1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2007 Sun Microsystems, Inc. 23 * All rights reserved. Use is subject to license terms. 24 */ 25 26 #ifndef _SYS_FS_TMP_H 27 #define _SYS_FS_TMP_H 28 29 #pragma ident "%Z%%M% %I% %E% SMI" 30 31 #ifdef __cplusplus 32 extern "C" { 33 #endif 34 35 /* 36 * tmpfs per-mount data structure. 37 * 38 * All fields are protected by tm_contents. 39 * File renames on a particular file system are protected tm_renamelck. 40 */ 41 struct tmount { 42 struct vfs *tm_vfsp; /* filesystem's vfs struct */ 43 struct tmpnode *tm_rootnode; /* root tmpnode */ 44 char *tm_mntpath; /* name of tmpfs mount point */ 45 ulong_t tm_anonmax; /* file system max anon reservation */ 46 pgcnt_t tm_anonmem; /* pages of reserved anon memory */ 47 dev_t tm_dev; /* unique dev # of mounted `device' */ 48 uint_t tm_gen; /* pseudo generation number for files */ 49 kmutex_t tm_contents; /* lock for tmount structure */ 50 kmutex_t tm_renamelck; /* rename lock for this mount */ 51 }; 52 53 /* 54 * File system independent to tmpfs conversion macros 55 */ 56 #define VFSTOTM(vfsp) ((struct tmount *)(vfsp)->vfs_data) 57 #define VTOTM(vp) ((struct tmount *)(vp)->v_vfsp->vfs_data) 58 #define VTOTN(vp) ((struct tmpnode *)(vp)->v_data) 59 #define TNTOV(tp) ((tp)->tn_vnode) 60 #define tmpnode_hold(tp) VN_HOLD(TNTOV(tp)) 61 #define tmpnode_rele(tp) VN_RELE(TNTOV(tp)) 62 63 /* 64 * enums 65 */ 66 enum de_op { DE_CREATE, DE_MKDIR, DE_LINK, DE_RENAME }; /* direnter ops */ 67 enum dr_op { DR_REMOVE, DR_RMDIR, DR_RENAME }; /* dirremove ops */ 68 69 /* 70 * tmpfs_minfree is the amount (in pages) of anonymous memory that tmpfs 71 * leaves free for the rest of the system. E.g. in a system with 32MB of 72 * configured swap space, if 16MB were reserved (leaving 16MB free), 73 * tmpfs could allocate up to 16MB - tmpfs_minfree. The default value 74 * for tmpfs_minfree is btopr(TMPMINFREE) but it can cautiously patched 75 * to a different number of pages. 76 * NB: If tmpfs allocates too much swap space, other processes will be 77 * unable to execute. 78 */ 79 #define TMPMINFREE 2 * 1024 * 1024 /* 2 Megabytes */ 80 81 extern size_t tmpfs_minfree; /* Anonymous memory in pages */ 82 83 /* 84 * tmpfs can allocate only a certain percentage of kernel memory, 85 * which is used for tmpnodes, directories, file names, etc. 86 * This is statically set as TMPMAXFRACKMEM of physical memory. 87 * The actual number of allocatable bytes can be patched in tmpfs_maxkmem. 88 */ 89 #define TMPMAXFRACKMEM 25 /* 1/25 of physical memory */ 90 91 extern size_t tmp_kmemspace; 92 extern size_t tmpfs_maxkmem; /* Allocatable kernel memory in bytes */ 93 94 extern void tmpnode_init(struct tmount *, struct tmpnode *, 95 struct vattr *, struct cred *); 96 extern int tmpnode_trunc(struct tmount *, struct tmpnode *, ulong_t); 97 extern void tmpnode_growmap(struct tmpnode *, ulong_t); 98 extern int tdirlookup(struct tmpnode *, char *, struct tmpnode **, 99 struct cred *); 100 extern int tdirdelete(struct tmpnode *, struct tmpnode *, char *, 101 enum dr_op, struct cred *); 102 extern void tdirinit(struct tmpnode *, struct tmpnode *); 103 extern void tdirtrunc(struct tmpnode *); 104 extern void *tmp_memalloc(size_t, int); 105 extern void tmp_memfree(void *, size_t); 106 extern int tmp_resv(struct tmount *, struct tmpnode *, size_t, int); 107 extern int tmp_taccess(void *, int, struct cred *); 108 extern int tmp_sticky_remove_access(struct tmpnode *, struct tmpnode *, 109 struct cred *); 110 extern int tmp_convnum(char *, pgcnt_t *); 111 extern int tdirenter(struct tmount *, struct tmpnode *, char *, 112 enum de_op, struct tmpnode *, struct tmpnode *, struct vattr *, 113 struct tmpnode **, struct cred *, caller_context_t *); 114 115 #define TMP_MUSTHAVE 0x01 116 117 #ifdef __cplusplus 118 } 119 #endif 120 121 #endif /* _SYS_FS_TMP_H */ 122