Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block into for-3.18

This is to receive 0a30288da1ae ("blk-mq, percpu_ref: implement a
kludge for SCSI blk-mq stall during probe") which implements
__percpu_ref_kill_expedited() to work around SCSI blk-mq stall.  The
commit reverted and patches to implement proper fix will be added.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Kent Overstreet <kmo@daterainc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Christoph Hellwig <hch@lst.de>

1 files changed, 22 insertions, 16 deletions

diff --git a/arch/xtensa/mm/mmu.c b/arch/xtensa/mm/mmu.c
index 3429b483d9f..abe4513eb0d 100644
--- a/arch/xtensa/mm/mmu.c
+++ b/arch/xtensa/mm/mmu.c
@@ -18,32 +18,38 @@
 #include <asm/io.h>
 
 #if defined(CONFIG_HIGHMEM)
-static void * __init init_pmd(unsigned long vaddr)
+static void * __init init_pmd(unsigned long vaddr, unsigned long n_pages)
 {
 	pgd_t *pgd = pgd_offset_k(vaddr);
 	pmd_t *pmd = pmd_offset(pgd, vaddr);
+	pte_t *pte;
+	unsigned long i;
 
-	if (pmd_none(*pmd)) {
-		unsigned i;
-		pte_t *pte = alloc_bootmem_low_pages(PAGE_SIZE);
+	n_pages = ALIGN(n_pages, PTRS_PER_PTE);
 
-		for (i = 0; i < 1024; i++)
-			pte_clear(NULL, 0, pte + i);
+	pr_debug("%s: vaddr: 0x%08lx, n_pages: %ld\n",
+		 __func__, vaddr, n_pages);
 
-		set_pmd(pmd, __pmd(((unsigned long)pte) & PAGE_MASK));
-		BUG_ON(pte != pte_offset_kernel(pmd, 0));
-		pr_debug("%s: vaddr: 0x%08lx, pmd: 0x%p, pte: 0x%p\n",
-			 __func__, vaddr, pmd, pte);
-		return pte;
-	} else {
-		return pte_offset_kernel(pmd, 0);
+	pte = alloc_bootmem_low_pages(n_pages * sizeof(pte_t));
+
+	for (i = 0; i < n_pages; ++i)
+		pte_clear(NULL, 0, pte + i);
+
+	for (i = 0; i < n_pages; i += PTRS_PER_PTE, ++pmd) {
+		pte_t *cur_pte = pte + i;
+
+		BUG_ON(!pmd_none(*pmd));
+		set_pmd(pmd, __pmd(((unsigned long)cur_pte) & PAGE_MASK));
+		BUG_ON(cur_pte != pte_offset_kernel(pmd, 0));
+		pr_debug("%s: pmd: 0x%p, pte: 0x%p\n",
+			 __func__, pmd, cur_pte);
 	}
+	return pte;
 }
 
 static void __init fixedrange_init(void)
 {
-	BUILD_BUG_ON(FIXADDR_SIZE > PMD_SIZE);
-	init_pmd(__fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK);
+	init_pmd(__fix_to_virt(0), __end_of_fixed_addresses);
 }
 #endif
 
@@ -52,7 +58,7 @@ void __init paging_init(void)
 	memset(swapper_pg_dir, 0, PAGE_SIZE);
 #ifdef CONFIG_HIGHMEM
 	fixedrange_init();
-	pkmap_page_table = init_pmd(PKMAP_BASE);
+	pkmap_page_table = init_pmd(PKMAP_BASE, LAST_PKMAP);
 	kmap_init();
 #endif
 }