[PATCH 15/17] bsd-user: target_mprotect: use helper host_page_size local

Warner Losh posted 17 patches 3 months, 3 weeks ago
[PATCH 15/17] bsd-user: target_mprotect: use helper host_page_size local
Posted by Warner Losh 3 months, 3 weeks ago
Use helper variable for host_page_size. Linux-user uses a similar helper
to make the code smaller after the multi-page-size migration.

Signed-off-by: Warner Losh <imp@bsdimp.com>
---
 bsd-user/mmap.c | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/bsd-user/mmap.c b/bsd-user/mmap.c
index 2118972f073..ffecf52a72a 100644
--- a/bsd-user/mmap.c
+++ b/bsd-user/mmap.c
@@ -63,6 +63,7 @@ void mmap_fork_end(int child)
 /* NOTE: all the constants are the HOST ones, but addresses are target. */
 int target_mprotect(abi_ulong start, abi_ulong len, int target_prot)
 {
+    int host_page_size = qemu_real_host_page_size();
     abi_ulong end, host_start, host_end, addr;
     int prot1, ret;
 
@@ -83,7 +84,7 @@ int target_mprotect(abi_ulong start, abi_ulong len, int target_prot)
         return 0;
 
     mmap_lock();
-    host_start = start & qemu_host_page_mask;
+    host_start = start & -host_page_size;
     host_end = HOST_PAGE_ALIGN(end);
     if (start > host_start) {
         /* handle host page containing start */
@@ -91,28 +92,28 @@ int target_mprotect(abi_ulong start, abi_ulong len, int target_prot)
         for (addr = host_start; addr < start; addr += TARGET_PAGE_SIZE) {
             prot1 |= page_get_flags(addr);
         }
-        if (host_end == host_start + qemu_host_page_size) {
+        if (host_end == host_start + host_page_size) {
             for (addr = end; addr < host_end; addr += TARGET_PAGE_SIZE) {
                 prot1 |= page_get_flags(addr);
             }
             end = host_end;
         }
         ret = mprotect(g2h_untagged(host_start),
-                       qemu_host_page_size, prot1 & PAGE_RWX);
+                       host_page_size, prot1 & PAGE_RWX);
         if (ret != 0)
             goto error;
-        host_start += qemu_host_page_size;
+        host_start += host_page_size;
     }
     if (end < host_end) {
         prot1 = target_prot;
         for (addr = end; addr < host_end; addr += TARGET_PAGE_SIZE) {
             prot1 |= page_get_flags(addr);
         }
-        ret = mprotect(g2h_untagged(host_end - qemu_host_page_size),
-                       qemu_host_page_size, prot1 & PAGE_RWX);
+        ret = mprotect(g2h_untagged(host_end - host_page_size),
+                       host_page_size, prot1 & PAGE_RWX);
         if (ret != 0)
             goto error;
-        host_end -= qemu_host_page_size;
+        host_end -= host_page_size;
     }
 
     /* handle the pages in the middle */
-- 
2.45.1
Re: [PATCH 15/17] bsd-user: target_mprotect: use helper host_page_size local
Posted by Richard Henderson 3 months, 3 weeks ago
On 8/3/24 09:56, Warner Losh wrote:
> Use helper variable for host_page_size. Linux-user uses a similar helper
> to make the code smaller after the multi-page-size migration.
> 
> Signed-off-by: Warner Losh<imp@bsdimp.com>
> ---
>   bsd-user/mmap.c | 15 ++++++++-------
>   1 file changed, 8 insertions(+), 7 deletions(-)

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

r~