^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) * Copyright (C) 2001 Sistina Software (UK) Limited
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) * This file is released under the GPL.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) #include "dm-core.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/init.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/kmod.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <linux/bio.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #define DM_MSG_PREFIX "target"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) static LIST_HEAD(_targets);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) static DECLARE_RWSEM(_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) static inline struct target_type *__find_target_type(const char *name)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) struct target_type *tt;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) list_for_each_entry(tt, &_targets, list)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) if (!strcmp(name, tt->name))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) return tt;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) static struct target_type *get_target_type(const char *name)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) struct target_type *tt;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) down_read(&_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) tt = __find_target_type(name);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) if (tt && !try_module_get(tt->module))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) tt = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) up_read(&_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) return tt;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) static void load_module(const char *name)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) request_module("dm-%s", name);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) struct target_type *dm_get_target_type(const char *name)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) struct target_type *tt = get_target_type(name);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) if (!tt) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) load_module(name);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) tt = get_target_type(name);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) return tt;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) void dm_put_target_type(struct target_type *tt)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) down_read(&_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) module_put(tt->module);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) up_read(&_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) int dm_target_iterate(void (*iter_func)(struct target_type *tt,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) void *param), void *param)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) struct target_type *tt;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) down_read(&_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) list_for_each_entry(tt, &_targets, list)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) iter_func(tt, param);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) up_read(&_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) int dm_register_target(struct target_type *tt)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) int rv = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) down_write(&_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) if (__find_target_type(tt->name))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) rv = -EEXIST;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) list_add(&tt->list, &_targets);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) up_write(&_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) return rv;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) void dm_unregister_target(struct target_type *tt)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) down_write(&_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) if (!__find_target_type(tt->name)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) DMCRIT("Unregistering unrecognised target: %s", tt->name);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) BUG();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) list_del(&tt->list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) up_write(&_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) * io-err: always fails an io, useful for bringing
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) * up LVs that have holes in them.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) static int io_err_ctr(struct dm_target *tt, unsigned int argc, char **args)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) * Return error for discards instead of -EOPNOTSUPP
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) tt->num_discard_bios = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) static void io_err_dtr(struct dm_target *tt)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) /* empty */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) static int io_err_map(struct dm_target *tt, struct bio *bio)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) return DM_MAPIO_KILL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) static int io_err_clone_and_map_rq(struct dm_target *ti, struct request *rq,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) union map_info *map_context,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) struct request **clone)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) return DM_MAPIO_KILL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) static void io_err_release_clone_rq(struct request *clone,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) union map_info *map_context)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) static long io_err_dax_direct_access(struct dm_target *ti, pgoff_t pgoff,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) long nr_pages, void **kaddr, pfn_t *pfn)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) return -EIO;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) static struct target_type error_target = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) .name = "error",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) .version = {1, 5, 0},
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) .features = DM_TARGET_WILDCARD,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) .ctr = io_err_ctr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) .dtr = io_err_dtr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) .map = io_err_map,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) .clone_and_map_rq = io_err_clone_and_map_rq,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) .release_clone_rq = io_err_release_clone_rq,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) .direct_access = io_err_dax_direct_access,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) int __init dm_target_init(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) return dm_register_target(&error_target);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) void dm_target_exit(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) dm_unregister_target(&error_target);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) EXPORT_SYMBOL(dm_register_target);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) EXPORT_SYMBOL(dm_unregister_target);
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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