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authorLinus Torvalds <torvalds@linux-foundation.org>2026-10-02 12:17:24 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-10-02 12:17:24 -0700
commit3f1fe48a36b0b6722dc3fd421d93512bac138e9a (patch)
treeb767d7f6e26bc64334d3f14f8422d187239dc45d /drivers/mtd/nand/bbt.c
downloadlinux-stable-3f1fe48a36b0b6722dc3fd421d93512bac138e9a.tar.gz
linux-stable-3f1fe48a36b0b6722dc3fd421d93512bac138e9a.zip
Merge tag 'io_uring-7.3-20261002' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linuxgrafted
Pull io_uring fixes from Jens Axboe: - Fix a task_work add use-after-free with SQPOLL. The sqpoll thread could pop and complete the last request while io_req_normal_work_add() was still looking at them after the mpscq push. Use the same approach as DEFER_TASKRUN to protect from that, holding an RCU read lock across the add, and have exit wait for an RCU grace period for SQPOLL rings as well. - CQE32 ring fixes: correct the free entry check for 32b CQEs, zero the big_cqe for aux CQEs, and only post the dummy skip CQE on CQE_MIXED rings - Mark the source filter table as COW when cloning bpf filters, so registering another filter on the source doesn't modify the shared table in place - Initialize the task context before running the BPF loop - Requeue zcrx multishot receives stopped by a local resource - End a TX_TIMESTAMP multishot cmd when the CQ is full (lollipopkit) * tag 'io_uring-7.3-20261002' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: io_uring: fix task_work add use-after-free with SQPOLL io_uring/cmd_net: end TX_TIMESTAMP multishot when the CQ is full io_uring/zcrx: requeue multishot receives stopped by a local resource io_uring: initialize task context before running the BPF loop io_uring: zero big_cqe for aux CQEs on CQE32 rings io_uring: fix free entry check for 32b CQEs on CQE32 rings io_uring: only post the dummy skip CQE on CQE_MIXED rings io_uring/bpf_filter: mark source as COW when cloning filters
Diffstat (limited to 'drivers/mtd/nand/bbt.c')
-rw-r--r--drivers/mtd/nand/bbt.c128
1 files changed, 128 insertions, 0 deletions
diff --git a/drivers/mtd/nand/bbt.c b/drivers/mtd/nand/bbt.c
new file mode 100644
index 000000000..db4f93a90
--- /dev/null
+++ b/drivers/mtd/nand/bbt.c
@@ -0,0 +1,128 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2017 Free Electrons
+ *
+ * Authors:
+ * Boris Brezillon <boris.brezillon@free-electrons.com>
+ * Peter Pan <peterpandong@micron.com>
+ */
+
+#define pr_fmt(fmt) "nand-bbt: " fmt
+
+#include <linux/mtd/nand.h>
+#include <linux/slab.h>
+
+/**
+ * nanddev_bbt_init() - Initialize the BBT (Bad Block Table)
+ * @nand: NAND device
+ *
+ * Initialize the in-memory BBT.
+ *
+ * Return: 0 in case of success, a negative error code otherwise.
+ */
+int nanddev_bbt_init(struct nand_device *nand)
+{
+ unsigned int bits_per_block = fls(NAND_BBT_BLOCK_NUM_STATUS);
+ unsigned int nblocks = nanddev_neraseblocks(nand);
+
+ nand->bbt.cache = bitmap_zalloc(nblocks * bits_per_block, GFP_KERNEL);
+ if (!nand->bbt.cache)
+ return -ENOMEM;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(nanddev_bbt_init);
+
+/**
+ * nanddev_bbt_cleanup() - Cleanup the BBT (Bad Block Table)
+ * @nand: NAND device
+ *
+ * Undoes what has been done in nanddev_bbt_init()
+ */
+void nanddev_bbt_cleanup(struct nand_device *nand)
+{
+ bitmap_free(nand->bbt.cache);
+}
+EXPORT_SYMBOL_GPL(nanddev_bbt_cleanup);
+
+/**
+ * nanddev_bbt_update() - Update a BBT
+ * @nand: nand device
+ *
+ * Update the BBT. Currently a NOP function since on-flash bbt is not yet
+ * supported.
+ *
+ * Return: 0 in case of success, a negative error code otherwise.
+ */
+int nanddev_bbt_update(struct nand_device *nand)
+{
+ return 0;
+}
+EXPORT_SYMBOL_GPL(nanddev_bbt_update);
+
+/**
+ * nanddev_bbt_get_block_status() - Return the status of an eraseblock
+ * @nand: nand device
+ * @entry: the BBT entry
+ *
+ * Return: a positive number nand_bbt_block_status status or -%ERANGE if @entry
+ * is bigger than the BBT size.
+ */
+int nanddev_bbt_get_block_status(const struct nand_device *nand,
+ unsigned int entry)
+{
+ unsigned int bits_per_block = fls(NAND_BBT_BLOCK_NUM_STATUS);
+ unsigned long *pos = nand->bbt.cache +
+ ((entry * bits_per_block) / BITS_PER_LONG);
+ unsigned int offs = (entry * bits_per_block) % BITS_PER_LONG;
+ unsigned long status;
+
+ if (entry >= nanddev_neraseblocks(nand))
+ return -ERANGE;
+
+ status = pos[0] >> offs;
+ if (bits_per_block + offs > BITS_PER_LONG)
+ status |= pos[1] << (BITS_PER_LONG - offs);
+
+ return status & GENMASK(bits_per_block - 1, 0);
+}
+EXPORT_SYMBOL_GPL(nanddev_bbt_get_block_status);
+
+/**
+ * nanddev_bbt_set_block_status() - Update the status of an eraseblock in the
+ * in-memory BBT
+ * @nand: nand device
+ * @entry: the BBT entry to update
+ * @status: the new status
+ *
+ * Update an entry of the in-memory BBT. If you want to push the updated BBT
+ * the NAND you should call nanddev_bbt_update().
+ *
+ * Return: 0 in case of success or -%ERANGE if @entry is bigger than the BBT
+ * size.
+ */
+int nanddev_bbt_set_block_status(struct nand_device *nand, unsigned int entry,
+ enum nand_bbt_block_status status)
+{
+ unsigned int bits_per_block = fls(NAND_BBT_BLOCK_NUM_STATUS);
+ unsigned long *pos = nand->bbt.cache +
+ ((entry * bits_per_block) / BITS_PER_LONG);
+ unsigned int offs = (entry * bits_per_block) % BITS_PER_LONG;
+ unsigned long val = status & GENMASK(bits_per_block - 1, 0);
+
+ if (entry >= nanddev_neraseblocks(nand))
+ return -ERANGE;
+
+ pos[0] &= ~GENMASK(offs + bits_per_block - 1, offs);
+ pos[0] |= val << offs;
+
+ if (bits_per_block + offs > BITS_PER_LONG) {
+ unsigned int rbits = bits_per_block + offs - BITS_PER_LONG;
+
+ pos[1] &= ~GENMASK(rbits - 1, 0);
+ pos[1] |= val >> (bits_per_block - rbits);
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(nanddev_bbt_set_block_status);