From patchwork Mon Nov 10 11:30:54 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luis Henriques X-Patchwork-Id: 408857 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) by ozlabs.org (Postfix) with ESMTP id F255D140174; Mon, 10 Nov 2014 22:39:31 +1100 (AEDT) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1XnnJe-0004OK-JT; Mon, 10 Nov 2014 11:39:26 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1XnnBP-00075I-S3 for kernel-team@lists.ubuntu.com; Mon, 10 Nov 2014 11:30:55 +0000 Received: from bl20-155-74.dsl.telepac.pt ([2.81.155.74] helo=localhost) by youngberry.canonical.com with esmtpsa (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1XnnBP-00012J-F3; Mon, 10 Nov 2014 11:30:55 +0000 From: Luis Henriques To: Miklos Szeredi Subject: [3.16.y-ckt extended stable] Patch "fuse: honour max_read and max_write in direct_io mode" has been added to staging queue Date: Mon, 10 Nov 2014 11:30:54 +0000 Message-Id: <1415619054-6793-1-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 2.1.0 X-Extended-Stable: 3.16 Cc: kernel-team@lists.ubuntu.com, Al Viro , Werner Baumann X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.14 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: kernel-team-bounces@lists.ubuntu.com This is a note to let you know that I have just added a patch titled fuse: honour max_read and max_write in direct_io mode to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.16.y-queue This patch is scheduled to be released in version 3.16.7-ckt1. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.16.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ------ From ad0f3236b95c392787cb8555aea5ee1c4d84f01e Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Wed, 24 Sep 2014 17:09:11 +0200 Subject: fuse: honour max_read and max_write in direct_io mode commit 2c80929c4c4d54e568b07ab85877d5fd38f4b02f upstream. The third argument of fuse_get_user_pages() "nbytesp" refers to the number of bytes a caller asked to pack into fuse request. This value may be lesser than capacity of fuse request or iov_iter. So fuse_get_user_pages() must ensure that *nbytesp won't grow. Now, when helper iov_iter_get_pages() performs all hard work of extracting pages from iov_iter, it can be done by passing properly calculated "maxsize" to the helper. The other caller of iov_iter_get_pages() (dio_refill_pages()) doesn't need this capability, so pass LONG_MAX as the maxsize argument here. Fixes: c9c37e2e6378 ("fuse: switch to iov_iter_get_pages()") Reported-by: Werner Baumann Tested-by: Maxim Patlasov Signed-off-by: Miklos Szeredi Signed-off-by: Al Viro Signed-off-by: Luis Henriques --- fs/direct-io.c | 2 +- fs/fuse/file.c | 1 + include/linux/uio.h | 2 +- mm/iov_iter.c | 14 +++++++++----- 4 files changed, 12 insertions(+), 7 deletions(-) -- 2.1.0 diff --git a/fs/direct-io.c b/fs/direct-io.c index c3116404ab49..e181b6b2e297 100644 --- a/fs/direct-io.c +++ b/fs/direct-io.c @@ -158,7 +158,7 @@ static inline int dio_refill_pages(struct dio *dio, struct dio_submit *sdio) { ssize_t ret; - ret = iov_iter_get_pages(sdio->iter, dio->pages, DIO_PAGES, + ret = iov_iter_get_pages(sdio->iter, dio->pages, LONG_MAX, DIO_PAGES, &sdio->from); if (ret < 0 && sdio->blocks_available && (dio->rw & WRITE)) { diff --git a/fs/fuse/file.c b/fs/fuse/file.c index 912061ac4baf..caa8d95b24e8 100644 --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -1305,6 +1305,7 @@ static int fuse_get_user_pages(struct fuse_req *req, struct iov_iter *ii, size_t start; ssize_t ret = iov_iter_get_pages(ii, &req->pages[req->num_pages], + *nbytesp - nbytes, req->max_pages - req->num_pages, &start); if (ret < 0) diff --git a/include/linux/uio.h b/include/linux/uio.h index 48d64e6ab292..290fbf0b6b8a 100644 --- a/include/linux/uio.h +++ b/include/linux/uio.h @@ -84,7 +84,7 @@ unsigned long iov_iter_alignment(const struct iov_iter *i); void iov_iter_init(struct iov_iter *i, int direction, const struct iovec *iov, unsigned long nr_segs, size_t count); ssize_t iov_iter_get_pages(struct iov_iter *i, struct page **pages, - unsigned maxpages, size_t *start); + size_t maxsize, unsigned maxpages, size_t *start); ssize_t iov_iter_get_pages_alloc(struct iov_iter *i, struct page ***pages, size_t maxsize, size_t *start); int iov_iter_npages(const struct iov_iter *i, int maxpages); diff --git a/mm/iov_iter.c b/mm/iov_iter.c index ab88dc0ea1d3..9a09f2034fcc 100644 --- a/mm/iov_iter.c +++ b/mm/iov_iter.c @@ -310,7 +310,7 @@ void iov_iter_init(struct iov_iter *i, int direction, EXPORT_SYMBOL(iov_iter_init); static ssize_t get_pages_iovec(struct iov_iter *i, - struct page **pages, unsigned maxpages, + struct page **pages, size_t maxsize, unsigned maxpages, size_t *start) { size_t offset = i->iov_offset; @@ -323,6 +323,8 @@ static ssize_t get_pages_iovec(struct iov_iter *i, len = iov->iov_len - offset; if (len > i->count) len = i->count; + if (len > maxsize) + len = maxsize; addr = (unsigned long)iov->iov_base + offset; len += *start = addr & (PAGE_SIZE - 1); if (len > maxpages * PAGE_SIZE) @@ -588,13 +590,15 @@ static unsigned long alignment_bvec(const struct iov_iter *i) } static ssize_t get_pages_bvec(struct iov_iter *i, - struct page **pages, unsigned maxpages, + struct page **pages, size_t maxsize, unsigned maxpages, size_t *start) { const struct bio_vec *bvec = i->bvec; size_t len = bvec->bv_len - i->iov_offset; if (len > i->count) len = i->count; + if (len > maxsize) + len = maxsize; /* can't be more than PAGE_SIZE */ *start = bvec->bv_offset + i->iov_offset; @@ -711,13 +715,13 @@ unsigned long iov_iter_alignment(const struct iov_iter *i) EXPORT_SYMBOL(iov_iter_alignment); ssize_t iov_iter_get_pages(struct iov_iter *i, - struct page **pages, unsigned maxpages, + struct page **pages, size_t maxsize, unsigned maxpages, size_t *start) { if (i->type & ITER_BVEC) - return get_pages_bvec(i, pages, maxpages, start); + return get_pages_bvec(i, pages, maxsize, maxpages, start); else - return get_pages_iovec(i, pages, maxpages, start); + return get_pages_iovec(i, pages, maxsize, maxpages, start); } EXPORT_SYMBOL(iov_iter_get_pages);