From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oi0-f44.google.com (mail-oi0-f44.google.com [209.85.218.44]) by kanga.kvack.org (Postfix) with ESMTP id 8E7CE6B006C for ; Thu, 16 Apr 2015 19:03:20 -0400 (EDT) Received: by oica37 with SMTP id a37so56464649oic.0 for ; Thu, 16 Apr 2015 16:03:20 -0700 (PDT) Received: from userp1040.oracle.com (userp1040.oracle.com. [156.151.31.81]) by mx.google.com with ESMTPS id x6si6488093oig.122.2015.04.16.16.03.19 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 16 Apr 2015 16:03:20 -0700 (PDT) From: Mike Kravetz Subject: [RFC PATCH 1/4] hugetlbfs: truncate_hugepages() takes a range of pages Date: Thu, 16 Apr 2015 16:02:55 -0700 Message-Id: <1429225378-22965-2-git-send-email-mike.kravetz@oracle.com> In-Reply-To: <1429225378-22965-1-git-send-email-mike.kravetz@oracle.com> References: <1429225378-22965-1-git-send-email-mike.kravetz@oracle.com> Sender: owner-linux-mm@kvack.org List-ID: To: linux-mm@kvack.org, linux-kernel@vger.kernel.org Cc: Dave Hansen , Naoya Horiguchi , David Rientjes , Hugh Dickins , Davidlohr Bueso , Aneesh Kumar , Mike Kravetz Modify truncate_hugepages() to take a range of pages (start, end) instead of simply start. If the value of end is -1, this indicates the end of the range is the end of the file. This functionality will be used for fallocate hole punching. Signed-off-by: Dave Hansen Signed-off-by: Mike Kravetz --- fs/hugetlbfs/inode.c | 25 +++++++++++++++++++++---- 1 file changed, 21 insertions(+), 4 deletions(-) diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c index c274aca..d5b67fd 100644 --- a/fs/hugetlbfs/inode.c +++ b/fs/hugetlbfs/inode.c @@ -324,11 +324,12 @@ static void truncate_huge_page(struct page *page) delete_from_page_cache(page); } -static void truncate_hugepages(struct inode *inode, loff_t lstart) +static void truncate_hugepages(struct inode *inode, loff_t lstart, loff_t lend) { struct hstate *h = hstate_inode(inode); struct address_space *mapping = &inode->i_data; const pgoff_t start = lstart >> huge_page_shift(h); + const pgoff_t end = lend >> huge_page_shift(h); struct pagevec pvec; pgoff_t next; int i, freed = 0; @@ -336,7 +337,19 @@ static void truncate_hugepages(struct inode *inode, loff_t lstart) pagevec_init(&pvec, 0); next = start; while (1) { - if (!pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) { + long lookup_nr = PAGEVEC_SIZE; + + /* + * Make sure to never grab more pages that we + * might possibly need. + */ + if (end - start < lookup_nr) + lookup_nr = end - start; + /* + * This pagevec_lookup() may return pages past 'end', + * so we must check for page->index > end. + */ + if (!pagevec_lookup(&pvec, mapping, next, lookup_nr)) { if (next == start) break; next = start; @@ -347,6 +360,10 @@ static void truncate_hugepages(struct inode *inode, loff_t lstart) struct page *page = pvec.pages[i]; lock_page(page); + if (page->index >= end) { + unlock_page(page); + break; + } if (page->index > next) next = page->index; ++next; @@ -364,7 +381,7 @@ static void hugetlbfs_evict_inode(struct inode *inode) { struct resv_map *resv_map; - truncate_hugepages(inode, 0); + truncate_hugepages(inode, 0, -1); resv_map = (struct resv_map *)inode->i_mapping->private_data; /* root inode doesn't have the resv_map, so we should check it */ if (resv_map) @@ -410,7 +427,7 @@ static int hugetlb_vmtruncate(struct inode *inode, loff_t offset) if (!RB_EMPTY_ROOT(&mapping->i_mmap)) hugetlb_vmtruncate_list(&mapping->i_mmap, pgoff); i_mmap_unlock_write(mapping); - truncate_hugepages(inode, offset); + truncate_hugepages(inode, offset, -1); return 0; } -- 2.1.0 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org