diff mbox series

[RFC,v4,07/11] fs: statx add write zeroes unmap attribute

Message ID 20250421021509.2366003-8-yi.zhang@huaweicloud.com
State New
Headers show
Series fallocate: introduce FALLOC_FL_WRITE_ZEROES flag | expand

Commit Message

Zhang Yi April 21, 2025, 2:15 a.m. UTC 
From: Zhang Yi <yi.zhang@huawei.com>

Add a new attribute flag to statx to determine whether a bdev or a file
supports the unmap write zeroes command.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
---
 block/bdev.c              | 4 ++++
 fs/ext4/inode.c           | 9 ++++++---
 include/uapi/linux/stat.h | 1 +
 3 files changed, 11 insertions(+), 3 deletions(-)
diff mbox series

Patch

diff --git a/block/bdev.c b/block/bdev.c
index 4844d1e27b6f..29b0e5feb138 100644
--- a/block/bdev.c
+++ b/block/bdev.c
@@ -1304,6 +1304,10 @@  void bdev_statx(struct path *path, struct kstat *stat,
 			queue_atomic_write_unit_max_bytes(bd_queue));
 	}
 
+	if (bdev_write_zeroes_unmap(bdev))
+		stat->attributes |= STATX_ATTR_WRITE_ZEROES_UNMAP;
+	stat->attributes_mask |= STATX_ATTR_WRITE_ZEROES_UNMAP;
+
 	stat->blksize = bdev_io_min(bdev);
 
 	blkdev_put_no_open(bdev);
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 94c7d2d828a6..38caf2f39c6d 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -5653,6 +5653,7 @@  int ext4_getattr(struct mnt_idmap *idmap, const struct path *path,
 	struct inode *inode = d_inode(path->dentry);
 	struct ext4_inode *raw_inode;
 	struct ext4_inode_info *ei = EXT4_I(inode);
+	struct block_device *bdev = inode->i_sb->s_bdev;
 	unsigned int flags;
 
 	if ((request_mask & STATX_BTIME) &&
@@ -5672,8 +5673,6 @@  int ext4_getattr(struct mnt_idmap *idmap, const struct path *path,
 
 		stat->result_mask |= STATX_DIOALIGN;
 		if (dio_align == 1) {
-			struct block_device *bdev = inode->i_sb->s_bdev;
-
 			/* iomap defaults */
 			stat->dio_mem_align = bdev_dma_alignment(bdev) + 1;
 			stat->dio_offset_align = bdev_logical_block_size(bdev);
@@ -5695,6 +5694,9 @@  int ext4_getattr(struct mnt_idmap *idmap, const struct path *path,
 		generic_fill_statx_atomic_writes(stat, awu_min, awu_max);
 	}
 
+	if (S_ISREG(inode->i_mode) && bdev_write_zeroes_unmap(bdev))
+		stat->attributes |= STATX_ATTR_WRITE_ZEROES_UNMAP;
+
 	flags = ei->i_flags & EXT4_FL_USER_VISIBLE;
 	if (flags & EXT4_APPEND_FL)
 		stat->attributes |= STATX_ATTR_APPEND;
@@ -5714,7 +5716,8 @@  int ext4_getattr(struct mnt_idmap *idmap, const struct path *path,
 				  STATX_ATTR_ENCRYPTED |
 				  STATX_ATTR_IMMUTABLE |
 				  STATX_ATTR_NODUMP |
-				  STATX_ATTR_VERITY);
+				  STATX_ATTR_VERITY |
+				  STATX_ATTR_WRITE_ZEROES_UNMAP);
 
 	generic_fillattr(idmap, request_mask, inode, stat);
 	return 0;
diff --git a/include/uapi/linux/stat.h b/include/uapi/linux/stat.h
index f78ee3670dd5..279ce7e34df7 100644
--- a/include/uapi/linux/stat.h
+++ b/include/uapi/linux/stat.h
@@ -251,6 +251,7 @@  struct statx {
 #define STATX_ATTR_VERITY		0x00100000 /* [I] Verity protected file */
 #define STATX_ATTR_DAX			0x00200000 /* File is currently in DAX state */
 #define STATX_ATTR_WRITE_ATOMIC		0x00400000 /* File supports atomic write operations */
+#define STATX_ATTR_WRITE_ZEROES_UNMAP	0x00800000 /* File supports unmap write zeroes */
 
 
 #endif /* _UAPI_LINUX_STAT_H */