diff options
| -rw-r--r-- | Documentation/vm/unevictable-lru.txt | 26 | ||||
| -rw-r--r-- | mm/internal.h | 2 | ||||
| -rw-r--r-- | mm/mlock.c | 12 | ||||
| -rw-r--r-- | mm/mmap.c | 4 |
4 files changed, 17 insertions, 27 deletions
diff --git a/Documentation/vm/unevictable-lru.txt b/Documentation/vm/unevictable-lru.txt index 744f82f86c58..86cb4624fc5a 100644 --- a/Documentation/vm/unevictable-lru.txt +++ b/Documentation/vm/unevictable-lru.txt @@ -317,7 +317,7 @@ If the VMA passes some filtering as described in "Filtering Special Vmas" below, mlock_fixup() will attempt to merge the VMA with its neighbors or split off a subset of the VMA if the range does not cover the entire VMA. Once the VMA has been merged or split or neither, mlock_fixup() will call -__mlock_vma_pages_range() to fault in the pages via get_user_pages() and to +populate_vma_page_range() to fault in the pages via get_user_pages() and to mark the pages as mlocked via mlock_vma_page(). Note that the VMA being mlocked might be mapped with PROT_NONE. In this case, @@ -327,7 +327,7 @@ fault path or in vmscan. Also note that a page returned by get_user_pages() could be truncated or migrated out from under us, while we're trying to mlock it. To detect this, -__mlock_vma_pages_range() checks page_mapping() after acquiring the page lock. +populate_vma_page_range() checks page_mapping() after acquiring the page lock. If the page is still associated with its mapping, we'll go ahead and call mlock_vma_page(). If the mapping is gone, we just unlock the page and move on. In the worst case, this will result in a page mapped in a VM_LOCKED VMA @@ -392,7 +392,7 @@ ignored for munlock. If the VMA is VM_LOCKED, mlock_fixup() again attempts to merge or split off the specified range. The range is then munlocked via the function -__mlock_vma_pages_range() - the same function used to mlock a VMA range - +populate_vma_page_range() - the same function used to mlock a VMA range - passing a flag to indicate that munlock() is being performed. Because the VMA access protections could have been changed to PROT_NONE after @@ -402,7 +402,7 @@ get_user_pages() was enhanced to accept a flag to ignore the permissions when fetching the pages - all of which should be resident as a result of previous mlocking. -For munlock(), __mlock_vma_pages_range() unlocks individual pages by calling +For munlock(), populate_vma_page_range() unlocks individual pages by calling munlock_vma_page(). munlock_vma_page() unconditionally clears the PG_mlocked flag using TestClearPageMlocked(). As with mlock_vma_page(), munlock_vma_page() use the Test*PageMlocked() function to handle the case where @@ -463,21 +463,11 @@ populate the page table. To mlock a range of memory under the unevictable/mlock infrastructure, the mmap() handler and task address space expansion functions call -mlock_vma_pages_range() specifying the vma and the address range to mlock. -mlock_vma_pages_range() filters VMAs like mlock_fixup(), as described above in -"Filtering Special VMAs". It will clear the VM_LOCKED flag, which will have -already been set by the caller, in filtered VMAs. Thus these VMA's need not be -visited for munlock when the region is unmapped. - -For "normal" VMAs, mlock_vma_pages_range() calls __mlock_vma_pages_range() to -fault/allocate the pages and mlock them. Again, like mlock_fixup(), -mlock_vma_pages_range() downgrades the mmap semaphore to read mode before -attempting to fault/allocate and mlock the pages and "upgrades" the semaphore -back to write mode before returning. - -The callers of mlock_vma_pages_range() will have already added the memory range +populate_vma_page_range() specifying the vma and the address range to mlock. + +The callers of populate_vma_page_range() will have already added the memory range to be mlocked to the task's "locked_vm". To account for filtered VMAs, -mlock_vma_pages_range() returns the number of pages NOT mlocked. All of the +populate_vma_page_range() returns the number of pages NOT mlocked. All of the callers then subtract a non-negative return value from the task's locked_vm. A negative return value represent an error - for example, from get_user_pages() attempting to fault in a VMA with PROT_NONE access. In this case, we leave the diff --git a/mm/internal.h b/mm/internal.h index a96da5b0029d..7df78a5269f3 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -240,7 +240,7 @@ void __vma_link_list(struct mm_struct *mm, struct vm_area_struct *vma, struct vm_area_struct *prev, struct rb_node *rb_parent); #ifdef CONFIG_MMU -extern long __mlock_vma_pages_range(struct vm_area_struct *vma, +extern long populate_vma_page_range(struct vm_area_struct *vma, unsigned long start, unsigned long end, int *nonblocking); extern void munlock_vma_pages_range(struct vm_area_struct *vma, unsigned long start, unsigned long end); diff --git a/mm/mlock.c b/mm/mlock.c index f756e28b33fc..9d0f3cd716c5 100644 --- a/mm/mlock.c +++ b/mm/mlock.c @@ -206,13 +206,13 @@ out: } /** - * __mlock_vma_pages_range() - mlock a range of pages in the vma. + * populate_vma_page_range() - populate a range of pages in the vma. * @vma: target vma * @start: start address * @end: end address * @nonblocking: * - * This takes care of making the pages present too. + * This takes care of mlocking the pages too if VM_LOCKED is set. * * return 0 on success, negative error code on error. * @@ -224,7 +224,7 @@ out: * If @nonblocking is non-NULL, it must held for read only and may be * released. If it's released, *@nonblocking will be set to 0. */ -long __mlock_vma_pages_range(struct vm_area_struct *vma, +long populate_vma_page_range(struct vm_area_struct *vma, unsigned long start, unsigned long end, int *nonblocking) { struct mm_struct *mm = vma->vm_mm; @@ -596,7 +596,7 @@ success: /* * vm_flags is protected by the mmap_sem held in write mode. * It's okay if try_to_unmap_one unmaps a page just after we - * set VM_LOCKED, __mlock_vma_pages_range will bring it back. + * set VM_LOCKED, populate_vma_page_range will bring it back. */ if (lock) @@ -702,11 +702,11 @@ int __mm_populate(unsigned long start, unsigned long len, int ignore_errors) if (nstart < vma->vm_start) nstart = vma->vm_start; /* - * Now fault in a range of pages. __mlock_vma_pages_range() + * Now fault in a range of pages. populate_vma_page_range() * double checks the vma flags, so that it won't mlock pages * if the vma was already munlocked. */ - ret = __mlock_vma_pages_range(vma, nstart, nend, &locked); + ret = populate_vma_page_range(vma, nstart, nend, &locked); if (ret < 0) { if (ignore_errors) { ret = 0; diff --git a/mm/mmap.c b/mm/mmap.c index 9ec50a368634..06a6076c92e5 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -2316,7 +2316,7 @@ find_extend_vma(struct mm_struct *mm, unsigned long addr) if (!prev || expand_stack(prev, addr)) return NULL; if (prev->vm_flags & VM_LOCKED) - __mlock_vma_pages_range(prev, addr, prev->vm_end, NULL); + populate_vma_page_range(prev, addr, prev->vm_end, NULL); return prev; } #else @@ -2351,7 +2351,7 @@ find_extend_vma(struct mm_struct *mm, unsigned long addr) if (expand_stack(vma, addr)) return NULL; if (vma->vm_flags & VM_LOCKED) - __mlock_vma_pages_range(vma, addr, start, NULL); + populate_vma_page_range(vma, addr, start, NULL); return vma; } #endif |