+ zsmalloc-remove-old-object-read-api.patch added to mm-new branch

+ zsmalloc-remove-old-object-read-api.patch added to mm-new branch

[Andrew Morton]

The patch titled
     Subject: zsmalloc: remove old object read API
has been added to the -mm mm-new branch.  Its filename is
     zsmalloc-remove-old-object-read-api.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/zsmalloc-remove-old-object-read-api.patch

This patch will later appear in the mm-new branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Note, mm-new is a provisional staging ground for work-in-progress
patches, and acceptance into mm-new is a notification for others take
notice and to finish up reviews.  Please do not hesitate to respond to
review feedback and post updated versions to replace or incrementally
fixup patches in mm-new.

The mm-new branch of mm.git is not included in linux-next

If a few days of testing in mm-new is successful, the patch will me moved
into mm.git's mm-unstable branch, which is included in linux-next

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------------------------------------------------------
From: Sergey Senozhatsky <senozhatsky@chromium.org>
Subject: zsmalloc: remove old object read API
Date: Mon, 7 Sep 2026 19:57:29 +0900

There are no users left of the old API, all have switched to SG-list
object read API.  Remove it.

Link: https://lore.kernel.org/20260907105739.1793316-3-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nhat Pham <nphamcs@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/linux/zsmalloc.h |    4 -
 mm/zsmalloc.c            |   77 -------------------------------------
 2 files changed, 81 deletions(-)

--- a/include/linux/zsmalloc.h~zsmalloc-remove-old-object-read-api
+++ a/include/linux/zsmalloc.h
@@ -40,10 +40,6 @@ unsigned int zs_lookup_class_index(struc
 
 void zs_pool_stats(struct zs_pool *pool, struct zs_pool_stats *stats);
 
-void *zs_obj_read_begin(struct zs_pool *pool, unsigned long handle,
-			size_t mem_len, void *local_copy);
-void zs_obj_read_end(struct zs_pool *pool, unsigned long handle,
-		     size_t mem_len, void *handle_mem);
 void zs_obj_read_sg_begin(struct zs_pool *pool, unsigned long handle,
 			  struct scatterlist *sg, size_t mem_len);
 void zs_obj_read_sg_end(struct zs_pool *pool, unsigned long handle);
--- a/mm/zsmalloc.c~zsmalloc-remove-old-object-read-api
+++ a/mm/zsmalloc.c
@@ -1134,83 +1134,6 @@ unsigned long zs_get_total_pages(struct
 }
 EXPORT_SYMBOL_GPL(zs_get_total_pages);
 
-void *zs_obj_read_begin(struct zs_pool *pool, unsigned long handle,
-			size_t mem_len, void *local_copy)
-{
-	struct zspage *zspage;
-	struct zpdesc *zpdesc;
-	unsigned long obj, off;
-	unsigned int obj_idx;
-	struct size_class *class;
-	void *addr;
-
-	/* Guarantee we can get zspage from handle safely */
-	read_lock(&pool->lock);
-	obj = handle_to_obj(handle);
-	obj_to_location(obj, &zpdesc, &obj_idx);
-	zspage = get_zspage(zpdesc);
-
-	/* Make sure migration doesn't move any pages in this zspage */
-	zspage_read_lock(zspage);
-	read_unlock(&pool->lock);
-
-	class = zspage_class(pool, zspage);
-	off = offset_in_page(class->size * obj_idx);
-
-	if (!ZsHugePage(zspage))
-		off += ZS_HANDLE_SIZE;
-
-	if (off + mem_len <= PAGE_SIZE) {
-		/* this object is contained entirely within a page */
-		addr = kmap_local_zpdesc(zpdesc);
-		addr += off;
-	} else {
-		size_t sizes[2];
-
-		/* this object spans two pages */
-		sizes[0] = PAGE_SIZE - off;
-		sizes[1] = mem_len - sizes[0];
-		addr = local_copy;
-
-		memcpy_from_page(addr, zpdesc_page(zpdesc),
-				 off, sizes[0]);
-		zpdesc = get_next_zpdesc(zpdesc);
-		memcpy_from_page(addr + sizes[0],
-				 zpdesc_page(zpdesc),
-				 0, sizes[1]);
-	}
-
-	return addr;
-}
-EXPORT_SYMBOL_GPL(zs_obj_read_begin);
-
-void zs_obj_read_end(struct zs_pool *pool, unsigned long handle,
-		     size_t mem_len, void *handle_mem)
-{
-	struct zspage *zspage;
-	struct zpdesc *zpdesc;
-	unsigned long obj, off;
-	unsigned int obj_idx;
-	struct size_class *class;
-
-	obj = handle_to_obj(handle);
-	obj_to_location(obj, &zpdesc, &obj_idx);
-	zspage = get_zspage(zpdesc);
-	class = zspage_class(pool, zspage);
-	off = offset_in_page(class->size * obj_idx);
-
-	if (!ZsHugePage(zspage))
-		off += ZS_HANDLE_SIZE;
-
-	if (off + mem_len <= PAGE_SIZE) {
-		handle_mem -= off;
-		kunmap_local(handle_mem);
-	}
-
-	zspage_read_unlock(zspage);
-}
-EXPORT_SYMBOL_GPL(zs_obj_read_end);
-
 void zs_obj_read_sg_begin(struct zs_pool *pool, unsigned long handle,
 			  struct scatterlist *sg, size_t mem_len)
 {
_

Patches currently in -mm which might be from senozhatsky@chromium.org are

zram-remove-unreachable-kernel_read_file_from_path-return-check.patch
zram-convert-to-sg-list-zsmalloc-object-read-api.patch
zsmalloc-remove-old-object-read-api.patch