, size);
> + return false;
> + }
> +
> + if (mprotect((void *)buf_rx, size, PROT_READ | PROT_EXEC) != 0) {
> + error_setg_errno(errp, errno, "mprotect for jit mirror");
> + munmap((void *)buf_rx, size);
> + munmap((void *)buf_rw, size);
> + return false;
> + }
> +
> + tcg_rx_mirror_diff = buf_rx - buf_rw;
> + return true;
> +}
> +#endif /* CONFIG_DARWIN */
>
> static bool alloc_code_gen_buffer_mirror(size_t size, Error **errp)
> {
> if (TCG_TARGET_SUPPORT_MIRROR) {
> #ifdef CONFIG_LINUX
> return alloc_code_gen_buffer_mirror_memfd(size, errp);
> +#endif
> +#ifdef CONFIG_DARWIN
> + return alloc_code_gen_buffer_mirror_vmremap(size, errp);
> #endif
> }
> error_setg(errp, "jit split-rwx not supported");
> --
> 2.25.1
>
