From b90ca5cc32f59bb214847c6855959702f00c6801 Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Tue, 11 Sep 2018 21:27:44 -0700 Subject: filesystem-dax: Fix use of zero page Use my_zero_pfn instead of ZERO_PAGE(), and pass the vaddr to it instead of zero so it works on MIPS and s390 who reference the vaddr to select a zero page. Cc: Fixes: 91d25ba8a6b0 ("dax: use common 4k zero page for dax mmap reads") Signed-off-by: Matthew Wilcox Reviewed-by: Ross Zwisler Signed-off-by: Dan Williams --- fs/dax.c | 13 ++----------- 1 file changed, 2 insertions(+), 11 deletions(-) (limited to 'fs/dax.c') diff --git a/fs/dax.c b/fs/dax.c index f32d7125ad0f..b68ce484e1be 100644 --- a/fs/dax.c +++ b/fs/dax.c @@ -1120,21 +1120,12 @@ static vm_fault_t dax_load_hole(struct address_space *mapping, void *entry, { struct inode *inode = mapping->host; unsigned long vaddr = vmf->address; - vm_fault_t ret = VM_FAULT_NOPAGE; - struct page *zero_page; - pfn_t pfn; - - zero_page = ZERO_PAGE(0); - if (unlikely(!zero_page)) { - ret = VM_FAULT_OOM; - goto out; - } + pfn_t pfn = pfn_to_pfn_t(my_zero_pfn(vaddr)); + vm_fault_t ret; - pfn = page_to_pfn_t(zero_page); dax_insert_mapping_entry(mapping, vmf, entry, pfn, RADIX_DAX_ZERO_PAGE, false); ret = vmf_insert_mixed(vmf->vma, vaddr, pfn); -out: trace_dax_load_hole(inode, vmf, ret); return ret; } -- cgit v1.2.3 From f52afc93cd018fe6910133a05d44671192d1aeb0 Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Thu, 27 Sep 2018 13:23:32 +0200 Subject: dax: Fix deadlock in dax_lock_mapping_entry() When dax_lock_mapping_entry() has to sleep to obtain entry lock, it will fail to unlock mapping->i_pages spinlock and thus immediately deadlock against itself when retrying to grab the entry lock again. Fix the problem by unlocking mapping->i_pages before retrying. Fixes: c2a7d2a11552 ("filesystem-dax: Introduce dax_lock_mapping_entry()") Reported-by: Barret Rhoden Signed-off-by: Jan Kara Signed-off-by: Dan Williams --- fs/dax.c | 1 + 1 file changed, 1 insertion(+) (limited to 'fs/dax.c') diff --git a/fs/dax.c b/fs/dax.c index f32d7125ad0f..e4ef8af31aa6 100644 --- a/fs/dax.c +++ b/fs/dax.c @@ -447,6 +447,7 @@ bool dax_lock_mapping_entry(struct page *page) xa_unlock_irq(&mapping->i_pages); break; } else if (IS_ERR(entry)) { + xa_unlock_irq(&mapping->i_pages); WARN_ON_ONCE(PTR_ERR(entry) != -EAGAIN); continue; } -- cgit v1.2.3