Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754275AbdGXLfz (ORCPT ); Mon, 24 Jul 2017 07:35:55 -0400 Received: from mx2.suse.de ([195.135.220.15]:51567 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752772AbdGXLft (ORCPT ); Mon, 24 Jul 2017 07:35:49 -0400 Date: Mon, 24 Jul 2017 13:35:42 +0200 From: Jan Kara To: Ross Zwisler Cc: Andrew Morton , linux-kernel@vger.kernel.org, "Darrick J. Wong" , "Theodore Ts'o" , Alexander Viro , Andreas Dilger , Christoph Hellwig , Dan Williams , Dave Chinner , David Airlie , Ingo Molnar , Inki Dae , Jan Kara , Jonathan Corbet , Joonyoung Shim , Krzysztof Kozlowski , Kukjin Kim , Kyungmin Park , Matthew Wilcox , Patrik Jakobsson , Rob Clark , Seung-Woo Kim , Steven Rostedt , Tomi Valkeinen , dri-devel@lists.freedesktop.org, freedreno@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org, linux-arm-msm@vger.kernel.org, linux-doc@vger.kernel.org, linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-nvdimm@lists.01.org, linux-samsung-soc@vger.kernel.org, linux-xfs@vger.kernel.org Subject: Re: [PATCH v4 2/5] dax: relocate some dax functions Message-ID: <20170724113542.GJ652@quack2.suse.cz> References: <20170721223956.29485-1-ross.zwisler@linux.intel.com> <20170721223956.29485-3-ross.zwisler@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170721223956.29485-3-ross.zwisler@linux.intel.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6435 Lines: 196 On Fri 21-07-17 16:39:52, Ross Zwisler wrote: > dax_load_hole() will soon need to call dax_insert_mapping_entry(), so it > needs to be moved lower in dax.c so the definition exists. > > dax_wake_mapping_entry_waiter() will soon be removed from dax.h and be made > static to dax.c, so we need to move its definition above all its callers. > > Signed-off-by: Ross Zwisler Looks good. You can add: Reviewed-by: Jan Kara Honza > --- > fs/dax.c | 138 +++++++++++++++++++++++++++++++-------------------------------- > 1 file changed, 69 insertions(+), 69 deletions(-) > > diff --git a/fs/dax.c b/fs/dax.c > index c844a51..779dc5e 100644 > --- a/fs/dax.c > +++ b/fs/dax.c > @@ -121,6 +121,31 @@ static int wake_exceptional_entry_func(wait_queue_entry_t *wait, unsigned int mo > } > > /* > + * We do not necessarily hold the mapping->tree_lock when we call this > + * function so it is possible that 'entry' is no longer a valid item in the > + * radix tree. This is okay because all we really need to do is to find the > + * correct waitqueue where tasks might be waiting for that old 'entry' and > + * wake them. > + */ > +void dax_wake_mapping_entry_waiter(struct address_space *mapping, > + pgoff_t index, void *entry, bool wake_all) > +{ > + struct exceptional_entry_key key; > + wait_queue_head_t *wq; > + > + wq = dax_entry_waitqueue(mapping, index, entry, &key); > + > + /* > + * Checking for locked entry and prepare_to_wait_exclusive() happens > + * under mapping->tree_lock, ditto for entry handling in our callers. > + * So at this point all tasks that could have seen our entry locked > + * must be in the waitqueue and the following check will see them. > + */ > + if (waitqueue_active(wq)) > + __wake_up(wq, TASK_NORMAL, wake_all ? 0 : 1, &key); > +} > + > +/* > * Check whether the given slot is locked. The function must be called with > * mapping->tree_lock held > */ > @@ -392,31 +417,6 @@ static void *grab_mapping_entry(struct address_space *mapping, pgoff_t index, > return entry; > } > > -/* > - * We do not necessarily hold the mapping->tree_lock when we call this > - * function so it is possible that 'entry' is no longer a valid item in the > - * radix tree. This is okay because all we really need to do is to find the > - * correct waitqueue where tasks might be waiting for that old 'entry' and > - * wake them. > - */ > -void dax_wake_mapping_entry_waiter(struct address_space *mapping, > - pgoff_t index, void *entry, bool wake_all) > -{ > - struct exceptional_entry_key key; > - wait_queue_head_t *wq; > - > - wq = dax_entry_waitqueue(mapping, index, entry, &key); > - > - /* > - * Checking for locked entry and prepare_to_wait_exclusive() happens > - * under mapping->tree_lock, ditto for entry handling in our callers. > - * So at this point all tasks that could have seen our entry locked > - * must be in the waitqueue and the following check will see them. > - */ > - if (waitqueue_active(wq)) > - __wake_up(wq, TASK_NORMAL, wake_all ? 0 : 1, &key); > -} > - > static int __dax_invalidate_mapping_entry(struct address_space *mapping, > pgoff_t index, bool trunc) > { > @@ -468,50 +468,6 @@ int dax_invalidate_mapping_entry_sync(struct address_space *mapping, > return __dax_invalidate_mapping_entry(mapping, index, false); > } > > -/* > - * The user has performed a load from a hole in the file. Allocating > - * a new page in the file would cause excessive storage usage for > - * workloads with sparse files. We allocate a page cache page instead. > - * We'll kick it out of the page cache if it's ever written to, > - * otherwise it will simply fall out of the page cache under memory > - * pressure without ever having been dirtied. > - */ > -static int dax_load_hole(struct address_space *mapping, void **entry, > - struct vm_fault *vmf) > -{ > - struct inode *inode = mapping->host; > - struct page *page; > - int ret; > - > - /* Hole page already exists? Return it... */ > - if (!radix_tree_exceptional_entry(*entry)) { > - page = *entry; > - goto finish_fault; > - } > - > - /* This will replace locked radix tree entry with a hole page */ > - page = find_or_create_page(mapping, vmf->pgoff, > - vmf->gfp_mask | __GFP_ZERO); > - if (!page) { > - ret = VM_FAULT_OOM; > - goto out; > - } > - > -finish_fault: > - vmf->page = page; > - ret = finish_fault(vmf); > - vmf->page = NULL; > - *entry = page; > - if (!ret) { > - /* Grab reference for PTE that is now referencing the page */ > - get_page(page); > - ret = VM_FAULT_NOPAGE; > - } > -out: > - trace_dax_load_hole(inode, vmf, ret); > - return ret; > -} > - > static int copy_user_dax(struct block_device *bdev, struct dax_device *dax_dev, > sector_t sector, size_t size, struct page *to, > unsigned long vaddr) > @@ -938,6 +894,50 @@ int dax_pfn_mkwrite(struct vm_fault *vmf) > } > EXPORT_SYMBOL_GPL(dax_pfn_mkwrite); > > +/* > + * The user has performed a load from a hole in the file. Allocating > + * a new page in the file would cause excessive storage usage for > + * workloads with sparse files. We allocate a page cache page instead. > + * We'll kick it out of the page cache if it's ever written to, > + * otherwise it will simply fall out of the page cache under memory > + * pressure without ever having been dirtied. > + */ > +static int dax_load_hole(struct address_space *mapping, void **entry, > + struct vm_fault *vmf) > +{ > + struct inode *inode = mapping->host; > + struct page *page; > + int ret; > + > + /* Hole page already exists? Return it... */ > + if (!radix_tree_exceptional_entry(*entry)) { > + page = *entry; > + goto finish_fault; > + } > + > + /* This will replace locked radix tree entry with a hole page */ > + page = find_or_create_page(mapping, vmf->pgoff, > + vmf->gfp_mask | __GFP_ZERO); > + if (!page) { > + ret = VM_FAULT_OOM; > + goto out; > + } > + > +finish_fault: > + vmf->page = page; > + ret = finish_fault(vmf); > + vmf->page = NULL; > + *entry = page; > + if (!ret) { > + /* Grab reference for PTE that is now referencing the page */ > + get_page(page); > + ret = VM_FAULT_NOPAGE; > + } > +out: > + trace_dax_load_hole(inode, vmf, ret); > + return ret; > +} > + > static bool dax_range_is_aligned(struct block_device *bdev, > unsigned int offset, unsigned int length) > { > -- > 2.9.4 > -- Jan Kara SUSE Labs, CR