1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux << 2 #ifndef _UAPI_FALLOC_H_ 1 #ifndef _UAPI_FALLOC_H_ 3 #define _UAPI_FALLOC_H_ 2 #define _UAPI_FALLOC_H_ 4 3 5 #define FALLOC_FL_ALLOCATE_RANGE 0x00 /* alloc << 6 #define FALLOC_FL_KEEP_SIZE 0x01 /* defaul 4 #define FALLOC_FL_KEEP_SIZE 0x01 /* default is extend size */ 7 #define FALLOC_FL_PUNCH_HOLE 0x02 /* de-all 5 #define FALLOC_FL_PUNCH_HOLE 0x02 /* de-allocates range */ 8 #define FALLOC_FL_NO_HIDE_STALE 0x04 /* reserv 6 #define FALLOC_FL_NO_HIDE_STALE 0x04 /* reserved codepoint */ 9 7 10 /* 8 /* 11 * FALLOC_FL_COLLAPSE_RANGE is used to remove 9 * FALLOC_FL_COLLAPSE_RANGE is used to remove a range of a file 12 * without leaving a hole in the file. The con 10 * without leaving a hole in the file. The contents of the file beyond 13 * the range being removed is appended to the 11 * the range being removed is appended to the start offset of the range 14 * being removed (i.e. the hole that was punch 12 * being removed (i.e. the hole that was punched is "collapsed"), 15 * resulting in a file layout that looks like 13 * resulting in a file layout that looks like the range that was 16 * removed never existed. As such collapsing a 14 * removed never existed. As such collapsing a range of a file changes 17 * the size of the file, reducing it by the sa 15 * the size of the file, reducing it by the same length of the range 18 * that has been removed by the operation. 16 * that has been removed by the operation. 19 * 17 * 20 * Different filesystems may implement differe 18 * Different filesystems may implement different limitations on the 21 * granularity of the operation. Most will lim 19 * granularity of the operation. Most will limit operations to 22 * filesystem block size boundaries, but this 20 * filesystem block size boundaries, but this boundary may be larger or 23 * smaller depending on the filesystem and/or 21 * smaller depending on the filesystem and/or the configuration of the 24 * filesystem or file. 22 * filesystem or file. 25 * 23 * 26 * Attempting to collapse a range that crosses 24 * Attempting to collapse a range that crosses the end of the file is 27 * considered an illegal operation - just use 25 * considered an illegal operation - just use ftruncate(2) if you need 28 * to collapse a range that crosses EOF. 26 * to collapse a range that crosses EOF. 29 */ 27 */ 30 #define FALLOC_FL_COLLAPSE_RANGE 0x08 28 #define FALLOC_FL_COLLAPSE_RANGE 0x08 31 29 32 /* 30 /* 33 * FALLOC_FL_ZERO_RANGE is used to convert a r 31 * FALLOC_FL_ZERO_RANGE is used to convert a range of file to zeros preferably 34 * without issuing data IO. Blocks should be p 32 * without issuing data IO. Blocks should be preallocated for the regions that 35 * span holes in the file, and the entire rang 33 * span holes in the file, and the entire range is preferable converted to 36 * unwritten extents - even though file system 34 * unwritten extents - even though file system may choose to zero out the 37 * extent or do whatever which will result in 35 * extent or do whatever which will result in reading zeros from the range 38 * while the range remains allocated for the f 36 * while the range remains allocated for the file. 39 * 37 * 40 * This can be also used to preallocate blocks 38 * This can be also used to preallocate blocks past EOF in the same way as 41 * with fallocate. Flag FALLOC_FL_KEEP_SIZE sh 39 * with fallocate. Flag FALLOC_FL_KEEP_SIZE should cause the inode 42 * size to remain the same. 40 * size to remain the same. 43 */ 41 */ 44 #define FALLOC_FL_ZERO_RANGE 0x10 42 #define FALLOC_FL_ZERO_RANGE 0x10 45 43 46 /* 44 /* 47 * FALLOC_FL_INSERT_RANGE is use to insert spa 45 * FALLOC_FL_INSERT_RANGE is use to insert space within the file size without 48 * overwriting any existing data. The contents 46 * overwriting any existing data. The contents of the file beyond offset are 49 * shifted towards right by len bytes to creat 47 * shifted towards right by len bytes to create a hole. As such, this 50 * operation will increase the size of the fil 48 * operation will increase the size of the file by len bytes. 51 * 49 * 52 * Different filesystems may implement differe 50 * Different filesystems may implement different limitations on the granularity 53 * of the operation. Most will limit operation 51 * of the operation. Most will limit operations to filesystem block size 54 * boundaries, but this boundary may be larger 52 * boundaries, but this boundary may be larger or smaller depending on 55 * the filesystem and/or the configuration of 53 * the filesystem and/or the configuration of the filesystem or file. 56 * 54 * 57 * Attempting to insert space using this flag 55 * Attempting to insert space using this flag at OR beyond the end of 58 * the file is considered an illegal operation 56 * the file is considered an illegal operation - just use ftruncate(2) or 59 * fallocate(2) with mode 0 for such type of o 57 * fallocate(2) with mode 0 for such type of operations. 60 */ 58 */ 61 #define FALLOC_FL_INSERT_RANGE 0x20 59 #define FALLOC_FL_INSERT_RANGE 0x20 62 60 63 /* 61 /* 64 * FALLOC_FL_UNSHARE_RANGE is used to unshare 62 * FALLOC_FL_UNSHARE_RANGE is used to unshare shared blocks within the 65 * file size without overwriting any existing 63 * file size without overwriting any existing data. The purpose of this 66 * call is to preemptively reallocate any bloc 64 * call is to preemptively reallocate any blocks that are subject to 67 * copy-on-write. 65 * copy-on-write. 68 * 66 * 69 * Different filesystems may implement differe 67 * Different filesystems may implement different limitations on the 70 * granularity of the operation. Most will lim 68 * granularity of the operation. Most will limit operations to filesystem 71 * block size boundaries, but this boundary ma 69 * block size boundaries, but this boundary may be larger or smaller 72 * depending on the filesystem and/or the conf 70 * depending on the filesystem and/or the configuration of the filesystem 73 * or file. 71 * or file. 74 * 72 * 75 * This flag can only be used with allocate-mo 73 * This flag can only be used with allocate-mode fallocate, which is 76 * to say that it cannot be used with the punc 74 * to say that it cannot be used with the punch, zero, collapse, or 77 * insert range modes. 75 * insert range modes. 78 */ 76 */ 79 #define FALLOC_FL_UNSHARE_RANGE 0x40 77 #define FALLOC_FL_UNSHARE_RANGE 0x40 80 78 81 #endif /* _UAPI_FALLOC_H_ */ 79 #endif /* _UAPI_FALLOC_H_ */ 82 80
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