David Teigland | 597d0ca | 2006-07-12 16:44:04 -0500 | [diff] [blame] | 1 | /* |
David Teigland | ef0c2bb | 2007-03-28 09:56:46 -0500 | [diff] [blame] | 2 | * Copyright (C) 2006-2007 Red Hat, Inc. All rights reserved. |
David Teigland | 597d0ca | 2006-07-12 16:44:04 -0500 | [diff] [blame] | 3 | * |
| 4 | * This copyrighted material is made available to anyone wishing to use, |
| 5 | * modify, copy, or redistribute it subject to the terms and conditions |
| 6 | * of the GNU General Public License v.2. |
| 7 | */ |
| 8 | |
| 9 | #include <linux/miscdevice.h> |
| 10 | #include <linux/init.h> |
| 11 | #include <linux/wait.h> |
| 12 | #include <linux/module.h> |
| 13 | #include <linux/file.h> |
| 14 | #include <linux/fs.h> |
| 15 | #include <linux/poll.h> |
| 16 | #include <linux/signal.h> |
| 17 | #include <linux/spinlock.h> |
| 18 | #include <linux/dlm.h> |
| 19 | #include <linux/dlm_device.h> |
| 20 | |
| 21 | #include "dlm_internal.h" |
| 22 | #include "lockspace.h" |
| 23 | #include "lock.h" |
| 24 | #include "lvb_table.h" |
Adrian Bunk | 84c6e8c | 2007-02-26 00:18:42 +0100 | [diff] [blame] | 25 | #include "user.h" |
David Teigland | 597d0ca | 2006-07-12 16:44:04 -0500 | [diff] [blame] | 26 | |
| 27 | static const char *name_prefix="dlm"; |
| 28 | static struct miscdevice ctl_device; |
Arjan van de Ven | 00977a5 | 2007-02-12 00:55:34 -0800 | [diff] [blame] | 29 | static const struct file_operations device_fops; |
David Teigland | 597d0ca | 2006-07-12 16:44:04 -0500 | [diff] [blame] | 30 | |
| 31 | #ifdef CONFIG_COMPAT |
| 32 | |
| 33 | struct dlm_lock_params32 { |
| 34 | __u8 mode; |
| 35 | __u8 namelen; |
| 36 | __u16 flags; |
| 37 | __u32 lkid; |
| 38 | __u32 parent; |
| 39 | |
| 40 | __u32 castparam; |
| 41 | __u32 castaddr; |
| 42 | __u32 bastparam; |
| 43 | __u32 bastaddr; |
| 44 | __u32 lksb; |
| 45 | |
| 46 | char lvb[DLM_USER_LVB_LEN]; |
| 47 | char name[0]; |
| 48 | }; |
| 49 | |
| 50 | struct dlm_write_request32 { |
| 51 | __u32 version[3]; |
| 52 | __u8 cmd; |
| 53 | __u8 is64bit; |
| 54 | __u8 unused[2]; |
| 55 | |
| 56 | union { |
| 57 | struct dlm_lock_params32 lock; |
| 58 | struct dlm_lspace_params lspace; |
David Teigland | 72c2be7 | 2007-03-30 15:06:16 -0500 | [diff] [blame^] | 59 | struct dlm_purge_params purge; |
David Teigland | 597d0ca | 2006-07-12 16:44:04 -0500 | [diff] [blame] | 60 | } i; |
| 61 | }; |
| 62 | |
| 63 | struct dlm_lksb32 { |
| 64 | __u32 sb_status; |
| 65 | __u32 sb_lkid; |
| 66 | __u8 sb_flags; |
| 67 | __u32 sb_lvbptr; |
| 68 | }; |
| 69 | |
| 70 | struct dlm_lock_result32 { |
| 71 | __u32 length; |
| 72 | __u32 user_astaddr; |
| 73 | __u32 user_astparam; |
| 74 | __u32 user_lksb; |
| 75 | struct dlm_lksb32 lksb; |
| 76 | __u8 bast_mode; |
| 77 | __u8 unused[3]; |
| 78 | /* Offsets may be zero if no data is present */ |
| 79 | __u32 lvb_offset; |
| 80 | }; |
| 81 | |
| 82 | static void compat_input(struct dlm_write_request *kb, |
| 83 | struct dlm_write_request32 *kb32) |
| 84 | { |
| 85 | kb->version[0] = kb32->version[0]; |
| 86 | kb->version[1] = kb32->version[1]; |
| 87 | kb->version[2] = kb32->version[2]; |
| 88 | |
| 89 | kb->cmd = kb32->cmd; |
| 90 | kb->is64bit = kb32->is64bit; |
| 91 | if (kb->cmd == DLM_USER_CREATE_LOCKSPACE || |
| 92 | kb->cmd == DLM_USER_REMOVE_LOCKSPACE) { |
| 93 | kb->i.lspace.flags = kb32->i.lspace.flags; |
| 94 | kb->i.lspace.minor = kb32->i.lspace.minor; |
| 95 | strcpy(kb->i.lspace.name, kb32->i.lspace.name); |
David Teigland | 72c2be7 | 2007-03-30 15:06:16 -0500 | [diff] [blame^] | 96 | } else if (kb->cmd == DLM_USER_PURGE) { |
| 97 | kb->i.purge.nodeid = kb32->i.purge.nodeid; |
| 98 | kb->i.purge.pid = kb32->i.purge.pid; |
David Teigland | 597d0ca | 2006-07-12 16:44:04 -0500 | [diff] [blame] | 99 | } else { |
| 100 | kb->i.lock.mode = kb32->i.lock.mode; |
| 101 | kb->i.lock.namelen = kb32->i.lock.namelen; |
| 102 | kb->i.lock.flags = kb32->i.lock.flags; |
| 103 | kb->i.lock.lkid = kb32->i.lock.lkid; |
| 104 | kb->i.lock.parent = kb32->i.lock.parent; |
| 105 | kb->i.lock.castparam = (void *)(long)kb32->i.lock.castparam; |
| 106 | kb->i.lock.castaddr = (void *)(long)kb32->i.lock.castaddr; |
| 107 | kb->i.lock.bastparam = (void *)(long)kb32->i.lock.bastparam; |
| 108 | kb->i.lock.bastaddr = (void *)(long)kb32->i.lock.bastaddr; |
| 109 | kb->i.lock.lksb = (void *)(long)kb32->i.lock.lksb; |
| 110 | memcpy(kb->i.lock.lvb, kb32->i.lock.lvb, DLM_USER_LVB_LEN); |
| 111 | memcpy(kb->i.lock.name, kb32->i.lock.name, kb->i.lock.namelen); |
| 112 | } |
| 113 | } |
| 114 | |
| 115 | static void compat_output(struct dlm_lock_result *res, |
| 116 | struct dlm_lock_result32 *res32) |
| 117 | { |
| 118 | res32->length = res->length - (sizeof(struct dlm_lock_result) - |
| 119 | sizeof(struct dlm_lock_result32)); |
| 120 | res32->user_astaddr = (__u32)(long)res->user_astaddr; |
| 121 | res32->user_astparam = (__u32)(long)res->user_astparam; |
| 122 | res32->user_lksb = (__u32)(long)res->user_lksb; |
| 123 | res32->bast_mode = res->bast_mode; |
| 124 | |
| 125 | res32->lvb_offset = res->lvb_offset; |
| 126 | res32->length = res->length; |
| 127 | |
| 128 | res32->lksb.sb_status = res->lksb.sb_status; |
| 129 | res32->lksb.sb_flags = res->lksb.sb_flags; |
| 130 | res32->lksb.sb_lkid = res->lksb.sb_lkid; |
| 131 | res32->lksb.sb_lvbptr = (__u32)(long)res->lksb.sb_lvbptr; |
| 132 | } |
| 133 | #endif |
| 134 | |
David Teigland | ef0c2bb | 2007-03-28 09:56:46 -0500 | [diff] [blame] | 135 | /* we could possibly check if the cancel of an orphan has resulted in the lkb |
| 136 | being removed and then remove that lkb from the orphans list and free it */ |
David Teigland | 597d0ca | 2006-07-12 16:44:04 -0500 | [diff] [blame] | 137 | |
| 138 | void dlm_user_add_ast(struct dlm_lkb *lkb, int type) |
| 139 | { |
| 140 | struct dlm_ls *ls; |
| 141 | struct dlm_user_args *ua; |
| 142 | struct dlm_user_proc *proc; |
David Teigland | ef0c2bb | 2007-03-28 09:56:46 -0500 | [diff] [blame] | 143 | int eol = 0, ast_type; |
David Teigland | 597d0ca | 2006-07-12 16:44:04 -0500 | [diff] [blame] | 144 | |
David Teigland | ef0c2bb | 2007-03-28 09:56:46 -0500 | [diff] [blame] | 145 | if (lkb->lkb_flags & (DLM_IFL_ORPHAN | DLM_IFL_DEAD)) |
David Teigland | 597d0ca | 2006-07-12 16:44:04 -0500 | [diff] [blame] | 146 | return; |
David Teigland | 597d0ca | 2006-07-12 16:44:04 -0500 | [diff] [blame] | 147 | |
| 148 | ls = lkb->lkb_resource->res_ls; |
| 149 | mutex_lock(&ls->ls_clear_proc_locks); |
| 150 | |
| 151 | /* If ORPHAN/DEAD flag is set, it means the process is dead so an ast |
| 152 | can't be delivered. For ORPHAN's, dlm_clear_proc_locks() freed |
David Teigland | ef0c2bb | 2007-03-28 09:56:46 -0500 | [diff] [blame] | 153 | lkb->ua so we can't try to use it. This second check is necessary |
| 154 | for cases where a completion ast is received for an operation that |
| 155 | began before clear_proc_locks did its cancel/unlock. */ |
David Teigland | 597d0ca | 2006-07-12 16:44:04 -0500 | [diff] [blame] | 156 | |
David Teigland | ef0c2bb | 2007-03-28 09:56:46 -0500 | [diff] [blame] | 157 | if (lkb->lkb_flags & (DLM_IFL_ORPHAN | DLM_IFL_DEAD)) |
David Teigland | 597d0ca | 2006-07-12 16:44:04 -0500 | [diff] [blame] | 158 | goto out; |
David Teigland | 597d0ca | 2006-07-12 16:44:04 -0500 | [diff] [blame] | 159 | |
| 160 | DLM_ASSERT(lkb->lkb_astparam, dlm_print_lkb(lkb);); |
| 161 | ua = (struct dlm_user_args *)lkb->lkb_astparam; |
| 162 | proc = ua->proc; |
| 163 | |
| 164 | if (type == AST_BAST && ua->bastaddr == NULL) |
| 165 | goto out; |
| 166 | |
| 167 | spin_lock(&proc->asts_spin); |
David Teigland | ef0c2bb | 2007-03-28 09:56:46 -0500 | [diff] [blame] | 168 | |
| 169 | ast_type = lkb->lkb_ast_type; |
| 170 | lkb->lkb_ast_type |= type; |
| 171 | |
| 172 | if (!ast_type) { |
David Teigland | 597d0ca | 2006-07-12 16:44:04 -0500 | [diff] [blame] | 173 | kref_get(&lkb->lkb_ref); |
| 174 | list_add_tail(&lkb->lkb_astqueue, &proc->asts); |
David Teigland | 597d0ca | 2006-07-12 16:44:04 -0500 | [diff] [blame] | 175 | wake_up_interruptible(&proc->wait); |
| 176 | } |
David Teigland | ef0c2bb | 2007-03-28 09:56:46 -0500 | [diff] [blame] | 177 | if (type == AST_COMP && (ast_type & AST_COMP)) |
| 178 | log_debug(ls, "ast overlap %x status %x %x", |
| 179 | lkb->lkb_id, ua->lksb.sb_status, lkb->lkb_flags); |
David Teigland | 597d0ca | 2006-07-12 16:44:04 -0500 | [diff] [blame] | 180 | |
David Teigland | ef0c2bb | 2007-03-28 09:56:46 -0500 | [diff] [blame] | 181 | /* Figure out if this lock is at the end of its life and no longer |
| 182 | available for the application to use. The lkb still exists until |
| 183 | the final ast is read. A lock becomes EOL in three situations: |
| 184 | 1. a noqueue request fails with EAGAIN |
| 185 | 2. an unlock completes with EUNLOCK |
| 186 | 3. a cancel of a waiting request completes with ECANCEL |
| 187 | An EOL lock needs to be removed from the process's list of locks. |
| 188 | And we can't allow any new operation on an EOL lock. This is |
| 189 | not related to the lifetime of the lkb struct which is managed |
| 190 | entirely by refcount. */ |
David Teigland | 3609819 | 2006-07-20 08:35:39 -0500 | [diff] [blame] | 191 | |
David Teigland | ef0c2bb | 2007-03-28 09:56:46 -0500 | [diff] [blame] | 192 | if (type == AST_COMP && |
| 193 | lkb->lkb_grmode == DLM_LOCK_IV && |
| 194 | ua->lksb.sb_status == -EAGAIN) |
| 195 | eol = 1; |
| 196 | else if (ua->lksb.sb_status == -DLM_EUNLOCK || |
David Teigland | a1bc86e | 2007-01-15 10:34:52 -0600 | [diff] [blame] | 197 | (ua->lksb.sb_status == -DLM_ECANCEL && |
| 198 | lkb->lkb_grmode == DLM_LOCK_IV)) |
David Teigland | ef0c2bb | 2007-03-28 09:56:46 -0500 | [diff] [blame] | 199 | eol = 1; |
| 200 | if (eol) { |
| 201 | lkb->lkb_ast_type &= ~AST_BAST; |
| 202 | lkb->lkb_flags |= DLM_IFL_ENDOFLIFE; |
| 203 | } |
David Teigland | a1bc86e | 2007-01-15 10:34:52 -0600 | [diff] [blame] | 204 | |
David Teigland | 597d0ca | 2006-07-12 16:44:04 -0500 | [diff] [blame] | 205 | /* We want to copy the lvb to userspace when the completion |
| 206 | ast is read if the status is 0, the lock has an lvb and |
| 207 | lvb_ops says we should. We could probably have set_lvb_lock() |
| 208 | set update_user_lvb instead and not need old_mode */ |
| 209 | |
| 210 | if ((lkb->lkb_ast_type & AST_COMP) && |
| 211 | (lkb->lkb_lksb->sb_status == 0) && |
| 212 | lkb->lkb_lksb->sb_lvbptr && |
| 213 | dlm_lvb_operations[ua->old_mode + 1][lkb->lkb_grmode + 1]) |
| 214 | ua->update_user_lvb = 1; |
| 215 | else |
| 216 | ua->update_user_lvb = 0; |
| 217 | |
| 218 | spin_unlock(&proc->asts_spin); |
David Teigland | 34e22be | 2006-07-18 11:24:04 -0500 | [diff] [blame] | 219 | |
David Teigland | ef0c2bb | 2007-03-28 09:56:46 -0500 | [diff] [blame] | 220 | if (eol) { |
David Teigland | 34e22be | 2006-07-18 11:24:04 -0500 | [diff] [blame] | 221 | spin_lock(&ua->proc->locks_spin); |
David Teigland | ef0c2bb | 2007-03-28 09:56:46 -0500 | [diff] [blame] | 222 | if (!list_empty(&lkb->lkb_ownqueue)) { |
| 223 | list_del_init(&lkb->lkb_ownqueue); |
| 224 | dlm_put_lkb(lkb); |
| 225 | } |
David Teigland | 34e22be | 2006-07-18 11:24:04 -0500 | [diff] [blame] | 226 | spin_unlock(&ua->proc->locks_spin); |
David Teigland | 34e22be | 2006-07-18 11:24:04 -0500 | [diff] [blame] | 227 | } |
David Teigland | 597d0ca | 2006-07-12 16:44:04 -0500 | [diff] [blame] | 228 | out: |
| 229 | mutex_unlock(&ls->ls_clear_proc_locks); |
| 230 | } |
| 231 | |
| 232 | static int device_user_lock(struct dlm_user_proc *proc, |
| 233 | struct dlm_lock_params *params) |
| 234 | { |
| 235 | struct dlm_ls *ls; |
| 236 | struct dlm_user_args *ua; |
| 237 | int error = -ENOMEM; |
| 238 | |
| 239 | ls = dlm_find_lockspace_local(proc->lockspace); |
| 240 | if (!ls) |
| 241 | return -ENOENT; |
| 242 | |
| 243 | if (!params->castaddr || !params->lksb) { |
| 244 | error = -EINVAL; |
| 245 | goto out; |
| 246 | } |
| 247 | |
| 248 | ua = kzalloc(sizeof(struct dlm_user_args), GFP_KERNEL); |
| 249 | if (!ua) |
| 250 | goto out; |
| 251 | ua->proc = proc; |
| 252 | ua->user_lksb = params->lksb; |
| 253 | ua->castparam = params->castparam; |
| 254 | ua->castaddr = params->castaddr; |
| 255 | ua->bastparam = params->bastparam; |
| 256 | ua->bastaddr = params->bastaddr; |
| 257 | |
| 258 | if (params->flags & DLM_LKF_CONVERT) |
| 259 | error = dlm_user_convert(ls, ua, |
| 260 | params->mode, params->flags, |
| 261 | params->lkid, params->lvb); |
| 262 | else { |
| 263 | error = dlm_user_request(ls, ua, |
| 264 | params->mode, params->flags, |
| 265 | params->name, params->namelen, |
| 266 | params->parent); |
| 267 | if (!error) |
| 268 | error = ua->lksb.sb_lkid; |
| 269 | } |
| 270 | out: |
| 271 | dlm_put_lockspace(ls); |
| 272 | return error; |
| 273 | } |
| 274 | |
| 275 | static int device_user_unlock(struct dlm_user_proc *proc, |
| 276 | struct dlm_lock_params *params) |
| 277 | { |
| 278 | struct dlm_ls *ls; |
| 279 | struct dlm_user_args *ua; |
| 280 | int error = -ENOMEM; |
| 281 | |
| 282 | ls = dlm_find_lockspace_local(proc->lockspace); |
| 283 | if (!ls) |
| 284 | return -ENOENT; |
| 285 | |
| 286 | ua = kzalloc(sizeof(struct dlm_user_args), GFP_KERNEL); |
| 287 | if (!ua) |
| 288 | goto out; |
| 289 | ua->proc = proc; |
| 290 | ua->user_lksb = params->lksb; |
| 291 | ua->castparam = params->castparam; |
| 292 | ua->castaddr = params->castaddr; |
| 293 | |
| 294 | if (params->flags & DLM_LKF_CANCEL) |
| 295 | error = dlm_user_cancel(ls, ua, params->flags, params->lkid); |
| 296 | else |
| 297 | error = dlm_user_unlock(ls, ua, params->flags, params->lkid, |
| 298 | params->lvb); |
| 299 | out: |
| 300 | dlm_put_lockspace(ls); |
| 301 | return error; |
| 302 | } |
| 303 | |
Patrick Caulfield | 254da03 | 2007-03-21 09:23:53 +0000 | [diff] [blame] | 304 | static int create_misc_device(struct dlm_ls *ls, char *name) |
| 305 | { |
| 306 | int error, len; |
| 307 | |
| 308 | error = -ENOMEM; |
| 309 | len = strlen(name) + strlen(name_prefix) + 2; |
| 310 | ls->ls_device.name = kzalloc(len, GFP_KERNEL); |
| 311 | if (!ls->ls_device.name) |
| 312 | goto fail; |
| 313 | |
| 314 | snprintf((char *)ls->ls_device.name, len, "%s_%s", name_prefix, |
| 315 | name); |
| 316 | ls->ls_device.fops = &device_fops; |
| 317 | ls->ls_device.minor = MISC_DYNAMIC_MINOR; |
| 318 | |
| 319 | error = misc_register(&ls->ls_device); |
| 320 | if (error) { |
| 321 | kfree(ls->ls_device.name); |
| 322 | } |
| 323 | fail: |
| 324 | return error; |
| 325 | } |
| 326 | |
David Teigland | 72c2be7 | 2007-03-30 15:06:16 -0500 | [diff] [blame^] | 327 | static int device_user_purge(struct dlm_user_proc *proc, |
| 328 | struct dlm_purge_params *params) |
| 329 | { |
| 330 | struct dlm_ls *ls; |
| 331 | int error; |
| 332 | |
| 333 | ls = dlm_find_lockspace_local(proc->lockspace); |
| 334 | if (!ls) |
| 335 | return -ENOENT; |
| 336 | |
| 337 | error = dlm_user_purge(ls, proc, params->nodeid, params->pid); |
| 338 | |
| 339 | dlm_put_lockspace(ls); |
| 340 | return error; |
| 341 | } |
| 342 | |
David Teigland | 597d0ca | 2006-07-12 16:44:04 -0500 | [diff] [blame] | 343 | static int device_create_lockspace(struct dlm_lspace_params *params) |
| 344 | { |
| 345 | dlm_lockspace_t *lockspace; |
| 346 | struct dlm_ls *ls; |
Patrick Caulfield | 254da03 | 2007-03-21 09:23:53 +0000 | [diff] [blame] | 347 | int error; |
David Teigland | 597d0ca | 2006-07-12 16:44:04 -0500 | [diff] [blame] | 348 | |
| 349 | if (!capable(CAP_SYS_ADMIN)) |
| 350 | return -EPERM; |
| 351 | |
| 352 | error = dlm_new_lockspace(params->name, strlen(params->name), |
| 353 | &lockspace, 0, DLM_USER_LVB_LEN); |
| 354 | if (error) |
| 355 | return error; |
| 356 | |
| 357 | ls = dlm_find_lockspace_local(lockspace); |
| 358 | if (!ls) |
| 359 | return -ENOENT; |
| 360 | |
Patrick Caulfield | 254da03 | 2007-03-21 09:23:53 +0000 | [diff] [blame] | 361 | error = create_misc_device(ls, params->name); |
David Teigland | 597d0ca | 2006-07-12 16:44:04 -0500 | [diff] [blame] | 362 | dlm_put_lockspace(ls); |
David Teigland | 597d0ca | 2006-07-12 16:44:04 -0500 | [diff] [blame] | 363 | |
Patrick Caulfield | 254da03 | 2007-03-21 09:23:53 +0000 | [diff] [blame] | 364 | if (error) |
| 365 | dlm_release_lockspace(lockspace, 0); |
| 366 | else |
| 367 | error = ls->ls_device.minor; |
| 368 | |
David Teigland | 597d0ca | 2006-07-12 16:44:04 -0500 | [diff] [blame] | 369 | return error; |
| 370 | } |
| 371 | |
| 372 | static int device_remove_lockspace(struct dlm_lspace_params *params) |
| 373 | { |
| 374 | dlm_lockspace_t *lockspace; |
| 375 | struct dlm_ls *ls; |
David Teigland | c6e6f0b | 2006-08-30 10:50:18 -0500 | [diff] [blame] | 376 | int error, force = 0; |
David Teigland | 597d0ca | 2006-07-12 16:44:04 -0500 | [diff] [blame] | 377 | |
| 378 | if (!capable(CAP_SYS_ADMIN)) |
| 379 | return -EPERM; |
| 380 | |
| 381 | ls = dlm_find_lockspace_device(params->minor); |
| 382 | if (!ls) |
| 383 | return -ENOENT; |
| 384 | |
Patrick Caulfield | 254da03 | 2007-03-21 09:23:53 +0000 | [diff] [blame] | 385 | /* Deregister the misc device first, so we don't have |
| 386 | * a device that's not attached to a lockspace. If |
| 387 | * dlm_release_lockspace fails then we can recreate it |
| 388 | */ |
David Teigland | 597d0ca | 2006-07-12 16:44:04 -0500 | [diff] [blame] | 389 | error = misc_deregister(&ls->ls_device); |
| 390 | if (error) { |
| 391 | dlm_put_lockspace(ls); |
| 392 | goto out; |
| 393 | } |
| 394 | kfree(ls->ls_device.name); |
| 395 | |
David Teigland | c6e6f0b | 2006-08-30 10:50:18 -0500 | [diff] [blame] | 396 | if (params->flags & DLM_USER_LSFLG_FORCEFREE) |
| 397 | force = 2; |
| 398 | |
David Teigland | 597d0ca | 2006-07-12 16:44:04 -0500 | [diff] [blame] | 399 | lockspace = ls->ls_local_handle; |
| 400 | |
| 401 | /* dlm_release_lockspace waits for references to go to zero, |
| 402 | so all processes will need to close their device for the ls |
| 403 | before the release will procede */ |
| 404 | |
| 405 | dlm_put_lockspace(ls); |
David Teigland | c6e6f0b | 2006-08-30 10:50:18 -0500 | [diff] [blame] | 406 | error = dlm_release_lockspace(lockspace, force); |
Patrick Caulfield | 254da03 | 2007-03-21 09:23:53 +0000 | [diff] [blame] | 407 | if (error) |
| 408 | create_misc_device(ls, ls->ls_name); |
David Teigland | c6e6f0b | 2006-08-30 10:50:18 -0500 | [diff] [blame] | 409 | out: |
David Teigland | 597d0ca | 2006-07-12 16:44:04 -0500 | [diff] [blame] | 410 | return error; |
| 411 | } |
| 412 | |
| 413 | /* Check the user's version matches ours */ |
| 414 | static int check_version(struct dlm_write_request *req) |
| 415 | { |
| 416 | if (req->version[0] != DLM_DEVICE_VERSION_MAJOR || |
| 417 | (req->version[0] == DLM_DEVICE_VERSION_MAJOR && |
| 418 | req->version[1] > DLM_DEVICE_VERSION_MINOR)) { |
| 419 | |
| 420 | printk(KERN_DEBUG "dlm: process %s (%d) version mismatch " |
| 421 | "user (%d.%d.%d) kernel (%d.%d.%d)\n", |
| 422 | current->comm, |
| 423 | current->pid, |
| 424 | req->version[0], |
| 425 | req->version[1], |
| 426 | req->version[2], |
| 427 | DLM_DEVICE_VERSION_MAJOR, |
| 428 | DLM_DEVICE_VERSION_MINOR, |
| 429 | DLM_DEVICE_VERSION_PATCH); |
| 430 | return -EINVAL; |
| 431 | } |
| 432 | return 0; |
| 433 | } |
| 434 | |
| 435 | /* |
| 436 | * device_write |
| 437 | * |
| 438 | * device_user_lock |
| 439 | * dlm_user_request -> request_lock |
| 440 | * dlm_user_convert -> convert_lock |
| 441 | * |
| 442 | * device_user_unlock |
| 443 | * dlm_user_unlock -> unlock_lock |
| 444 | * dlm_user_cancel -> cancel_lock |
| 445 | * |
| 446 | * device_create_lockspace |
| 447 | * dlm_new_lockspace |
| 448 | * |
| 449 | * device_remove_lockspace |
| 450 | * dlm_release_lockspace |
| 451 | */ |
| 452 | |
| 453 | /* a write to a lockspace device is a lock or unlock request, a write |
| 454 | to the control device is to create/remove a lockspace */ |
| 455 | |
| 456 | static ssize_t device_write(struct file *file, const char __user *buf, |
| 457 | size_t count, loff_t *ppos) |
| 458 | { |
| 459 | struct dlm_user_proc *proc = file->private_data; |
| 460 | struct dlm_write_request *kbuf; |
| 461 | sigset_t tmpsig, allsigs; |
| 462 | int error; |
| 463 | |
| 464 | #ifdef CONFIG_COMPAT |
| 465 | if (count < sizeof(struct dlm_write_request32)) |
| 466 | #else |
| 467 | if (count < sizeof(struct dlm_write_request)) |
| 468 | #endif |
| 469 | return -EINVAL; |
| 470 | |
| 471 | kbuf = kmalloc(count, GFP_KERNEL); |
| 472 | if (!kbuf) |
| 473 | return -ENOMEM; |
| 474 | |
| 475 | if (copy_from_user(kbuf, buf, count)) { |
| 476 | error = -EFAULT; |
| 477 | goto out_free; |
| 478 | } |
| 479 | |
| 480 | if (check_version(kbuf)) { |
| 481 | error = -EBADE; |
| 482 | goto out_free; |
| 483 | } |
| 484 | |
| 485 | #ifdef CONFIG_COMPAT |
| 486 | if (!kbuf->is64bit) { |
| 487 | struct dlm_write_request32 *k32buf; |
| 488 | k32buf = (struct dlm_write_request32 *)kbuf; |
| 489 | kbuf = kmalloc(count + (sizeof(struct dlm_write_request) - |
| 490 | sizeof(struct dlm_write_request32)), GFP_KERNEL); |
| 491 | if (!kbuf) |
| 492 | return -ENOMEM; |
| 493 | |
| 494 | if (proc) |
| 495 | set_bit(DLM_PROC_FLAGS_COMPAT, &proc->flags); |
| 496 | compat_input(kbuf, k32buf); |
| 497 | kfree(k32buf); |
| 498 | } |
| 499 | #endif |
| 500 | |
| 501 | /* do we really need this? can a write happen after a close? */ |
| 502 | if ((kbuf->cmd == DLM_USER_LOCK || kbuf->cmd == DLM_USER_UNLOCK) && |
| 503 | test_bit(DLM_PROC_FLAGS_CLOSING, &proc->flags)) |
| 504 | return -EINVAL; |
| 505 | |
| 506 | sigfillset(&allsigs); |
| 507 | sigprocmask(SIG_BLOCK, &allsigs, &tmpsig); |
| 508 | |
| 509 | error = -EINVAL; |
| 510 | |
| 511 | switch (kbuf->cmd) |
| 512 | { |
| 513 | case DLM_USER_LOCK: |
| 514 | if (!proc) { |
| 515 | log_print("no locking on control device"); |
| 516 | goto out_sig; |
| 517 | } |
| 518 | error = device_user_lock(proc, &kbuf->i.lock); |
| 519 | break; |
| 520 | |
| 521 | case DLM_USER_UNLOCK: |
| 522 | if (!proc) { |
| 523 | log_print("no locking on control device"); |
| 524 | goto out_sig; |
| 525 | } |
| 526 | error = device_user_unlock(proc, &kbuf->i.lock); |
| 527 | break; |
| 528 | |
| 529 | case DLM_USER_CREATE_LOCKSPACE: |
| 530 | if (proc) { |
| 531 | log_print("create/remove only on control device"); |
| 532 | goto out_sig; |
| 533 | } |
| 534 | error = device_create_lockspace(&kbuf->i.lspace); |
| 535 | break; |
| 536 | |
| 537 | case DLM_USER_REMOVE_LOCKSPACE: |
| 538 | if (proc) { |
| 539 | log_print("create/remove only on control device"); |
| 540 | goto out_sig; |
| 541 | } |
| 542 | error = device_remove_lockspace(&kbuf->i.lspace); |
| 543 | break; |
| 544 | |
David Teigland | 72c2be7 | 2007-03-30 15:06:16 -0500 | [diff] [blame^] | 545 | case DLM_USER_PURGE: |
| 546 | if (!proc) { |
| 547 | log_print("no locking on control device"); |
| 548 | goto out_sig; |
| 549 | } |
| 550 | error = device_user_purge(proc, &kbuf->i.purge); |
| 551 | break; |
| 552 | |
David Teigland | 597d0ca | 2006-07-12 16:44:04 -0500 | [diff] [blame] | 553 | default: |
| 554 | log_print("Unknown command passed to DLM device : %d\n", |
| 555 | kbuf->cmd); |
| 556 | } |
| 557 | |
| 558 | out_sig: |
| 559 | sigprocmask(SIG_SETMASK, &tmpsig, NULL); |
| 560 | recalc_sigpending(); |
| 561 | out_free: |
| 562 | kfree(kbuf); |
| 563 | return error; |
| 564 | } |
| 565 | |
| 566 | /* Every process that opens the lockspace device has its own "proc" structure |
| 567 | hanging off the open file that's used to keep track of locks owned by the |
| 568 | process and asts that need to be delivered to the process. */ |
| 569 | |
| 570 | static int device_open(struct inode *inode, struct file *file) |
| 571 | { |
| 572 | struct dlm_user_proc *proc; |
| 573 | struct dlm_ls *ls; |
| 574 | |
| 575 | ls = dlm_find_lockspace_device(iminor(inode)); |
| 576 | if (!ls) |
| 577 | return -ENOENT; |
| 578 | |
| 579 | proc = kzalloc(sizeof(struct dlm_user_proc), GFP_KERNEL); |
| 580 | if (!proc) { |
| 581 | dlm_put_lockspace(ls); |
| 582 | return -ENOMEM; |
| 583 | } |
| 584 | |
| 585 | proc->lockspace = ls->ls_local_handle; |
| 586 | INIT_LIST_HEAD(&proc->asts); |
| 587 | INIT_LIST_HEAD(&proc->locks); |
David Teigland | a1bc86e | 2007-01-15 10:34:52 -0600 | [diff] [blame] | 588 | INIT_LIST_HEAD(&proc->unlocking); |
David Teigland | 597d0ca | 2006-07-12 16:44:04 -0500 | [diff] [blame] | 589 | spin_lock_init(&proc->asts_spin); |
| 590 | spin_lock_init(&proc->locks_spin); |
| 591 | init_waitqueue_head(&proc->wait); |
| 592 | file->private_data = proc; |
| 593 | |
| 594 | return 0; |
| 595 | } |
| 596 | |
| 597 | static int device_close(struct inode *inode, struct file *file) |
| 598 | { |
| 599 | struct dlm_user_proc *proc = file->private_data; |
| 600 | struct dlm_ls *ls; |
| 601 | sigset_t tmpsig, allsigs; |
| 602 | |
| 603 | ls = dlm_find_lockspace_local(proc->lockspace); |
| 604 | if (!ls) |
| 605 | return -ENOENT; |
| 606 | |
| 607 | sigfillset(&allsigs); |
| 608 | sigprocmask(SIG_BLOCK, &allsigs, &tmpsig); |
| 609 | |
| 610 | set_bit(DLM_PROC_FLAGS_CLOSING, &proc->flags); |
| 611 | |
| 612 | dlm_clear_proc_locks(ls, proc); |
| 613 | |
| 614 | /* at this point no more lkb's should exist for this lockspace, |
| 615 | so there's no chance of dlm_user_add_ast() being called and |
| 616 | looking for lkb->ua->proc */ |
| 617 | |
| 618 | kfree(proc); |
| 619 | file->private_data = NULL; |
| 620 | |
| 621 | dlm_put_lockspace(ls); |
| 622 | dlm_put_lockspace(ls); /* for the find in device_open() */ |
| 623 | |
| 624 | /* FIXME: AUTOFREE: if this ls is no longer used do |
| 625 | device_remove_lockspace() */ |
| 626 | |
| 627 | sigprocmask(SIG_SETMASK, &tmpsig, NULL); |
| 628 | recalc_sigpending(); |
| 629 | |
| 630 | return 0; |
| 631 | } |
| 632 | |
| 633 | static int copy_result_to_user(struct dlm_user_args *ua, int compat, int type, |
| 634 | int bmode, char __user *buf, size_t count) |
| 635 | { |
| 636 | #ifdef CONFIG_COMPAT |
| 637 | struct dlm_lock_result32 result32; |
| 638 | #endif |
| 639 | struct dlm_lock_result result; |
| 640 | void *resultptr; |
| 641 | int error=0; |
| 642 | int len; |
| 643 | int struct_len; |
| 644 | |
| 645 | memset(&result, 0, sizeof(struct dlm_lock_result)); |
| 646 | memcpy(&result.lksb, &ua->lksb, sizeof(struct dlm_lksb)); |
| 647 | result.user_lksb = ua->user_lksb; |
| 648 | |
| 649 | /* FIXME: dlm1 provides for the user's bastparam/addr to not be updated |
| 650 | in a conversion unless the conversion is successful. See code |
| 651 | in dlm_user_convert() for updating ua from ua_tmp. OpenVMS, though, |
| 652 | notes that a new blocking AST address and parameter are set even if |
| 653 | the conversion fails, so maybe we should just do that. */ |
| 654 | |
| 655 | if (type == AST_BAST) { |
| 656 | result.user_astaddr = ua->bastaddr; |
| 657 | result.user_astparam = ua->bastparam; |
| 658 | result.bast_mode = bmode; |
| 659 | } else { |
| 660 | result.user_astaddr = ua->castaddr; |
| 661 | result.user_astparam = ua->castparam; |
| 662 | } |
| 663 | |
| 664 | #ifdef CONFIG_COMPAT |
| 665 | if (compat) |
| 666 | len = sizeof(struct dlm_lock_result32); |
| 667 | else |
| 668 | #endif |
| 669 | len = sizeof(struct dlm_lock_result); |
| 670 | struct_len = len; |
| 671 | |
| 672 | /* copy lvb to userspace if there is one, it's been updated, and |
| 673 | the user buffer has space for it */ |
| 674 | |
| 675 | if (ua->update_user_lvb && ua->lksb.sb_lvbptr && |
| 676 | count >= len + DLM_USER_LVB_LEN) { |
| 677 | if (copy_to_user(buf+len, ua->lksb.sb_lvbptr, |
| 678 | DLM_USER_LVB_LEN)) { |
| 679 | error = -EFAULT; |
| 680 | goto out; |
| 681 | } |
| 682 | |
| 683 | result.lvb_offset = len; |
| 684 | len += DLM_USER_LVB_LEN; |
| 685 | } |
| 686 | |
| 687 | result.length = len; |
| 688 | resultptr = &result; |
| 689 | #ifdef CONFIG_COMPAT |
| 690 | if (compat) { |
| 691 | compat_output(&result, &result32); |
| 692 | resultptr = &result32; |
| 693 | } |
| 694 | #endif |
| 695 | |
| 696 | if (copy_to_user(buf, resultptr, struct_len)) |
| 697 | error = -EFAULT; |
| 698 | else |
| 699 | error = len; |
| 700 | out: |
| 701 | return error; |
| 702 | } |
| 703 | |
| 704 | /* a read returns a single ast described in a struct dlm_lock_result */ |
| 705 | |
| 706 | static ssize_t device_read(struct file *file, char __user *buf, size_t count, |
| 707 | loff_t *ppos) |
| 708 | { |
| 709 | struct dlm_user_proc *proc = file->private_data; |
| 710 | struct dlm_lkb *lkb; |
| 711 | struct dlm_user_args *ua; |
| 712 | DECLARE_WAITQUEUE(wait, current); |
| 713 | int error, type=0, bmode=0, removed = 0; |
| 714 | |
| 715 | #ifdef CONFIG_COMPAT |
| 716 | if (count < sizeof(struct dlm_lock_result32)) |
| 717 | #else |
| 718 | if (count < sizeof(struct dlm_lock_result)) |
| 719 | #endif |
| 720 | return -EINVAL; |
| 721 | |
| 722 | /* do we really need this? can a read happen after a close? */ |
| 723 | if (test_bit(DLM_PROC_FLAGS_CLOSING, &proc->flags)) |
| 724 | return -EINVAL; |
| 725 | |
| 726 | spin_lock(&proc->asts_spin); |
| 727 | if (list_empty(&proc->asts)) { |
| 728 | if (file->f_flags & O_NONBLOCK) { |
| 729 | spin_unlock(&proc->asts_spin); |
| 730 | return -EAGAIN; |
| 731 | } |
| 732 | |
| 733 | add_wait_queue(&proc->wait, &wait); |
| 734 | |
| 735 | repeat: |
| 736 | set_current_state(TASK_INTERRUPTIBLE); |
| 737 | if (list_empty(&proc->asts) && !signal_pending(current)) { |
| 738 | spin_unlock(&proc->asts_spin); |
| 739 | schedule(); |
| 740 | spin_lock(&proc->asts_spin); |
| 741 | goto repeat; |
| 742 | } |
| 743 | set_current_state(TASK_RUNNING); |
| 744 | remove_wait_queue(&proc->wait, &wait); |
| 745 | |
| 746 | if (signal_pending(current)) { |
| 747 | spin_unlock(&proc->asts_spin); |
| 748 | return -ERESTARTSYS; |
| 749 | } |
| 750 | } |
| 751 | |
| 752 | if (list_empty(&proc->asts)) { |
| 753 | spin_unlock(&proc->asts_spin); |
| 754 | return -EAGAIN; |
| 755 | } |
| 756 | |
| 757 | /* there may be both completion and blocking asts to return for |
| 758 | the lkb, don't remove lkb from asts list unless no asts remain */ |
| 759 | |
| 760 | lkb = list_entry(proc->asts.next, struct dlm_lkb, lkb_astqueue); |
| 761 | |
| 762 | if (lkb->lkb_ast_type & AST_COMP) { |
| 763 | lkb->lkb_ast_type &= ~AST_COMP; |
| 764 | type = AST_COMP; |
| 765 | } else if (lkb->lkb_ast_type & AST_BAST) { |
| 766 | lkb->lkb_ast_type &= ~AST_BAST; |
| 767 | type = AST_BAST; |
| 768 | bmode = lkb->lkb_bastmode; |
| 769 | } |
| 770 | |
| 771 | if (!lkb->lkb_ast_type) { |
| 772 | list_del(&lkb->lkb_astqueue); |
| 773 | removed = 1; |
| 774 | } |
| 775 | spin_unlock(&proc->asts_spin); |
| 776 | |
| 777 | ua = (struct dlm_user_args *)lkb->lkb_astparam; |
| 778 | error = copy_result_to_user(ua, |
| 779 | test_bit(DLM_PROC_FLAGS_COMPAT, &proc->flags), |
| 780 | type, bmode, buf, count); |
| 781 | |
| 782 | /* removes reference for the proc->asts lists added by |
| 783 | dlm_user_add_ast() and may result in the lkb being freed */ |
| 784 | if (removed) |
| 785 | dlm_put_lkb(lkb); |
| 786 | |
| 787 | return error; |
| 788 | } |
| 789 | |
| 790 | static unsigned int device_poll(struct file *file, poll_table *wait) |
| 791 | { |
| 792 | struct dlm_user_proc *proc = file->private_data; |
| 793 | |
| 794 | poll_wait(file, &proc->wait, wait); |
| 795 | |
| 796 | spin_lock(&proc->asts_spin); |
| 797 | if (!list_empty(&proc->asts)) { |
| 798 | spin_unlock(&proc->asts_spin); |
| 799 | return POLLIN | POLLRDNORM; |
| 800 | } |
| 801 | spin_unlock(&proc->asts_spin); |
| 802 | return 0; |
| 803 | } |
| 804 | |
| 805 | static int ctl_device_open(struct inode *inode, struct file *file) |
| 806 | { |
| 807 | file->private_data = NULL; |
| 808 | return 0; |
| 809 | } |
| 810 | |
| 811 | static int ctl_device_close(struct inode *inode, struct file *file) |
| 812 | { |
| 813 | return 0; |
| 814 | } |
| 815 | |
Arjan van de Ven | 00977a5 | 2007-02-12 00:55:34 -0800 | [diff] [blame] | 816 | static const struct file_operations device_fops = { |
David Teigland | 597d0ca | 2006-07-12 16:44:04 -0500 | [diff] [blame] | 817 | .open = device_open, |
| 818 | .release = device_close, |
| 819 | .read = device_read, |
| 820 | .write = device_write, |
| 821 | .poll = device_poll, |
| 822 | .owner = THIS_MODULE, |
| 823 | }; |
| 824 | |
Arjan van de Ven | 00977a5 | 2007-02-12 00:55:34 -0800 | [diff] [blame] | 825 | static const struct file_operations ctl_device_fops = { |
David Teigland | 597d0ca | 2006-07-12 16:44:04 -0500 | [diff] [blame] | 826 | .open = ctl_device_open, |
| 827 | .release = ctl_device_close, |
| 828 | .write = device_write, |
| 829 | .owner = THIS_MODULE, |
| 830 | }; |
| 831 | |
| 832 | int dlm_user_init(void) |
| 833 | { |
| 834 | int error; |
| 835 | |
| 836 | ctl_device.name = "dlm-control"; |
| 837 | ctl_device.fops = &ctl_device_fops; |
| 838 | ctl_device.minor = MISC_DYNAMIC_MINOR; |
| 839 | |
| 840 | error = misc_register(&ctl_device); |
| 841 | if (error) |
| 842 | log_print("misc_register failed for control device"); |
| 843 | |
| 844 | return error; |
| 845 | } |
| 846 | |
| 847 | void dlm_user_exit(void) |
| 848 | { |
| 849 | misc_deregister(&ctl_device); |
| 850 | } |
| 851 | |