Re: [PATCH 3/5] vfs: add a zero-initialization mode to fallocate
From: riteshh <hidden>
Date: 2021-09-18 16:58:28
Also in:
linux-fsdevel
On 21/09/17 06:31PM, Darrick J. Wong wrote:
From: Darrick J. Wong <djwong@kernel.org> Add a new mode to fallocate to zero-initialize all the storage backing a file.
This patch looks pretty straight forward to me. Thanks -ritesh
quoted hunk ↗ jump to hunk
Signed-off-by: Darrick J. Wong <djwong@kernel.org> --- fs/open.c | 5 +++++ include/linux/falloc.h | 1 + include/uapi/linux/falloc.h | 9 +++++++++ 3 files changed, 15 insertions(+)diff --git a/fs/open.c b/fs/open.c index daa324606a41..230220b8f67a 100644 --- a/fs/open.c +++ b/fs/open.c@@ -256,6 +256,11 @@ int vfs_fallocate(struct file *file, int mode, loff_t offset, loff_t len) (mode & ~FALLOC_FL_INSERT_RANGE)) return -EINVAL; + /* Zeroinit should only be used by itself and keep size must be set. */ + if ((mode & FALLOC_FL_ZEROINIT_RANGE) && + (mode != (FALLOC_FL_ZEROINIT_RANGE | FALLOC_FL_KEEP_SIZE))) + return -EINVAL; + /* Unshare range should only be used with allocate mode. */ if ((mode & FALLOC_FL_UNSHARE_RANGE) && (mode & ~(FALLOC_FL_UNSHARE_RANGE | FALLOC_FL_KEEP_SIZE)))diff --git a/include/linux/falloc.h b/include/linux/falloc.h index f3f0b97b1675..4597b416667b 100644 --- a/include/linux/falloc.h +++ b/include/linux/falloc.h@@ -29,6 +29,7 @@ struct space_resv { FALLOC_FL_PUNCH_HOLE | \ FALLOC_FL_COLLAPSE_RANGE | \ FALLOC_FL_ZERO_RANGE | \ + FALLOC_FL_ZEROINIT_RANGE | \ FALLOC_FL_INSERT_RANGE | \ FALLOC_FL_UNSHARE_RANGE)diff --git a/include/uapi/linux/falloc.h b/include/uapi/linux/falloc.h index 51398fa57f6c..8144403b6102 100644 --- a/include/uapi/linux/falloc.h +++ b/include/uapi/linux/falloc.h@@ -77,4 +77,13 @@ */ #define FALLOC_FL_UNSHARE_RANGE 0x40 +/* + * FALLOC_FL_ZEROINIT_RANGE is used to reinitialize storage backing a file by + * writing zeros to it. Subsequent read and writes should not fail due to any + * previous media errors. Blocks must be not be shared or require copy on + * write. Holes and unwritten extents are left untouched. This mode must be + * used with FALLOC_FL_KEEP_SIZE. + */ +#define FALLOC_FL_ZEROINIT_RANGE 0x80 + #endif /* _UAPI_FALLOC_H_ */