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-rw-r--r--fs/proc/mem.c241
1 files changed, 142 insertions, 99 deletions
diff --git a/fs/proc/mem.c b/fs/proc/mem.c
index ae043bb0a..f44bd7fbc 100644
--- a/fs/proc/mem.c
+++ b/fs/proc/mem.c
@@ -13,6 +13,7 @@
#include <asm/page.h>
#include <asm/segment.h>
#include <asm/io.h>
+#include <asm/pgtable.h>
/*
* mem_write isn't really a good idea right now. It needs
@@ -24,42 +25,56 @@
static int mem_read(struct inode * inode, struct file * file,char * buf, int count)
{
- unsigned long addr, pid, cr3;
+ pgd_t *page_dir;
+ pmd_t *page_middle;
+ pte_t pte;
+ char * page;
+ struct task_struct * tsk;
+ unsigned long addr, pid;
char *tmp;
- unsigned long pte, page;
int i;
if (count < 0)
return -EINVAL;
pid = inode->i_ino;
pid >>= 16;
- cr3 = 0;
+ tsk = NULL;
for (i = 1 ; i < NR_TASKS ; i++)
if (task[i] && task[i]->pid == pid) {
- cr3 = task[i]->tss.cr3;
+ tsk = task[i];
break;
}
- if (!cr3)
+ if (!tsk)
return -EACCES;
addr = file->f_pos;
tmp = buf;
while (count > 0) {
if (current->signal & ~current->blocked)
break;
- pte = *PAGE_DIR_OFFSET(cr3,addr);
- if (!(pte & PAGE_PRESENT))
+ page_dir = pgd_offset(tsk,addr);
+ if (pgd_none(*page_dir))
break;
- pte &= PAGE_MASK;
- pte += PAGE_PTR(addr);
- page = *(unsigned long *) pte;
- if (!(page & 1))
+ if (pgd_bad(*page_dir)) {
+ printk("Bad page dir entry %08lx\n", pgd_val(*page_dir));
+ pgd_clear(page_dir);
break;
- page &= PAGE_MASK;
- page += addr & ~PAGE_MASK;
+ }
+ page_middle = pmd_offset(page_dir,addr);
+ if (pmd_none(*page_middle))
+ break;
+ if (pmd_bad(*page_middle)) {
+ printk("Bad page middle entry %08lx\n", pmd_val(*page_middle));
+ pmd_clear(page_middle);
+ break;
+ }
+ pte = *pte_offset(page_middle,addr);
+ if (!pte_present(pte))
+ break;
+ page = (char *) pte_page(pte) + (addr & ~PAGE_MASK);
i = PAGE_SIZE-(addr & ~PAGE_MASK);
if (i > count)
i = count;
- memcpy_tofs(tmp,(void *) page,i);
+ memcpy_tofs(tmp, page, i);
addr += i;
tmp += i;
count -= i;
@@ -72,9 +87,13 @@ static int mem_read(struct inode * inode, struct file * file,char * buf, int cou
static int mem_write(struct inode * inode, struct file * file,char * buf, int count)
{
- unsigned long addr, pid, cr3;
+ pgd_t *page_dir;
+ pmd_t *page_middle;
+ pte_t pte;
+ char * page;
+ struct task_struct * tsk;
+ unsigned long addr, pid;
char *tmp;
- unsigned long pte, page;
int i;
if (count < 0)
@@ -82,36 +101,44 @@ static int mem_write(struct inode * inode, struct file * file,char * buf, int co
addr = file->f_pos;
pid = inode->i_ino;
pid >>= 16;
- cr3 = 0;
+ tsk = NULL;
for (i = 1 ; i < NR_TASKS ; i++)
if (task[i] && task[i]->pid == pid) {
- cr3 = task[i]->tss.cr3;
+ tsk = task[i];
break;
}
- if (!cr3)
+ if (!tsk)
return -EACCES;
tmp = buf;
while (count > 0) {
if (current->signal & ~current->blocked)
break;
- pte = *PAGE_DIR_OFFSET(cr3,addr);
- if (!(pte & PAGE_PRESENT))
+ page_dir = pgd_offset(tsk,addr);
+ if (pgd_none(*page_dir))
+ break;
+ if (pgd_bad(*page_dir)) {
+ printk("Bad page dir entry %08lx\n", pgd_val(*page_dir));
+ pgd_clear(page_dir);
+ break;
+ }
+ page_middle = pmd_offset(page_dir,addr);
+ if (pmd_none(*page_middle))
break;
- pte &= PAGE_MASK;
- pte += PAGE_PTR(addr);
- page = *(unsigned long *) pte;
- if (!(page & PAGE_PRESENT))
+ if (pmd_bad(*page_middle)) {
+ printk("Bad page middle entry %08lx\n", pmd_val(*page_middle));
+ pmd_clear(page_middle);
break;
- if (!(page & 2)) {
- do_wp_page(0,addr,current,0);
- continue;
}
- page &= PAGE_MASK;
- page += addr & ~PAGE_MASK;
+ pte = *pte_offset(page_middle,addr);
+ if (!pte_present(pte))
+ break;
+ if (!pte_write(pte))
+ break;
+ page = (char *) pte_page(pte) + (addr & ~PAGE_MASK);
i = PAGE_SIZE-(addr & ~PAGE_MASK);
if (i > count)
i = count;
- memcpy_fromfs((void *) page,tmp,i);
+ memcpy_fromfs(page, tmp, i);
addr += i;
tmp += i;
count -= i;
@@ -140,92 +167,108 @@ static int mem_lseek(struct inode * inode, struct file * file, off_t offset, int
}
}
-int
-mem_mmap(struct inode * inode, struct file * file,
+/*
+ * This isn't really reliable by any means..
+ */
+int mem_mmap(struct inode * inode, struct file * file,
struct vm_area_struct * vma)
{
- unsigned long *src_table, *dest_table, stmp, dtmp, cr3;
- struct vm_area_struct *src_vma = 0;
- int i;
-
- /* Get the source's task information */
+ struct task_struct *tsk;
+ pgd_t *src_dir, *dest_dir;
+ pmd_t *src_middle, *dest_middle;
+ pte_t *src_table, *dest_table;
+ unsigned long stmp, dtmp;
+ struct vm_area_struct *src_vma = NULL;
+ int i;
- cr3 = 0;
- for (i = 1 ; i < NR_TASKS ; i++)
- if (task[i] && task[i]->pid == (inode->i_ino >> 16)) {
- cr3 = task[i]->tss.cr3;
- src_vma = task[i]->mm->mmap;
- break;
- }
+ /* Get the source's task information */
- if (!cr3)
- return -EACCES;
+ tsk = NULL;
+ for (i = 1 ; i < NR_TASKS ; i++)
+ if (task[i] && task[i]->pid == (inode->i_ino >> 16)) {
+ tsk = task[i];
+ break;
+ }
-/* Ensure that we have a valid source area. (Has to be mmap'ed and
- have valid page information.) We can't map shared memory at the
- moment because working out the vm_area_struct & nattach stuff isn't
- worth it. */
+ if (!tsk)
+ return -EACCES;
- stmp = vma->vm_offset;
- while (stmp < vma->vm_offset + (vma->vm_end - vma->vm_start)) {
- while (src_vma && stmp > src_vma->vm_end)
- src_vma = src_vma->vm_next;
- if (!src_vma || (src_vma->vm_flags & VM_SHM))
- return -EINVAL;
+ /* Ensure that we have a valid source area. (Has to be mmap'ed and
+ have valid page information.) We can't map shared memory at the
+ moment because working out the vm_area_struct & nattach stuff isn't
+ worth it. */
- src_table = PAGE_DIR_OFFSET(cr3, stmp);
- if (!*src_table)
- return -EINVAL;
- src_table = (unsigned long *)((*src_table & PAGE_MASK) + PAGE_PTR(stmp));
- if (!*src_table)
- return -EINVAL;
+ src_vma = tsk->mm->mmap;
+ stmp = vma->vm_offset;
+ while (stmp < vma->vm_offset + (vma->vm_end - vma->vm_start)) {
+ while (src_vma && stmp > src_vma->vm_end)
+ src_vma = src_vma->vm_next;
+ if (!src_vma || (src_vma->vm_flags & VM_SHM))
+ return -EINVAL;
- if (stmp < src_vma->vm_start) {
- if (!(src_vma->vm_flags & VM_GROWSDOWN))
- return -EINVAL;
- if (src_vma->vm_end - stmp > current->rlim[RLIMIT_STACK].rlim_cur)
- return -EINVAL;
- }
- stmp += PAGE_SIZE;
- }
+ src_dir = pgd_offset(tsk, stmp);
+ if (pgd_none(*src_dir))
+ return -EINVAL;
+ if (pgd_bad(*src_dir)) {
+ printk("Bad source page dir entry %08lx\n", pgd_val(*src_dir));
+ return -EINVAL;
+ }
+ src_middle = pmd_offset(src_dir, stmp);
+ if (pmd_none(*src_middle))
+ return -EINVAL;
+ if (pmd_bad(*src_middle)) {
+ printk("Bad source page middle entry %08lx\n", pmd_val(*src_middle));
+ return -EINVAL;
+ }
+ src_table = pte_offset(src_middle, stmp);
+ if (pte_none(*src_table))
+ return -EINVAL;
- src_vma = task[i]->mm->mmap;
- stmp = vma->vm_offset;
- dtmp = vma->vm_start;
+ if (stmp < src_vma->vm_start) {
+ if (!(src_vma->vm_flags & VM_GROWSDOWN))
+ return -EINVAL;
+ if (src_vma->vm_end - stmp > current->rlim[RLIMIT_STACK].rlim_cur)
+ return -EINVAL;
+ }
+ stmp += PAGE_SIZE;
+ }
- while (dtmp < vma->vm_end) {
- while (src_vma && stmp > src_vma->vm_end)
- src_vma = src_vma->vm_next;
+ src_vma = tsk->mm->mmap;
+ stmp = vma->vm_offset;
+ dtmp = vma->vm_start;
- src_table = PAGE_DIR_OFFSET(cr3, stmp);
- src_table = (unsigned long *)((*src_table & PAGE_MASK) + PAGE_PTR(stmp));
+ while (dtmp < vma->vm_end) {
+ while (src_vma && stmp > src_vma->vm_end)
+ src_vma = src_vma->vm_next;
- dest_table = PAGE_DIR_OFFSET(current->tss.cr3, dtmp);
+ src_dir = pgd_offset(tsk, stmp);
+ src_middle = pmd_offset(src_dir, stmp);
+ src_table = pte_offset(src_middle, stmp);
- if (!*dest_table) {
- *dest_table = get_free_page(GFP_KERNEL);
- if (!*dest_table) { oom(current); *dest_table=BAD_PAGE; }
- else *dest_table |= PAGE_TABLE;
- }
-
- dest_table = (unsigned long *)((*dest_table & PAGE_MASK) + PAGE_PTR(dtmp));
+ dest_dir = pgd_offset(current, dtmp);
+ dest_middle = pmd_alloc(dest_dir, dtmp);
+ if (!dest_middle)
+ return -ENOMEM;
+ dest_table = pte_alloc(dest_middle, dtmp);
+ if (!dest_table)
+ return -ENOMEM;
- if (!(*src_table & PAGE_PRESENT))
- do_no_page(src_vma, stmp, PAGE_PRESENT);
+ if (!pte_present(*src_table))
+ do_no_page(src_vma, stmp, 1);
- if ((vma->vm_flags & VM_WRITE) && !(*src_table & PAGE_RW))
- do_wp_page(src_vma, stmp, PAGE_RW | PAGE_PRESENT);
+ if ((vma->vm_flags & VM_WRITE) && !pte_write(*src_table))
+ do_wp_page(src_vma, stmp, 1);
- *src_table |= PAGE_DIRTY;
- *dest_table = *src_table;
- mem_map[MAP_NR(*src_table)]++;
+ *src_table = pte_mkdirty(*src_table);
+ *dest_table = *src_table;
+ mem_map[MAP_NR(pte_page(*src_table))]++;
- stmp += PAGE_SIZE;
- dtmp += PAGE_SIZE;
- }
+ stmp += PAGE_SIZE;
+ dtmp += PAGE_SIZE;
+ }
- invalidate();
- return 0;
+ invalidate();
+ return 0;
}
static struct file_operations proc_mem_operations = {
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-09 15:41:07 +0000