Add FIEMAP header file
PATCH 1/2 Add FIEMAP header file
Recently there was discussion about an "FIle Extent MAP"(FIEMAP) ioctl for efficiently mapping the extents and holes of a file. This will be many times more efficient than FIBMAP by cutting down the number of ioctls.
This patch adds the FIEMAP header file in include/linux.
Signed-off-by Andreas Dilger <[email protected]>
Signed-off-by Kalpak Shah <[email protected]>
include/linux/fiemap.h new file +49 -0
@@ -0,0 +1,49 @@ +/* +* include/linux/fiemap.h +* +* Copyright (C) 2007 Sun Microsystems, Inc. +* +* Author: Kalpak Shah <[email protected]> +* Andreas Dilger <[email protected]> +*/ + +#ifndef _LINUX_FIEMAP_H +#define _LINUX_FIEMAP_H + +struct fiemap_extent { +__u64 fe_offset;/* offset in bytes for the start of the extent */ +__u64 fe_length;/* length in bytes for the extent */ +__u32 fe_flags;/* returned FIEMAP_EXTENT_* flags for the extent */ +__u32 fe_lun;/* logical device number for extent (starting at 0)*/ +}; + +struct fiemap { +__u64 fm_start;/* logical starting byte offset (in/out) */ +__u64 fm_length;/* logical length of map (in/out) */ +__u32 fm_flags;/* FIEMAP_FLAG_* flags for request (in/out) */ +__u32 fm_extent_count;/* number of extents in fm_extents (in/out) */ +__u64 fm_end_offset;/* logical offset of end of mapping in last ioctl */ +struct fiemap_extent fm_extents[0 ]; +}; + +#define FIEMAP_FLAG_SYNC 0x00000001/* sync file data before map */ +#define FIEMAP_FLAG_HSM_READ 0x00000002/* get data from HSM before map */ +#define FIEMAP_FLAG_NUM_EXTENTS 0x00000004/* return only number of extents */ +#define FIEMAP_FLAG_INCOMPAT 0xff000000/* error for unknown flags in here */ + +#define FIEMAP_FLAG_LUN_OFFSET 0x01000000/* use lun offsets, instead of +* logical file offsets */ + +#define FIEMAP_EXTENT_HOLE 0x00000001/* has no data or space allocation */ +#define FIEMAP_EXTENT_UNWRITTEN 0x00000002/* space allocated, but no data */ +#define FIEMAP_EXTENT_UNMAPPED 0x00000004/* has data but no space allocation*/ +#define FIEMAP_EXTENT_ERROR 0x00000008/* mapping error, errno in fe_start*/ +#define FIEMAP_EXTENT_NO_DIRECT 0x00000010/* cannot access data directly */ +#define FIEMAP_EXTENT_LAST 0x00000020/* last extent in the file */ +#define FIEMAP_EXTENT_DELALLOC 0x00000040/* has data but not yet written, +* must have EXTENT_UNKNOWN set */ +#define FIEMAP_EXTENT_SECONDARY 0x00000080/* data (also) in secondary storage, +* not in primary if EXTENT_UNKNOWN*/ +#define FIEMAP_EXTENT_EOF 0x00000100/* if fm_start+fm_len is beyond EOF*/ + +#endif /* _LINUX_FIEMAP_H */
Quoted 3 lines · Kalpak Shah
Recently there was discussion about an "FIle Extent MAP"(FIEMAP) ioctl for efficiently mapping the extents and holes of a file. This will be many times more efficient than FIBMAP by cutting down the number of ioctls.
Thanks for sending this out.
Quoted 1 line
This patch adds the FIEMAP header file in
include/linux.
Any problem with defining the IOC_FIEMAP ioctl number in this header too? No EXT4 prefix so we keep things generic too, please.
--Mark
Quoted 48 lines
Signed-off-by Andreas Dilger <[email protected]>Signed-off-by Kalpak Shah <[email protected]>Index:
linux-2.6.23.1/include/linux/fiemap.h
===================================================================include/linux/fiemap.h new file +39
-0@@ -0,0 +1,49 @@ +/* +* include/linux/fiemap.h +* +* Copyright (C) 2007 Sun Microsystems, Inc. +* +* Author: Kalpak Shah <[email protected]> +* Andreas Dilger <[email protected]> +*/ + +#ifndef _LINUX_FIEMAP_H +#define _LINUX_FIEMAP_H + +struct fiemap_extent { +__u64 fe_offset;/* offset in bytes for the start of the extent */ +__u64 fe_length;/* length in bytes for the extent */ +__u32 fe_flags;/* returned FIEMAP_EXTENT_* flags for the extent */ +__u32 fe_lun;/* logical device number for extent (starting at 0)*/ +}; + +struct fiemap { +__u64 fm_start;/* logical starting byte offset (in/out) */ +__u64 fm_length;/* logical length of map (in/out) */ +__u32 fm_flags;/* FIEMAP_FLAG_* flags for request (in/out) */ +__u32 fm_extent_count;/* number of extents in fm_extents (in/out) */ +__u64 fm_end_offset;/* logical offset of end of mapping in last ioctl */ +struct fiemap_extent fm_extents[0 ]; +}; + +#define FIEMAP_FLAG_SYNC 0x00000001/* sync file data before map */ +#define FIEMAP_FLAG_HSM_READ 0x00000002/* get data from HSM before map */ +#define FIEMAP_FLAG_NUM_EXTENTS 0x00000004/* return only number of extents */ +#define FIEMAP_FLAG_INCOMPAT 0xff000000/* error for unknown flags in here */ + +#define FIEMAP_FLAG_LUN_OFFSET 0x01000000/* use lun offsets, instead of +* logical file offsets */ + +#define FIEMAP_EXTENT_HOLE 0x00000001/* has no data or space allocation */ +#define FIEMAP_EXTENT_UNWRITTEN 0x00000002/* space allocated, but no data */ +#define FIEMAP_EXTENT_UNMAPPED 0x00000004/* has data but no space allocation*/
include/linux/fiemap.h line 49
Quoted 10 lines
include/linux/fiemap.h new file +10
-0+#define FIEMAP_EXTENT_ERROR 0x00000008/* mapping error, errno in fe_start*/ +#define FIEMAP_EXTENT_NO_DIRECT 0x00000010/* cannot access data directly */ +#define FIEMAP_EXTENT_LAST 0x00000020/* last extent in the file */ +#define FIEMAP_EXTENT_DELALLOC 0x00000040/* has data but not yet written, +* must have EXTENT_UNKNOWN set */ +#define FIEMAP_EXTENT_SECONDARY 0x00000080/* data (also) in secondary storage, +* not in primary if EXTENT_UNKNOWN*/ +#define FIEMAP_EXTENT_EOF 0x00000100/* if fm_start+fm_len is beyond EOF*/ + +#endif /* _LINUX_FIEMAP_H */
--
Mark Fasheh
Senior Software Developer, Oracle
[email protected]