From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lorenzo Stoakes Subject: [PATCH 04/10] mm: replace get_user_pages_locked() write/force parameters with gup_flags Date: Thu, 13 Oct 2016 01:20:14 +0100 Message-ID: <20161013002020.3062-5-lstoakes@gmail.com> References: <20161013002020.3062-1-lstoakes@gmail.com> Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=J7hNHJkTC7Ffiu2FXRztTaYWMFhFliujw26loP3uwnI=; b=Tf0wJXb+x8V7G23m+hVL27B49GOArO+pmF6+5AydlzCoHUiS5BCwtczvtJITmHyONk xlqI68CjkZmB0jAUH1zeQI9CKhnAgLk/qblxYjUoAUKJn99bM6Xm+n2mB9J4D2UD3sax GcCofaZivJ+luOuMXPpHujk/Y5Pxwry/DzEf8+PCb1W0kxiYDVuWpqSBJkHEZQIYO9Da LaET67yt7dEnS/e5ASHOwKJdZtteRBfbqVjw4/7BWUEz1lCaVW759sNBGYmR7lr/+9dR ZhN3Sh+rPEXzf3qXPUwCNhEFMhIE+JSx5uAKWQIIrs+7U30zHYyYVdVAx3lk+iyzalDh Bz1A== In-Reply-To: <20161013002020.3062-1-lstoakes@gmail.com> Sender: owner-linux-mm@kvack.org List-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-mm@kvack.org Cc: Linus Torvalds , Jan Kara , Hugh Dickins , Dave Hansen , Rik van Riel , Mel Gorman , Andrew Morton , adi-buildroot-devel@lists.sourceforge.net, ceph-devel@vger.kernel.org, dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, kvm@vger.kernel.org, linux-alpha@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-cris-kernel@axis.com, linux-fbdev@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-ia64@vger.kernel.org, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, linux-mips@linux-mips.org, linux-rdma@vger.kernel.org, linux-s390@vger.kernel.org, linux-samsung-soc@vger.kernel.org, linux-scsi@vger.kernel.org, linux-security-module@vger.kernel.org, linux-sh@vger.kerne This patch removes the write and force parameters from get_user_pages_locked() and replaces them with a gup_flags parameter to make the use of FOLL_FORCE explicit in callers as use of this flag can result in surprising behaviour (and hence bugs) within the mm subsystem. Signed-off-by: Lorenzo Stoakes --- include/linux/mm.h | 2 +- mm/frame_vector.c | 8 +++++++- mm/gup.c | 12 +++--------- mm/nommu.c | 5 ++++- 4 files changed, 15 insertions(+), 12 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index 6adc4bc..27ab538 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1282,7 +1282,7 @@ long get_user_pages(unsigned long start, unsigned long nr_pages, int write, int force, struct page **pages, struct vm_area_struct **vmas); long get_user_pages_locked(unsigned long start, unsigned long nr_pages, - int write, int force, struct page **pages, int *locked); + unsigned int gup_flags, struct page **pages, int *locked); long __get_user_pages_unlocked(struct task_struct *tsk, struct mm_struct *mm, unsigned long start, unsigned long nr_pages, struct page **pages, unsigned int gup_flags); diff --git a/mm/frame_vector.c b/mm/frame_vector.c index 381bb07..81b6749 100644 --- a/mm/frame_vector.c +++ b/mm/frame_vector.c @@ -41,10 +41,16 @@ int get_vaddr_frames(unsigned long start, unsigned int nr_frames, int ret = 0; int err; int locked; + unsigned int gup_flags = 0; if (nr_frames == 0) return 0; + if (write) + gup_flags |= FOLL_WRITE; + if (force) + gup_flags |= FOLL_FORCE; + if (WARN_ON_ONCE(nr_frames > vec->nr_allocated)) nr_frames = vec->nr_allocated; @@ -59,7 +65,7 @@ int get_vaddr_frames(unsigned long start, unsigned int nr_frames, vec->got_ref = true; vec->is_pfns = false; ret = get_user_pages_locked(start, nr_frames, - write, force, (struct page **)(vec->ptrs), &locked); + gup_flags, (struct page **)(vec->ptrs), &locked); goto out; } diff --git a/mm/gup.c b/mm/gup.c index cfcb014..7a0d033 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -838,18 +838,12 @@ static __always_inline long __get_user_pages_locked(struct task_struct *tsk, * up_read(&mm->mmap_sem); */ long get_user_pages_locked(unsigned long start, unsigned long nr_pages, - int write, int force, struct page **pages, + unsigned int gup_flags, struct page **pages, int *locked) { - unsigned int flags = FOLL_TOUCH; - - if (write) - flags |= FOLL_WRITE; - if (force) - flags |= FOLL_FORCE; - return __get_user_pages_locked(current, current->mm, start, nr_pages, - pages, NULL, locked, true, flags); + pages, NULL, locked, true, + gup_flags | FOLL_TOUCH); } EXPORT_SYMBOL(get_user_pages_locked); diff --git a/mm/nommu.c b/mm/nommu.c index 7e27add..842cfdd 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -176,9 +176,12 @@ long get_user_pages(unsigned long start, unsigned long nr_pages, EXPORT_SYMBOL(get_user_pages); long get_user_pages_locked(unsigned long start, unsigned long nr_pages, - int write, int force, struct page **pages, + unsigned int gup_flags, struct page **pages, int *locked) { + int write = gup_flags & FOLL_WRITE; + int force = gup_flags & FOLL_FORCE; + return get_user_pages(start, nr_pages, write, force, pages, NULL); } EXPORT_SYMBOL(get_user_pages_locked); -- 2.10.0 -- 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