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authorBreno Leitao <leitao@debian.org>2026-08-05 07:52:36 -0700
committerTejun Heo <tj@kernel.org>2026-08-10 11:47:20 -1000
commita5bde5d8fde8a8cb28e59a672d5ddc5b9c1e7656 (patch)
tree39f5b258386e1127d253d293194e9a2991bf3c34 /drivers/mtd/mtdblock_ro.c
downloadlinux-stable-a5bde5d8fde8a8cb28e59a672d5ddc5b9c1e7656.tar.gz
linux-stable-a5bde5d8fde8a8cb28e59a672d5ddc5b9c1e7656.zip
workqueue: skip the node_nr_active update for non-unbound workqueuesgrafted
apply_wqattrs_commit() updates node_nr_active->max unconditionally. wq->node_nr_active[] is only allocated for unbound workqueues, so guard the call before per-cpu workqueues start using this path. No functional change: only unbound workqueues reach apply_wqattrs_*() today. Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Tejun Heo <tj@kernel.org>
Diffstat (limited to 'drivers/mtd/mtdblock_ro.c')
-rw-r--r--drivers/mtd/mtdblock_ro.c80
1 files changed, 80 insertions, 0 deletions
diff --git a/drivers/mtd/mtdblock_ro.c b/drivers/mtd/mtdblock_ro.c
new file mode 100644
index 000000000..e564521d6
--- /dev/null
+++ b/drivers/mtd/mtdblock_ro.c
@@ -0,0 +1,80 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Simple read-only (writable only for RAM) mtdblock driver
+ *
+ * Copyright © 2001-2010 David Woodhouse <dwmw2@infradead.org>
+ */
+
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/blktrans.h>
+#include <linux/module.h>
+#include <linux/major.h>
+
+static int mtdblock_readsect(struct mtd_blktrans_dev *dev,
+ unsigned long block, char *buf)
+{
+ size_t retlen;
+ int err;
+
+ err = mtd_read(dev->mtd, (block * 512), 512, &retlen, buf);
+ if (err && !mtd_is_bitflip(err))
+ return 1;
+ return 0;
+}
+
+static int mtdblock_writesect(struct mtd_blktrans_dev *dev,
+ unsigned long block, char *buf)
+{
+ size_t retlen;
+
+ if (mtd_write(dev->mtd, (block * 512), 512, &retlen, buf))
+ return 1;
+ return 0;
+}
+
+static void mtdblock_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd)
+{
+ struct mtd_blktrans_dev *dev = kzalloc_obj(*dev);
+
+ if (!dev)
+ return;
+
+ dev->mtd = mtd;
+ dev->devnum = mtd->index;
+
+ dev->size = mtd->size >> 9;
+ dev->tr = tr;
+ dev->readonly = 1;
+
+ if (mtd_type_is_nand(mtd))
+ pr_warn_ratelimited("%s: MTD device '%s' is NAND, please consider using UBI block devices instead.\n",
+ tr->name, mtd->name);
+
+ if (add_mtd_blktrans_dev(dev))
+ kfree(dev);
+}
+
+static void mtdblock_remove_dev(struct mtd_blktrans_dev *dev)
+{
+ del_mtd_blktrans_dev(dev);
+}
+
+static struct mtd_blktrans_ops mtdblock_tr = {
+ .name = "mtdblock",
+ .major = MTD_BLOCK_MAJOR,
+ .part_bits = 0,
+ .blksize = 512,
+ .readsect = mtdblock_readsect,
+ .writesect = mtdblock_writesect,
+ .add_mtd = mtdblock_add_mtd,
+ .remove_dev = mtdblock_remove_dev,
+ .owner = THIS_MODULE,
+};
+
+module_mtd_blktrans(mtdblock_tr);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
+MODULE_DESCRIPTION("Simple read-only block device emulation access to MTD devices");