[to-be-updated] mm-vmalloc-map-contiguous-pages-in-batches-for-vmap-if-possible-fix.patch removed from -mm tree

[Andrew Morton <akpm@linux-foundation.org>]

The quilt patch titled
     Subject: mm/vmalloc: simplify vmap batching helper and limit scan by PFN alignment
has been removed from the -mm tree.  Its filename was
     mm-vmalloc-map-contiguous-pages-in-batches-for-vmap-if-possible-fix.patch

This patch was dropped because an updated version will be issued

------------------------------------------------------
From: Wen Jiang <jiangwenxiaomi@gmail.com>
Subject: mm/vmalloc: simplify vmap batching helper and limit scan by PFN alignment
Date: Wed, 22 Jul 2026 16:58:41 +0800

Pass the current page pointer directly to the batching helper, and limit
the contiguous scan by PFN alignment before checking for a batch size. 
This keeps the helper interface simpler and avoids scanning more pages
than can actually be mapped together.

Link: https://lore.kernel.org/20260722085841.3047673-1-jiangwen6@xiaomi.com
Signed-off-by: Wen Jiang <jiangwen6@xiaomi.com>
Suggested-by: David Hildenbrand (Arm) <david@kernel.org>
Cc: Andrew Donnellan <ajd@linux.ibm.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: "Barry Song (Xiaomi)" <baohua@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Leo Yan <leo.yan@arm.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: "Uladzislau Rezki (Sony)" <urezki@gmail.com>
Cc: Will Deacon <will@kernel.org>
Cc: Xueyuan Chen <xueyuan.chen21@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/vmalloc.c |   34 +++++++++++++++++-----------------
 1 file changed, 17 insertions(+), 17 deletions(-)

--- a/mm/vmalloc.c~mm-vmalloc-map-contiguous-pages-in-batches-for-vmap-if-possible-fix
+++ a/mm/vmalloc.c
@@ -3585,7 +3585,7 @@ static inline unsigned int vm_shift(pgpr
 }
 
 static inline int get_vmap_batch_order(struct page **pages,
-		pgprot_t prot, unsigned int max_steps, unsigned int idx)
+		pgprot_t prot, unsigned int nr_pages)
 {
 	unsigned long pfn;
 	unsigned int nr_contig;
@@ -3594,16 +3594,16 @@ static inline int get_vmap_batch_order(s
 	if (!IS_ENABLED(CONFIG_HAVE_ARCH_HUGE_VMAP))
 		return 0;
 
-	nr_contig = num_pages_contiguous(&pages[idx], max_steps);
+	/* Limit nr_pages by pfn alignment */
+	pfn = page_to_pfn(*pages);
+	if (pfn > 0)
+		nr_pages = min_t(unsigned int, nr_pages, 1UL << __ffs(pfn));
+
+	nr_contig = num_pages_contiguous(pages, nr_pages);
 	if (nr_contig < 2)
 		return 0;
 
 	order = ilog2(nr_contig);
-	pfn = page_to_pfn(pages[idx]);
-
-	/* Limit order by pfn alignment */
-	if (pfn > 0)
-		order = min_t(int, order, __ffs(pfn));
 
 	if (vm_shift(prot, PAGE_SIZE << order) == PAGE_SHIFT)
 		return 0;
@@ -3614,8 +3614,8 @@ static inline int get_vmap_batch_order(s
 static int vmap_pages_range_batched(unsigned long addr, unsigned long end,
 		pgprot_t prot, struct page **pages)
 {
-	unsigned int count = (end - addr) >> PAGE_SHIFT;
-	unsigned int prev_shift = 0, idx = 0;
+	const unsigned int nr_pages = (end - addr) >> PAGE_SHIFT;
+	unsigned int prev_shift = 0, batch_start = 0;
 	unsigned long map_addr = addr, batch_end = addr;
 	int err;
 
@@ -3624,26 +3624,26 @@ static int vmap_pages_range_batched(unsi
 	if (err)
 		goto out;
 
-	for (unsigned int i = 0; i < count; ) {
+	for (unsigned int i = 0; i < nr_pages; ) {
 		unsigned int shift = PAGE_SHIFT +
-			get_vmap_batch_order(pages, prot, count - i, i);
+			get_vmap_batch_order(pages + i, prot, nr_pages - i);
 
 		if (!i)
 			prev_shift = shift;
 
 		if (shift != prev_shift) {
 			err = vmap_pages_range_noflush_walk(map_addr, batch_end,
-					prot, pages + idx, prev_shift);
+					prot, pages + batch_start, prev_shift);
 			if (err)
 				goto out;
 			prev_shift = shift;
 			map_addr = batch_end;
-			idx = i;
+			batch_start = i;
 		}
 
 		/*
-		 * Once small pages are encountered, the remaining pages
-		 * are likely small as well.
+		 * Once we fail to batch pages, we expect to fail batching
+		 * for all remaining pages, so just give up.
 		 */
 		if (shift == PAGE_SHIFT)
 			break;
@@ -3654,8 +3654,8 @@ static int vmap_pages_range_batched(unsi
 
 	/* Remaining */
 	if (map_addr < end)
-		err = vmap_pages_range_noflush_walk(map_addr, end,
-				prot, pages + idx, prev_shift);
+		err = vmap_pages_range_noflush_walk(map_addr, end, prot,
+				pages + batch_start, prev_shift);
 
 out:
 	flush_cache_vmap(addr, end);
_

Patches currently in -mm which might be from jiangwenxiaomi@gmail.com are