1 // SPDX-License-Identifier: CDDL-1.0 2 /* 3 * This file and its contents are supplied under the terms of the 4 * Common Development and Distribution License ("CDDL"), version 1.0. 5 * You may only use this file in accordance with the terms of version 6 * 1.0 of the CDDL. 7 * 8 * A full copy of the text of the CDDL should have accompanied this 9 * source. A copy of the CDDL is also available via the Internet at 10 * https://opensource.org/license/CDDL-1.0. 11 */ 12 /* 13 * Copyright (c) 2024, 2025, Klara, Inc. 14 */ 15 16 #ifndef _SYS_ZVOL_IMPL_H 17 #define _SYS_ZVOL_IMPL_H 18 19 #include <sys/zfs_context.h> 20 21 #define ZVOL_RDONLY (1<<0) /* zvol is readonly (writes rejected) */ 22 #define ZVOL_WRITTEN_TO (1<<1) /* zvol has been written to (needs flush) */ 23 #define ZVOL_EXCL (1<<2) /* zvol has O_EXCL client right now */ 24 #define ZVOL_REMOVING (1<<3) /* zvol waiting to remove minor */ 25 26 /* 27 * The in-core state of each volume. 28 */ 29 typedef struct zvol_state { 30 char zv_name[MAXNAMELEN]; /* name */ 31 uint64_t zv_volsize; /* advertised space */ 32 uint64_t zv_volblocksize; /* volume block size */ 33 objset_t *zv_objset; /* objset handle */ 34 uint32_t zv_flags; /* ZVOL_* flags */ 35 uint32_t zv_open_count; /* open counts */ 36 uint32_t zv_changed; /* disk changed */ 37 uint32_t zv_volmode; /* volmode */ 38 zilog_t *zv_zilog; /* ZIL handle */ 39 zfs_rangelock_t zv_rangelock; /* for range locking */ 40 dnode_t *zv_dn; /* dnode hold */ 41 dataset_kstats_t zv_kstat; /* zvol kstats */ 42 list_node_t zv_next; /* next zvol_state_t linkage */ 43 uint64_t zv_hash; /* name hash */ 44 struct hlist_node zv_hlink; /* hash link */ 45 kmutex_t zv_state_lock; /* protects zvol_state_t */ 46 atomic_t zv_suspend_ref; /* refcount for suspend */ 47 krwlock_t zv_suspend_lock; /* suspend lock */ 48 kcondvar_t zv_removing_cv; /* ready to remove minor */ 49 list_node_t zv_remove_node; /* node on removal list */ 50 struct zvol_state_os *zv_zso; /* private platform state */ 51 boolean_t zv_threading; /* volthreading property */ 52 } zvol_state_t; 53 54 /* 55 * zvol taskqs 56 */ 57 typedef struct zv_taskq { 58 uint_t tqs_cnt; 59 taskq_t **tqs_taskq; 60 } zv_taskq_t; 61 62 typedef struct zv_request_stack { 63 zvol_state_t *zv; 64 struct bio *bio; 65 #ifdef __linux__ 66 struct request *rq; 67 #endif 68 } zv_request_t; 69 70 typedef struct zv_request_task { 71 zv_request_t zvr; 72 taskq_ent_t ent; 73 } zv_request_task_t; 74 75 /* 76 * Switch taskq at multiple of 512 MB offset. This can be set to a lower value 77 * to utilize more threads for small files but may affect prefetch hits. 78 */ 79 #define ZVOL_TASKQ_OFFSET_SHIFT 29 80 81 extern krwlock_t zvol_state_lock; 82 #define ZVOL_HT_SIZE 1024 83 extern struct hlist_head *zvol_htable; 84 #define ZVOL_HT_HEAD(hash) (&zvol_htable[(hash) & (ZVOL_HT_SIZE-1)]) 85 extern zil_replay_func_t *const zvol_replay_vector[TX_MAX_TYPE]; 86 87 extern unsigned int zvol_inhibit_dev; 88 extern unsigned int zvol_prefetch_bytes; 89 extern unsigned int zvol_volmode; 90 extern unsigned int zvol_threads; 91 extern unsigned int zvol_num_taskqs; 92 extern unsigned int zvol_request_sync; 93 extern zv_taskq_t zvol_taskqs; 94 95 /* 96 * platform independent functions exported to platform code 97 */ 98 zvol_state_t *zvol_find_by_name_hash(const char *name, 99 uint64_t hash, int mode); 100 int zvol_first_open(zvol_state_t *zv, boolean_t readonly); 101 uint64_t zvol_name_hash(const char *name); 102 void zvol_last_close(zvol_state_t *zv); 103 void zvol_insert(zvol_state_t *zv); 104 void zvol_log_truncate(zvol_state_t *zv, dmu_tx_t *tx, uint64_t off, 105 uint64_t len); 106 void zvol_log_write(zvol_state_t *zv, dmu_tx_t *tx, uint64_t offset, 107 uint64_t size, boolean_t commit); 108 int zvol_get_data(void *arg, uint64_t arg2, lr_write_t *lr, char *buf, 109 struct lwb *lwb, zio_t *zio); 110 int zvol_init_impl(void); 111 void zvol_fini_impl(void); 112 void zvol_wait_close(zvol_state_t *zv); 113 int zvol_clone_range(zvol_state_handle_t *, uint64_t, 114 zvol_state_handle_t *, uint64_t, uint64_t); 115 void zvol_log_clone_range(zilog_t *zilog, dmu_tx_t *tx, int txtype, 116 uint64_t off, uint64_t len, uint64_t blksz, const blkptr_t *bps, 117 size_t nbps); 118 zv_request_task_t *zv_request_task_create(zv_request_t zvr); 119 void zv_request_task_free(zv_request_task_t *task); 120 121 /* 122 * platform dependent functions exported to platform independent code 123 */ 124 void zvol_os_free(zvol_state_t *zv); 125 int zvol_os_rename_minor(zvol_state_t *zv, const char *newname); 126 int zvol_os_create_minor(const char *name); 127 int zvol_os_update_volsize(zvol_state_t *zv, uint64_t volsize); 128 boolean_t zvol_os_is_zvol(const char *path); 129 void zvol_os_remove_minor(zvol_state_t *zv); 130 void zvol_os_set_disk_ro(zvol_state_t *zv, int flags); 131 void zvol_os_set_capacity(zvol_state_t *zv, uint64_t capacity); 132 133 #endif 134