projects
/
pintos-anon
/ blobdiff
commit
grep
author
committer
pickaxe
?
search:
re
summary
|
shortlog
|
log
|
commit
|
commitdiff
|
tree
raw
|
inline
| side by side
Comment.
[pintos-anon]
/
src
/
userprog
/
pagedir.c
diff --git
a/src/userprog/pagedir.c
b/src/userprog/pagedir.c
index 937f433da030505e701d00f7a9bb8a15feb49dcb..3f0e9fb47c1217c8bbe0266f8a5b6b7a9e130e0e 100644
(file)
--- a/
src/userprog/pagedir.c
+++ b/
src/userprog/pagedir.c
@@
-187,6
+187,11
@@
pagedir_activate (uint32_t *pd)
{
if (pd == NULL)
pd = base_page_dir;
{
if (pd == NULL)
pd = base_page_dir;
+
+ /* Store the physical address of the page directory into CR3
+ aka PDBR (page directory base register). This activates our
+ new page tables immediately. See [IA32-v2a] "MOV--Move
+ to/from Control Registers" and [IA32-v3] 3.7.5. */
asm volatile ("movl %0,%%cr3" :: "r" (vtop (pd)));
}
asm volatile ("movl %0,%%cr3" :: "r" (vtop (pd)));
}
@@
-196,6
+201,9
@@
active_pd (void)
{
uint32_t *pd;
{
uint32_t *pd;
+ /* Copy CR3, the page directory base register (PDBR), into `pd'
+ for us to examine. See [IA32-v2a] "MOV--Move to/from
+ Control Registers" and [IA32-v3] 3.7.5. */
asm ("movl %%cr3,%0" : "=r" (pd));
return pd;
}
asm ("movl %%cr3,%0" : "=r" (pd));
return pd;
}