diff options
author | Brice Goglin <Brice.Goglin@inria.fr> | 2008-10-19 05:27:16 +0200 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-10-20 17:52:33 +0200 |
commit | 2f007e74bb85b9fc4eab28524052161703300f1a (patch) | |
tree | 8fa77e687aa5fd807767484bdafcce86e46a56af /mm | |
parent | mm: stop returning -ENOENT from sys_move_pages() if nothing got migrated (diff) | |
download | linux-2f007e74bb85b9fc4eab28524052161703300f1a.tar.xz linux-2f007e74bb85b9fc4eab28524052161703300f1a.zip |
mm: don't vmalloc a huge page_to_node array for do_pages_stat()
do_pages_stat() does not need any page_to_node entry for real. Just pass
the pointers to the user-space page address array and to the user-space
status array, and have do_pages_stat() traverse the former and fill the
latter directly.
Signed-off-by: Brice Goglin <Brice.Goglin@inria.fr>
Acked-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
-rw-r--r-- | mm/migrate.c | 40 |
1 files changed, 25 insertions, 15 deletions
diff --git a/mm/migrate.c b/mm/migrate.c index f233519f0453..a4c29081ebce 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -906,25 +906,33 @@ set_status: } /* - * Determine the nodes of a list of pages. The addr in the pm array - * must have been set to the virtual address of which we want to determine - * the node number. + * Determine the nodes of an array of pages and store it in an array of status. */ -static int do_pages_stat(struct mm_struct *mm, struct page_to_node *pm) +static int do_pages_stat(struct mm_struct *mm, unsigned long nr_pages, + const void __user * __user *pages, + int __user *status) { + unsigned long i; + int err; + down_read(&mm->mmap_sem); - for ( ; pm->node != MAX_NUMNODES; pm++) { + for (i = 0; i < nr_pages; i++) { + const void __user *p; + unsigned long addr; struct vm_area_struct *vma; struct page *page; - int err; err = -EFAULT; - vma = find_vma(mm, pm->addr); + if (get_user(p, pages+i)) + goto out; + addr = (unsigned long) p; + + vma = find_vma(mm, addr); if (!vma) goto set_status; - page = follow_page(vma, pm->addr, 0); + page = follow_page(vma, addr, 0); err = PTR_ERR(page); if (IS_ERR(page)) @@ -937,11 +945,13 @@ static int do_pages_stat(struct mm_struct *mm, struct page_to_node *pm) err = page_to_nid(page); set_status: - pm->status = err; + put_user(err, status+i); } + err = 0; +out: up_read(&mm->mmap_sem); - return 0; + return err; } /* @@ -997,6 +1007,10 @@ asmlinkage long sys_move_pages(pid_t pid, unsigned long nr_pages, if (err) goto out2; + if (!nodes) { + err = do_pages_stat(mm, nr_pages, pages, status); + goto out2; + } task_nodes = cpuset_mems_allowed(task); @@ -1045,11 +1059,7 @@ asmlinkage long sys_move_pages(pid_t pid, unsigned long nr_pages, /* End marker */ pm[nr_pages].node = MAX_NUMNODES; - if (nodes) - err = do_move_pages(mm, pm, flags & MPOL_MF_MOVE_ALL); - else - err = do_pages_stat(mm, pm); - + err = do_move_pages(mm, pm, flags & MPOL_MF_MOVE_ALL); if (err >= 0) /* Return status information */ for (i = 0; i < nr_pages; i++) |