[Xenomai] [PATCH 1/3] ipipe: Factor out ipipe_pin_vma

[Jan Kiszka]

Will be used for pinning during mprotect as well.

Signed-off-by: Jan Kiszka <jan.kis...@siemens.com>
---
 include/linux/ipipe.h |    1 +
 mm/memory.c           |   43 +++++++++++++++++++++++++------------------
 2 files changed, 26 insertions(+), 18 deletions(-)

diff --git a/include/linux/ipipe.h b/include/linux/ipipe.h
index fb0789e..48f93bd 100644
--- a/include/linux/ipipe.h
+++ b/include/linux/ipipe.h
@@ -647,6 +647,7 @@ int ipipe_set_ptd(int key,
 void *ipipe_get_ptd(int key);
 
 int ipipe_disable_ondemand_mappings(struct task_struct *tsk);
+int ipipe_pin_vma(struct mm_struct *mm, struct vm_area_struct *vma);
 
 static inline void ipipe_nmi_enter(void)
 {
diff --git a/mm/memory.c b/mm/memory.c
index 949d965..18a59619 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -3903,13 +3903,31 @@ static inline int ipipe_pin_pud_range(struct mm_struct 
*mm, pgd_t *pgd,
        return 0;
 }
 
-int ipipe_disable_ondemand_mappings(struct task_struct *tsk)
+int ipipe_pin_vma(struct mm_struct *mm, struct vm_area_struct *vma)
 {
        unsigned long addr, next, end;
+       pgd_t *pgd;
+
+       addr = vma->vm_start;
+       end = vma->vm_end;
+
+       pgd = pgd_offset(mm, addr);
+       do {
+               next = pgd_addr_end(addr, end);
+               if (pgd_none_or_clear_bad(pgd))
+                       continue;
+               if (ipipe_pin_pud_range(mm, pgd, vma, addr, next))
+                       return -ENOMEM;
+       } while (pgd++, addr = next, addr != end);
+
+       return 0;
+}
+
+int ipipe_disable_ondemand_mappings(struct task_struct *tsk)
+{
        struct vm_area_struct *vma;
        struct mm_struct *mm;
        int result = 0;
-       pgd_t *pgd;
 
        mm = get_task_mm(tsk);
        if (!mm)
@@ -3920,23 +3938,12 @@ int ipipe_disable_ondemand_mappings(struct task_struct 
*tsk)
                goto done_mm;
 
        for (vma = mm->mmap; vma; vma = vma->vm_next) {
-               if (!is_cow_mapping(vma->vm_flags)
-                   || !(vma->vm_flags & VM_WRITE))
-                       continue;
-
-               addr = vma->vm_start;
-               end = vma->vm_end;
-
-               pgd = pgd_offset(mm, addr);
-               do {
-                       next = pgd_addr_end(addr, end);
-                       if (pgd_none_or_clear_bad(pgd))
-                               continue;
-                       if (ipipe_pin_pud_range(mm, pgd, vma, addr, next)) {
-                               result = -ENOMEM;
+               if (is_cow_mapping(vma->vm_flags) &&
+                   (vma->vm_flags & VM_WRITE)) {
+                       result = ipipe_pin_vma(mm, vma);
+                       if (result < 0)
                                goto done_mm;
-                       }
-               } while (pgd++, addr = next, addr != end);
+               }
        }
        set_bit(MMF_VM_PINNED, &mm->flags);
 
-- 
1.7.3.4


_______________________________________________
Xenomai mailing list
Xenomai@xenomai.org
http://www.xenomai.org/mailman/listinfo/xenomai