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authorDapeng Mi <dapeng1.mi@linux.intel.com>2026-09-17 09:52:33 +0800
committerIngo Molnar <mingo@kernel.org>2026-09-22 11:37:46 +0200
commit0102c8c7fdfc4bd700971daff2b94470f4eafae4 (patch)
tree531306c2299f9a269f0a986e29f17ba972180104 /fs/ntfs/bdev-io.c
downloadlinux-stable-0102c8c7fdfc4bd700971daff2b94470f4eafae4.tar.gz
linux-stable-0102c8c7fdfc4bd700971daff2b94470f4eafae4.zip
perf/x86/intel: Rename DMR offcore_rsp attribute to offmodule_rspgrafted
DMR introduces Offmodule Response events in place of the legacy Offcore Response events, but it still exposes the inherited offcore_rsp PMU attribute for programming the corresponding MSR data. Rename the DMR PMU attribute to offmodule_rsp so the sysfs interface matches the underlying event name and avoids user & tooling confusion. Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://patch.msgid.link/20260917015234.981153-12-dapeng1.mi@linux.intel.com
Diffstat (limited to 'fs/ntfs/bdev-io.c')
-rw-r--r--fs/ntfs/bdev-io.c120
1 files changed, 120 insertions, 0 deletions
diff --git a/fs/ntfs/bdev-io.c b/fs/ntfs/bdev-io.c
new file mode 100644
index 000000000..4f27eed3b
--- /dev/null
+++ b/fs/ntfs/bdev-io.c
@@ -0,0 +1,120 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * NTFS block device I/O.
+ *
+ * Copyright (c) 2026 LG Electronics Co., Ltd.
+ */
+
+#include <linux/blkdev.h>
+
+#include "ntfs.h"
+
+/*
+ * ntfs_bdev_read - Read data directly from block device using bio
+ * @bdev: block device to read from
+ * @data: destination buffer
+ * @start: starting byte offset on the block device
+ * @size: number of bytes to read
+ *
+ * Reads @size bytes starting from byte offset @start directly from the block
+ * device using one or more BIOs. This function bypasses the page cache
+ * completely and performs synchronous I/O with REQ_META | REQ_SYNC flags set.
+ *
+ * The @start offset must be sector-aligned (512 bytes). If it is not aligned,
+ * the function will return -EINVAL.
+ *
+ * If the destination buffer @data is not a vmalloc address, it falls back
+ * to the more efficient bdev_rw_virt() helper.
+ *
+ * Return: 0 on success, negative error code on failure.
+ */
+int ntfs_bdev_read(struct block_device *bdev, char *data, loff_t start, size_t size)
+{
+ unsigned int done = 0, added;
+ int error;
+ struct bio *bio;
+ blk_opf_t op;
+ sector_t sector = ntfs_bytes_to_bio_sector(start);
+
+ if (start & (SECTOR_SIZE - 1))
+ return -EINVAL;
+
+ op = REQ_OP_READ | REQ_META | REQ_SYNC;
+ if (!is_vmalloc_addr(data))
+ return bdev_rw_virt(bdev, sector, data, size, op);
+
+ bio = bio_alloc(bdev,
+ bio_max_segs(DIV_ROUND_UP(size, PAGE_SIZE)),
+ op, GFP_KERNEL);
+ bio->bi_iter.bi_sector = sector;
+
+ do {
+ added = bio_add_vmalloc_chunk(bio, data + done, size - done);
+ if (!added) {
+ struct bio *prev = bio;
+
+ bio = bio_alloc(prev->bi_bdev,
+ bio_max_segs(DIV_ROUND_UP(size - done, PAGE_SIZE)),
+ prev->bi_opf, GFP_KERNEL);
+ bio->bi_iter.bi_sector = bio_end_sector(prev);
+ bio_chain(prev, bio);
+ submit_bio(prev);
+ }
+ done += added;
+ } while (done < size);
+
+ error = submit_bio_wait(bio);
+ bio_put(bio);
+
+ if ((op & REQ_OP_MASK) == REQ_OP_READ)
+ invalidate_kernel_vmap_range(data, size);
+ return error;
+}
+
+/*
+ * ntfs_bdev_write - Update block device contents via page cache
+ * @sb: super block of the mounted NTFS filesystem
+ * @buf: source buffer containing data to write
+ * @start: starting byte offset on the block device
+ * @size: number of bytes to write
+ *
+ * Writes @size bytes from @buf to the block device (sb->s_bdev) starting
+ * at byte offset @start. The write is performed entirely through the page
+ * cache of the block device's address space.
+ */
+int ntfs_bdev_write(struct super_block *sb, void *buf, loff_t start, size_t size)
+{
+ pgoff_t idx, idx_end;
+ loff_t offset, end = start + size;
+ u32 from, to, buf_off = 0;
+ struct folio *folio;
+
+ idx = start >> PAGE_SHIFT;
+ idx_end = end >> PAGE_SHIFT;
+ from = start & ~PAGE_MASK;
+
+ if (idx == idx_end)
+ idx_end++;
+
+ for (; idx < idx_end; idx++, from = 0) {
+ u32 len;
+
+ folio = read_mapping_folio(sb->s_bdev->bd_mapping, idx, NULL);
+ if (IS_ERR(folio)) {
+ ntfs_error(sb, "Unable to read %ld page", idx);
+ return PTR_ERR(folio);
+ }
+
+ offset = (loff_t)idx << PAGE_SHIFT;
+ to = min_t(u32, end - offset, PAGE_SIZE);
+ len = to - from;
+
+ memcpy_to_folio(folio, from, buf + buf_off, len);
+ buf_off += len;
+ folio_mark_uptodate(folio);
+ folio_mark_dirty(folio);
+ folio_put(folio);
+ }
+
+ return 0;
+}