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