This first part contains the additions to the existing infrastructure
needed to implement the new interfaces used in the rest of the patch.
In exec.c, page_check_range() has been added to take an address and a
size and and check to see if it is contained in a valid page that
belongs to the target. A flag is passed t indicate wether read or write
access should be checked.
In qemu.h, the access_ok macro has been given a real implemention, and
implementations of copy_from_user() and copy_to_user() have been added.
Stuart
Stuart R. Anderson [EMAIL PROTECTED]
Network & Software Engineering http://www.netsweng.com/
1024D/37A79149: 0791 D3B8 9A4C 2CDC A31F
BD03 0A62 E534 37A7 9149Index: qemu/exec.c
===================================================================
--- qemu.orig/exec.c 2007-08-07 21:44:10.000000000 -0400
+++ qemu/exec.c 2007-08-07 21:44:16.000000000 -0400
@@ -1862,6 +1862,29 @@
spin_unlock(&tb_lock);
}
+int page_check_range(target_ulong start, target_ulong len, int flags)
+{
+ PageDesc *p;
+ target_ulong end;
+ target_ulong addr;
+
+ end = TARGET_PAGE_ALIGN(start+len); /* must do before we loose bits in the
next step */
+ start = start & TARGET_PAGE_MASK;
+
+ if( end < start ) return -1; /* we've wrapped around */
+ for(addr = start; addr < end; addr += TARGET_PAGE_SIZE) {
+ p = page_find(addr >> TARGET_PAGE_BITS);
+ if( !p ) return -1;
+ if( !(p->flags & PAGE_VALID) ) return -1;
+
+ if (!(p->flags & PAGE_READ) &&
+ (flags & PAGE_READ) ) return -1;
+ if (!(p->flags & PAGE_WRITE) &&
+ (flags & PAGE_WRITE) ) return -1;
+ }
+ return 0;
+}
+
/* called from signal handler: invalidate the code and unprotect the
page. Return TRUE if the fault was succesfully handled. */
int page_unprotect(target_ulong address, unsigned long pc, void *puc)
Index: qemu/cpu-all.h
===================================================================
--- qemu.orig/cpu-all.h 2007-08-07 21:44:10.000000000 -0400
+++ qemu/cpu-all.h 2007-08-07 21:44:16.000000000 -0400
@@ -691,6 +691,7 @@
int page_get_flags(target_ulong address);
void page_set_flags(target_ulong start, target_ulong end, int flags);
void page_unprotect_range(target_ulong data, target_ulong data_size);
+int page_check_range(target_ulong start, target_ulong len, int flags);
CPUState *cpu_copy(CPUState *env);
Index: qemu/linux-user/qemu.h
===================================================================
--- qemu.orig/linux-user/qemu.h 2007-08-07 21:44:10.000000000 -0400
+++ qemu/linux-user/qemu.h 2007-08-08 17:54:18.000000000 -0400
@@ -171,7 +171,8 @@
#define VERIFY_READ 0
#define VERIFY_WRITE 1
-#define access_ok(type,addr,size) (1)
+#define access_ok(type,addr,size) \
+
(page_check_range((target_ulong)addr,size,(type==VERIFY_READ)?PAGE_READ:PAGE_WRITE)==0)
/* NOTE get_user and put_user use host addresses. */
#define __put_user(x,ptr)\
@@ -238,6 +239,26 @@
__ret;\
})
+#define copy_from_user(hptr, gptr, len) \
+({ \
+ int __cfu_ret=0;\
+ if( access_ok(VERIFY_READ, gptr, (len) ) )\
+ memcpy(hptr,gptr,(len)); \
+ else \
+ __cfu_ret=1;\
+ __cfu_ret; \
+})
+
+#define copy_to_user(gptr, hptr, len) \
+({ \
+ int __ctu_ret=0;\
+ if( access_ok(VERIFY_WRITE, gptr, (len)) )\
+ memcpy(gptr,hptr,(len)); \
+ else \
+ __ctu_ret=1;\
+ __ctu_ret; \
+})
+
/* Functions for accessing guest memory. The tget and tput functions
read/write single values, byteswapping as neccessary. The lock_user
gets a pointer to a contiguous area of guest memory, but does not perform
