[PATCH v4 06/10] fs/dax: Implement dax_holder_operations

Shiyang Ruan
2021-06-04T01:19:18Z

This is the case where the holder represents a filesystem. The offset
translation from disk to block device is needed before we calling
->corrupted_range().

When a specific filesystem is being mounted, we use dax_set_holder() to
associate it with the dax_device.

Signed-off-by: Shiyang Ruan <ruansy.fnst@fujitsu.com>
---
fs/dax.c | 16 ++++++++++++++++
include/linux/dax.h | 2 ++
2 files changed, 18 insertions(+)

diff --git a/fs/dax.c b/fs/dax.c
index 58faca85455a..1a7473f46df2 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -1762,3 +1762,19 @@ vm_fault_t dax_finish_sync_fault(struct vm_fault *vmf,
return dax_insert_pfn_mkwrite(vmf, pfn, order);
}
EXPORT_SYMBOL_GPL(dax_finish_sync_fault);
+
+static int fs_dax_corrupted_range(struct dax_device *dax_dev,
+ struct block_device *bdev, loff_t offset, size_t size,
+ void *data)
+{
+ struct super_block *sb = dax_get_holder(dax_dev);
+ loff_t bdev_off = offset - (get_start_sect(bdev) << SECTOR_SHIFT);
+
+ if (!sb->s_op->corrupted_range)
+ return -EOPNOTSUPP;
+ return sb->s_op->corrupted_range(sb, bdev, bdev_off, size, data);
+}
+
+const struct dax_holder_operations fs_dax_holder_ops = {
+ .corrupted_range = fs_dax_corrupted_range,
+};
\ No newline at end of file
diff --git a/include/linux/dax.h b/include/linux/dax.h
index 6e758daa5004..b35b3b8959a5 100644
--- a/include/linux/dax.h
+++ b/include/linux/dax.h
@@ -254,6 +254,8 @@ static inline bool dax_mapping(struct address_space *mapping)
return mapping->host && IS_DAX(mapping->host);
}

+extern const struct dax_holder_operations fs_dax_holder_ops;
+
#ifdef CONFIG_DEV_DAX_HMEM_DEVICES
void hmem_register_device(int target_nid, struct resource *r);
#else
--
2.31.1