[PATCH v2 04/10] hugetlbfs: hugetlb_vmtruncate_list() needs to take a range to delete

Path	csiph.com!aioe.org!bofh.it!news.nic.it!robomod
From	Mike Kravetz <mike.kravetz@oracle.com>
Newsgroups	linux.kernel
Subject	[PATCH v2 04/10] hugetlbfs: hugetlb_vmtruncate_list() needs to take a range to delete
Date	Thu, 09 Jul 2015 02:30:02 +0200
Message-ID	<pK7SW-1AK-17@gated-at.bofh.it> (permalink)
References	<pK7SW-1AK-7@gated-at.bofh.it>
X-Original-To	linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-api@vger.kernel.org
X-Mailer	git-send-email 2.1.0
X-Source-IP	userv0021.oracle.com [156.151.31.71]
Sender	robomod@news.nic.it
List-ID	<linux-kernel.vger.kernel.org>
X-Mailing-List	linux-kernel@vger.kernel.org
Approved	robomod@news.nic.it
Lines	78
Organization	linux.* mail to news gateway
X-Original-Cc	Dave Hansen <dave.hansen@linux.intel.com>, Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>, David Rientjes <rientjes@google.com>, Hugh Dickins <hughd@google.com>, Davidlohr Bueso <dave@stgolabs.net>, Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com>, Hillf Danton <hillf.zj@alibaba-inc.com>, Christoph Hellwig <hch@infradead.org>, Andrew Morton <akpm@linux-foundation.org>, Michal Hocko <mhocko@suse.cz>, Mike Kravetz <mike.kravetz@oracle.com>
X-Original-Date	Wed, 8 Jul 2015 17:21:35 -0700
X-Original-Message-ID	<1436401301-18839-5-git-send-email-mike.kravetz@oracle.com>
X-Original-References	<1436401301-18839-1-git-send-email-mike.kravetz@oracle.com>
X-Original-Sender	linux-kernel-owner@vger.kernel.org
Xref	aioe.org linux.kernel:1180331

Show key headers only | View raw

fallocate hole punch will want to unmap a specific range of pages.
Modify the existing hugetlb_vmtruncate_list() routine to take a
start/end range.  If end is 0, this indicates all pages after start
should be unmapped.  This is the same as the existing truncate
functionality.  Modify existing callers to add 0 as end of range.

Since the routine will be used in hole punch as well as truncate
operations, it is more appropriately renamed to hugetlb_vmdelete_list().

Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
---
 fs/hugetlbfs/inode.c | 25 ++++++++++++++++++-------
 1 file changed, 18 insertions(+), 7 deletions(-)

diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index 0cf74df..ed40f56 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -349,11 +349,15 @@ static void hugetlbfs_evict_inode(struct inode *inode)
 }
 
 static inline void
-hugetlb_vmtruncate_list(struct rb_root *root, pgoff_t pgoff)
+hugetlb_vmdelete_list(struct rb_root *root, pgoff_t start, pgoff_t end)
 {
 	struct vm_area_struct *vma;
 
-	vma_interval_tree_foreach(vma, root, pgoff, ULONG_MAX) {
+	/*
+	 * end == 0 indicates that the entire range after
+	 * start should be unmapped.
+	 */
+	vma_interval_tree_foreach(vma, root, start, end ? end : ULONG_MAX) {
 		unsigned long v_offset;
 
 		/*
@@ -362,13 +366,20 @@ hugetlb_vmtruncate_list(struct rb_root *root, pgoff_t pgoff)
 		 * which overlap the truncated area starting at pgoff,
 		 * and no vma on a 32-bit arch can span beyond the 4GB.
 		 */
-		if (vma->vm_pgoff < pgoff)
-			v_offset = (pgoff - vma->vm_pgoff) << PAGE_SHIFT;
+		if (vma->vm_pgoff < start)
+			v_offset = (start - vma->vm_pgoff) << PAGE_SHIFT;
 		else
 			v_offset = 0;
 
-		unmap_hugepage_range(vma, vma->vm_start + v_offset,
-				     vma->vm_end, NULL);
+		if (end) {
+			end = ((end - start) << PAGE_SHIFT) +
+			       vma->vm_start + v_offset;
+			if (end > vma->vm_end)
+				end = vma->vm_end;
+		} else
+			end = vma->vm_end;
+
+		unmap_hugepage_range(vma, vma->vm_start + v_offset, end, NULL);
 	}
 }
 
@@ -384,7 +395,7 @@ static int hugetlb_vmtruncate(struct inode *inode, loff_t offset)
 	i_size_write(inode, offset);
 	i_mmap_lock_write(mapping);
 	if (!RB_EMPTY_ROOT(&mapping->i_mmap))
-		hugetlb_vmtruncate_list(&mapping->i_mmap, pgoff);
+		hugetlb_vmdelete_list(&mapping->i_mmap, pgoff, 0);
 	i_mmap_unlock_write(mapping);
 	truncate_hugepages(inode, offset);
 	return 0;
-- 
2.1.0

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Back to linux.kernel | Previous | Next | Find similar | Unroll thread

Thread

[PATCH v2 04/10] hugetlbfs: hugetlb_vmtruncate_list() needs to take a range to delete Mike Kravetz <mike.kravetz@oracle.com> - 2015-07-09 02:30 +0200

csiph-web