From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matthew Wilcox Subject: [PATCH v6 58/99] dax: Convert lock_slot to XArray Date: Wed, 17 Jan 2018 12:21:22 -0800 Message-ID: <20180117202203.19756-59-willy@infradead.org> References: <20180117202203.19756-1-willy@infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from sfi-mx-2.v28.ch3.sourceforge.com ([172.29.28.192] helo=mx.sourceforge.net) by sfs-ml-3.v29.ch3.sourceforge.com with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.89) (envelope-from ) id 1ebuEc-00039c-3c for linux-f2fs-devel@lists.sourceforge.net; Wed, 17 Jan 2018 20:22:58 +0000 Received: from bombadil.infradead.org ([65.50.211.133]) by sfi-mx-2.v28.ch3.sourceforge.com with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.89) id 1ebuEb-000302-6b for linux-f2fs-devel@lists.sourceforge.net; Wed, 17 Jan 2018 20:22:58 +0000 In-Reply-To: <20180117202203.19756-1-willy@infradead.org> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linux-f2fs-devel-bounces@lists.sourceforge.net To: linux-kernel@vger.kernel.org Cc: linux-s390@vger.kernel.org, David Howells , linux-nilfs@vger.kernel.org, Matthew Wilcox , linux-sh@vger.kernel.org, intel-gfx@lists.freedesktop.org, linux-usb@vger.kernel.org, linux-remoteproc@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-xfs@vger.kernel.org, linux-mm@kvack.org, iommu@lists.linux-foundation.org, Stefano Stabellini , linux-fsdevel@vger.kernel.org, cgroups@vger.kernel.org, Bjorn Andersson , linux-btrfs@vger.kernel.org From: Matthew Wilcox Signed-off-by: Matthew Wilcox --- fs/dax.c | 22 ++++++++++++---------- 1 file changed, 12 insertions(+), 10 deletions(-) diff --git a/fs/dax.c b/fs/dax.c index f3463d93a6ce..8eab0b56f7f9 100644 --- a/fs/dax.c +++ b/fs/dax.c @@ -188,12 +188,11 @@ static void dax_wake_mapping_entry_waiter(struct address_space *mapping, /* * Mark the given slot as locked. Must be called with xa_lock held. */ -static inline void *lock_slot(struct address_space *mapping, void **slot) +static inline void *lock_slot(struct xa_state *xas) { - unsigned long v = xa_to_value( - radix_tree_deref_slot_protected(slot, &mapping->pages.xa_lock)); + unsigned long v = xa_to_value(xas_load(xas)); void *entry = xa_mk_value(v | DAX_ENTRY_LOCK); - radix_tree_replace_slot(&mapping->pages, slot, entry); + xas_store(xas, entry); return entry; } @@ -244,7 +243,7 @@ static void dax_unlock_mapping_entry(struct address_space *mapping, xas_lock_irq(&xas); entry = xas_load(&xas); - if (WARN_ON_ONCE(!entry || !xa_is_value(entry) || !dax_locked(entry))) { + if (WARN_ON_ONCE(!xa_is_value(entry) || !dax_locked(entry))) { xas_unlock_irq(&xas); return; } @@ -303,6 +302,7 @@ static void put_unlocked_mapping_entry(struct address_space *mapping, static void *grab_mapping_entry(struct address_space *mapping, pgoff_t index, unsigned long size_flag) { + XA_STATE(xas, &mapping->pages, index); bool pmd_downgrade = false; /* splitting 2MiB entry into 4k entries? */ void *entry, **slot; @@ -341,7 +341,7 @@ static void *grab_mapping_entry(struct address_space *mapping, pgoff_t index, * Make sure 'entry' remains valid while we drop * xa_lock. */ - entry = lock_slot(mapping, slot); + entry = lock_slot(&xas); } xa_unlock_irq(&mapping->pages); @@ -408,7 +408,7 @@ static void *grab_mapping_entry(struct address_space *mapping, pgoff_t index, xa_unlock_irq(&mapping->pages); return entry; } - entry = lock_slot(mapping, slot); + entry = lock_slot(&xas); out_unlock: xa_unlock_irq(&mapping->pages); return entry; @@ -639,6 +639,7 @@ static int dax_writeback_one(struct block_device *bdev, pgoff_t index, void *entry) { struct radix_tree_root *pages = &mapping->pages; + XA_STATE(xas, pages, index); void *entry2, **slot, *kaddr; long ret = 0, id; sector_t sector; @@ -675,7 +676,7 @@ static int dax_writeback_one(struct block_device *bdev, if (!radix_tree_tag_get(pages, index, PAGECACHE_TAG_TOWRITE)) goto put_unlocked; /* Lock the entry to serialize with page faults */ - entry = lock_slot(mapping, slot); + entry = lock_slot(&xas); /* * We can clear the tag now but we have to be careful so that concurrent * dax_writeback_one() calls for the same index cannot finish before we @@ -1500,8 +1501,9 @@ static int dax_insert_pfn_mkwrite(struct vm_fault *vmf, pfn_t pfn) { struct address_space *mapping = vmf->vma->vm_file->f_mapping; - void *entry, **slot; pgoff_t index = vmf->pgoff; + XA_STATE(xas, &mapping->pages, index); + void *entry, **slot; int vmf_ret, error; xa_lock_irq(&mapping->pages); @@ -1517,7 +1519,7 @@ static int dax_insert_pfn_mkwrite(struct vm_fault *vmf, return VM_FAULT_NOPAGE; } radix_tree_tag_set(&mapping->pages, index, PAGECACHE_TAG_DIRTY); - entry = lock_slot(mapping, slot); + entry = lock_slot(&xas); xa_unlock_irq(&mapping->pages); switch (pe_size) { case PE_SIZE_PTE: -- 2.15.1 ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot