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1012 lines
24 KiB
1012 lines
24 KiB
// SPDX-License-Identifier: GPL-2.0-only |
|
/* |
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* Copyright (C) 2006-2010 Red Hat, Inc. All rights reserved. |
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*/ |
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|
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#include <linux/miscdevice.h> |
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#include <linux/init.h> |
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#include <linux/wait.h> |
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#include <linux/file.h> |
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#include <linux/fs.h> |
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#include <linux/poll.h> |
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#include <linux/signal.h> |
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#include <linux/spinlock.h> |
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#include <linux/dlm.h> |
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#include <linux/dlm_device.h> |
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#include <linux/slab.h> |
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#include <linux/sched/signal.h> |
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|
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#include "dlm_internal.h" |
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#include "lockspace.h" |
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#include "lock.h" |
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#include "lvb_table.h" |
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#include "user.h" |
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#include "ast.h" |
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#include "config.h" |
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|
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static const char name_prefix[] = "dlm"; |
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static const struct file_operations device_fops; |
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static atomic_t dlm_monitor_opened; |
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static int dlm_monitor_unused = 1; |
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|
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#ifdef CONFIG_COMPAT |
|
|
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struct dlm_lock_params32 { |
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__u8 mode; |
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__u8 namelen; |
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__u16 unused; |
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__u32 flags; |
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__u32 lkid; |
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__u32 parent; |
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__u64 xid; |
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__u64 timeout; |
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__u32 castparam; |
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__u32 castaddr; |
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__u32 bastparam; |
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__u32 bastaddr; |
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__u32 lksb; |
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char lvb[DLM_USER_LVB_LEN]; |
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char name[]; |
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}; |
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|
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struct dlm_write_request32 { |
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__u32 version[3]; |
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__u8 cmd; |
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__u8 is64bit; |
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__u8 unused[2]; |
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|
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union { |
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struct dlm_lock_params32 lock; |
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struct dlm_lspace_params lspace; |
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struct dlm_purge_params purge; |
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} i; |
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}; |
|
|
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struct dlm_lksb32 { |
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__u32 sb_status; |
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__u32 sb_lkid; |
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__u8 sb_flags; |
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__u32 sb_lvbptr; |
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}; |
|
|
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struct dlm_lock_result32 { |
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__u32 version[3]; |
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__u32 length; |
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__u32 user_astaddr; |
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__u32 user_astparam; |
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__u32 user_lksb; |
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struct dlm_lksb32 lksb; |
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__u8 bast_mode; |
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__u8 unused[3]; |
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/* Offsets may be zero if no data is present */ |
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__u32 lvb_offset; |
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}; |
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|
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static void compat_input(struct dlm_write_request *kb, |
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struct dlm_write_request32 *kb32, |
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int namelen) |
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{ |
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kb->version[0] = kb32->version[0]; |
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kb->version[1] = kb32->version[1]; |
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kb->version[2] = kb32->version[2]; |
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|
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kb->cmd = kb32->cmd; |
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kb->is64bit = kb32->is64bit; |
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if (kb->cmd == DLM_USER_CREATE_LOCKSPACE || |
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kb->cmd == DLM_USER_REMOVE_LOCKSPACE) { |
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kb->i.lspace.flags = kb32->i.lspace.flags; |
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kb->i.lspace.minor = kb32->i.lspace.minor; |
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memcpy(kb->i.lspace.name, kb32->i.lspace.name, namelen); |
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} else if (kb->cmd == DLM_USER_PURGE) { |
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kb->i.purge.nodeid = kb32->i.purge.nodeid; |
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kb->i.purge.pid = kb32->i.purge.pid; |
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} else { |
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kb->i.lock.mode = kb32->i.lock.mode; |
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kb->i.lock.namelen = kb32->i.lock.namelen; |
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kb->i.lock.flags = kb32->i.lock.flags; |
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kb->i.lock.lkid = kb32->i.lock.lkid; |
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kb->i.lock.parent = kb32->i.lock.parent; |
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kb->i.lock.xid = kb32->i.lock.xid; |
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kb->i.lock.timeout = kb32->i.lock.timeout; |
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kb->i.lock.castparam = (void *)(long)kb32->i.lock.castparam; |
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kb->i.lock.castaddr = (void *)(long)kb32->i.lock.castaddr; |
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kb->i.lock.bastparam = (void *)(long)kb32->i.lock.bastparam; |
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kb->i.lock.bastaddr = (void *)(long)kb32->i.lock.bastaddr; |
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kb->i.lock.lksb = (void *)(long)kb32->i.lock.lksb; |
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memcpy(kb->i.lock.lvb, kb32->i.lock.lvb, DLM_USER_LVB_LEN); |
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memcpy(kb->i.lock.name, kb32->i.lock.name, namelen); |
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} |
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} |
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|
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static void compat_output(struct dlm_lock_result *res, |
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struct dlm_lock_result32 *res32) |
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{ |
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memset(res32, 0, sizeof(*res32)); |
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|
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res32->version[0] = res->version[0]; |
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res32->version[1] = res->version[1]; |
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res32->version[2] = res->version[2]; |
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|
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res32->user_astaddr = (__u32)(long)res->user_astaddr; |
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res32->user_astparam = (__u32)(long)res->user_astparam; |
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res32->user_lksb = (__u32)(long)res->user_lksb; |
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res32->bast_mode = res->bast_mode; |
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|
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res32->lvb_offset = res->lvb_offset; |
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res32->length = res->length; |
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|
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res32->lksb.sb_status = res->lksb.sb_status; |
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res32->lksb.sb_flags = res->lksb.sb_flags; |
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res32->lksb.sb_lkid = res->lksb.sb_lkid; |
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res32->lksb.sb_lvbptr = (__u32)(long)res->lksb.sb_lvbptr; |
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} |
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#endif |
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|
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/* Figure out if this lock is at the end of its life and no longer |
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available for the application to use. The lkb still exists until |
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the final ast is read. A lock becomes EOL in three situations: |
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1. a noqueue request fails with EAGAIN |
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2. an unlock completes with EUNLOCK |
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3. a cancel of a waiting request completes with ECANCEL/EDEADLK |
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An EOL lock needs to be removed from the process's list of locks. |
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And we can't allow any new operation on an EOL lock. This is |
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not related to the lifetime of the lkb struct which is managed |
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entirely by refcount. */ |
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|
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static int lkb_is_endoflife(int mode, int status) |
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{ |
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switch (status) { |
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case -DLM_EUNLOCK: |
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return 1; |
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case -DLM_ECANCEL: |
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case -ETIMEDOUT: |
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case -EDEADLK: |
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case -EAGAIN: |
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if (mode == DLM_LOCK_IV) |
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return 1; |
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break; |
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} |
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return 0; |
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} |
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|
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/* we could possibly check if the cancel of an orphan has resulted in the lkb |
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being removed and then remove that lkb from the orphans list and free it */ |
|
|
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void dlm_user_add_ast(struct dlm_lkb *lkb, uint32_t flags, int mode, |
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int status, uint32_t sbflags, uint64_t seq) |
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{ |
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struct dlm_ls *ls; |
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struct dlm_user_args *ua; |
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struct dlm_user_proc *proc; |
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int rv; |
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|
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if (lkb->lkb_flags & (DLM_IFL_ORPHAN | DLM_IFL_DEAD)) |
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return; |
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|
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ls = lkb->lkb_resource->res_ls; |
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mutex_lock(&ls->ls_clear_proc_locks); |
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|
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/* If ORPHAN/DEAD flag is set, it means the process is dead so an ast |
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can't be delivered. For ORPHAN's, dlm_clear_proc_locks() freed |
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lkb->ua so we can't try to use it. This second check is necessary |
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for cases where a completion ast is received for an operation that |
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began before clear_proc_locks did its cancel/unlock. */ |
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|
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if (lkb->lkb_flags & (DLM_IFL_ORPHAN | DLM_IFL_DEAD)) |
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goto out; |
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|
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DLM_ASSERT(lkb->lkb_ua, dlm_print_lkb(lkb);); |
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ua = lkb->lkb_ua; |
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proc = ua->proc; |
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|
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if ((flags & DLM_CB_BAST) && ua->bastaddr == NULL) |
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goto out; |
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|
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if ((flags & DLM_CB_CAST) && lkb_is_endoflife(mode, status)) |
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lkb->lkb_flags |= DLM_IFL_ENDOFLIFE; |
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|
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spin_lock(&proc->asts_spin); |
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|
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rv = dlm_add_lkb_callback(lkb, flags, mode, status, sbflags, seq); |
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if (rv < 0) { |
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spin_unlock(&proc->asts_spin); |
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goto out; |
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} |
|
|
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if (list_empty(&lkb->lkb_cb_list)) { |
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kref_get(&lkb->lkb_ref); |
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list_add_tail(&lkb->lkb_cb_list, &proc->asts); |
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wake_up_interruptible(&proc->wait); |
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} |
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spin_unlock(&proc->asts_spin); |
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|
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if (lkb->lkb_flags & DLM_IFL_ENDOFLIFE) { |
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/* N.B. spin_lock locks_spin, not asts_spin */ |
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spin_lock(&proc->locks_spin); |
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if (!list_empty(&lkb->lkb_ownqueue)) { |
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list_del_init(&lkb->lkb_ownqueue); |
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dlm_put_lkb(lkb); |
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} |
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spin_unlock(&proc->locks_spin); |
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} |
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out: |
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mutex_unlock(&ls->ls_clear_proc_locks); |
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} |
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|
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static int device_user_lock(struct dlm_user_proc *proc, |
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struct dlm_lock_params *params) |
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{ |
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struct dlm_ls *ls; |
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struct dlm_user_args *ua; |
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uint32_t lkid; |
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int error = -ENOMEM; |
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|
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ls = dlm_find_lockspace_local(proc->lockspace); |
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if (!ls) |
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return -ENOENT; |
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|
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if (!params->castaddr || !params->lksb) { |
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error = -EINVAL; |
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goto out; |
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} |
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ua = kzalloc(sizeof(struct dlm_user_args), GFP_NOFS); |
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if (!ua) |
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goto out; |
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ua->proc = proc; |
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ua->user_lksb = params->lksb; |
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ua->castparam = params->castparam; |
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ua->castaddr = params->castaddr; |
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ua->bastparam = params->bastparam; |
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ua->bastaddr = params->bastaddr; |
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ua->xid = params->xid; |
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|
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if (params->flags & DLM_LKF_CONVERT) { |
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error = dlm_user_convert(ls, ua, |
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params->mode, params->flags, |
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params->lkid, params->lvb, |
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(unsigned long) params->timeout); |
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} else if (params->flags & DLM_LKF_ORPHAN) { |
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error = dlm_user_adopt_orphan(ls, ua, |
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params->mode, params->flags, |
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params->name, params->namelen, |
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(unsigned long) params->timeout, |
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&lkid); |
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if (!error) |
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error = lkid; |
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} else { |
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error = dlm_user_request(ls, ua, |
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params->mode, params->flags, |
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params->name, params->namelen, |
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(unsigned long) params->timeout); |
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if (!error) |
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error = ua->lksb.sb_lkid; |
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} |
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out: |
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dlm_put_lockspace(ls); |
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return error; |
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} |
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|
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static int device_user_unlock(struct dlm_user_proc *proc, |
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struct dlm_lock_params *params) |
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{ |
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struct dlm_ls *ls; |
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struct dlm_user_args *ua; |
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int error = -ENOMEM; |
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|
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ls = dlm_find_lockspace_local(proc->lockspace); |
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if (!ls) |
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return -ENOENT; |
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|
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ua = kzalloc(sizeof(struct dlm_user_args), GFP_NOFS); |
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if (!ua) |
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goto out; |
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ua->proc = proc; |
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ua->user_lksb = params->lksb; |
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ua->castparam = params->castparam; |
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ua->castaddr = params->castaddr; |
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|
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if (params->flags & DLM_LKF_CANCEL) |
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error = dlm_user_cancel(ls, ua, params->flags, params->lkid); |
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else |
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error = dlm_user_unlock(ls, ua, params->flags, params->lkid, |
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params->lvb); |
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out: |
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dlm_put_lockspace(ls); |
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return error; |
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} |
|
|
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static int device_user_deadlock(struct dlm_user_proc *proc, |
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struct dlm_lock_params *params) |
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{ |
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struct dlm_ls *ls; |
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int error; |
|
|
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ls = dlm_find_lockspace_local(proc->lockspace); |
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if (!ls) |
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return -ENOENT; |
|
|
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error = dlm_user_deadlock(ls, params->flags, params->lkid); |
|
|
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dlm_put_lockspace(ls); |
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return error; |
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} |
|
|
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static int dlm_device_register(struct dlm_ls *ls, char *name) |
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{ |
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int error, len; |
|
|
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/* The device is already registered. This happens when the |
|
lockspace is created multiple times from userspace. */ |
|
if (ls->ls_device.name) |
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return 0; |
|
|
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error = -ENOMEM; |
|
len = strlen(name) + strlen(name_prefix) + 2; |
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ls->ls_device.name = kzalloc(len, GFP_NOFS); |
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if (!ls->ls_device.name) |
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goto fail; |
|
|
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snprintf((char *)ls->ls_device.name, len, "%s_%s", name_prefix, |
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name); |
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ls->ls_device.fops = &device_fops; |
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ls->ls_device.minor = MISC_DYNAMIC_MINOR; |
|
|
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error = misc_register(&ls->ls_device); |
|
if (error) { |
|
kfree(ls->ls_device.name); |
|
/* this has to be set to NULL |
|
* to avoid a double-free in dlm_device_deregister |
|
*/ |
|
ls->ls_device.name = NULL; |
|
} |
|
fail: |
|
return error; |
|
} |
|
|
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int dlm_device_deregister(struct dlm_ls *ls) |
|
{ |
|
/* The device is not registered. This happens when the lockspace |
|
was never used from userspace, or when device_create_lockspace() |
|
calls dlm_release_lockspace() after the register fails. */ |
|
if (!ls->ls_device.name) |
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return 0; |
|
|
|
misc_deregister(&ls->ls_device); |
|
kfree(ls->ls_device.name); |
|
return 0; |
|
} |
|
|
|
static int device_user_purge(struct dlm_user_proc *proc, |
|
struct dlm_purge_params *params) |
|
{ |
|
struct dlm_ls *ls; |
|
int error; |
|
|
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ls = dlm_find_lockspace_local(proc->lockspace); |
|
if (!ls) |
|
return -ENOENT; |
|
|
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error = dlm_user_purge(ls, proc, params->nodeid, params->pid); |
|
|
|
dlm_put_lockspace(ls); |
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return error; |
|
} |
|
|
|
static int device_create_lockspace(struct dlm_lspace_params *params) |
|
{ |
|
dlm_lockspace_t *lockspace; |
|
struct dlm_ls *ls; |
|
int error; |
|
|
|
if (!capable(CAP_SYS_ADMIN)) |
|
return -EPERM; |
|
|
|
error = dlm_new_lockspace(params->name, dlm_config.ci_cluster_name, params->flags, |
|
DLM_USER_LVB_LEN, NULL, NULL, NULL, |
|
&lockspace); |
|
if (error) |
|
return error; |
|
|
|
ls = dlm_find_lockspace_local(lockspace); |
|
if (!ls) |
|
return -ENOENT; |
|
|
|
error = dlm_device_register(ls, params->name); |
|
dlm_put_lockspace(ls); |
|
|
|
if (error) |
|
dlm_release_lockspace(lockspace, 0); |
|
else |
|
error = ls->ls_device.minor; |
|
|
|
return error; |
|
} |
|
|
|
static int device_remove_lockspace(struct dlm_lspace_params *params) |
|
{ |
|
dlm_lockspace_t *lockspace; |
|
struct dlm_ls *ls; |
|
int error, force = 0; |
|
|
|
if (!capable(CAP_SYS_ADMIN)) |
|
return -EPERM; |
|
|
|
ls = dlm_find_lockspace_device(params->minor); |
|
if (!ls) |
|
return -ENOENT; |
|
|
|
if (params->flags & DLM_USER_LSFLG_FORCEFREE) |
|
force = 2; |
|
|
|
lockspace = ls->ls_local_handle; |
|
dlm_put_lockspace(ls); |
|
|
|
/* The final dlm_release_lockspace waits for references to go to |
|
zero, so all processes will need to close their device for the |
|
ls before the release will proceed. release also calls the |
|
device_deregister above. Converting a positive return value |
|
from release to zero means that userspace won't know when its |
|
release was the final one, but it shouldn't need to know. */ |
|
|
|
error = dlm_release_lockspace(lockspace, force); |
|
if (error > 0) |
|
error = 0; |
|
return error; |
|
} |
|
|
|
/* Check the user's version matches ours */ |
|
static int check_version(struct dlm_write_request *req) |
|
{ |
|
if (req->version[0] != DLM_DEVICE_VERSION_MAJOR || |
|
(req->version[0] == DLM_DEVICE_VERSION_MAJOR && |
|
req->version[1] > DLM_DEVICE_VERSION_MINOR)) { |
|
|
|
printk(KERN_DEBUG "dlm: process %s (%d) version mismatch " |
|
"user (%d.%d.%d) kernel (%d.%d.%d)\n", |
|
current->comm, |
|
task_pid_nr(current), |
|
req->version[0], |
|
req->version[1], |
|
req->version[2], |
|
DLM_DEVICE_VERSION_MAJOR, |
|
DLM_DEVICE_VERSION_MINOR, |
|
DLM_DEVICE_VERSION_PATCH); |
|
return -EINVAL; |
|
} |
|
return 0; |
|
} |
|
|
|
/* |
|
* device_write |
|
* |
|
* device_user_lock |
|
* dlm_user_request -> request_lock |
|
* dlm_user_convert -> convert_lock |
|
* |
|
* device_user_unlock |
|
* dlm_user_unlock -> unlock_lock |
|
* dlm_user_cancel -> cancel_lock |
|
* |
|
* device_create_lockspace |
|
* dlm_new_lockspace |
|
* |
|
* device_remove_lockspace |
|
* dlm_release_lockspace |
|
*/ |
|
|
|
/* a write to a lockspace device is a lock or unlock request, a write |
|
to the control device is to create/remove a lockspace */ |
|
|
|
static ssize_t device_write(struct file *file, const char __user *buf, |
|
size_t count, loff_t *ppos) |
|
{ |
|
struct dlm_user_proc *proc = file->private_data; |
|
struct dlm_write_request *kbuf; |
|
int error; |
|
|
|
#ifdef CONFIG_COMPAT |
|
if (count < sizeof(struct dlm_write_request32)) |
|
#else |
|
if (count < sizeof(struct dlm_write_request)) |
|
#endif |
|
return -EINVAL; |
|
|
|
/* |
|
* can't compare against COMPAT/dlm_write_request32 because |
|
* we don't yet know if is64bit is zero |
|
*/ |
|
if (count > sizeof(struct dlm_write_request) + DLM_RESNAME_MAXLEN) |
|
return -EINVAL; |
|
|
|
kbuf = memdup_user_nul(buf, count); |
|
if (IS_ERR(kbuf)) |
|
return PTR_ERR(kbuf); |
|
|
|
if (check_version(kbuf)) { |
|
error = -EBADE; |
|
goto out_free; |
|
} |
|
|
|
#ifdef CONFIG_COMPAT |
|
if (!kbuf->is64bit) { |
|
struct dlm_write_request32 *k32buf; |
|
int namelen = 0; |
|
|
|
if (count > sizeof(struct dlm_write_request32)) |
|
namelen = count - sizeof(struct dlm_write_request32); |
|
|
|
k32buf = (struct dlm_write_request32 *)kbuf; |
|
|
|
/* add 1 after namelen so that the name string is terminated */ |
|
kbuf = kzalloc(sizeof(struct dlm_write_request) + namelen + 1, |
|
GFP_NOFS); |
|
if (!kbuf) { |
|
kfree(k32buf); |
|
return -ENOMEM; |
|
} |
|
|
|
if (proc) |
|
set_bit(DLM_PROC_FLAGS_COMPAT, &proc->flags); |
|
|
|
compat_input(kbuf, k32buf, namelen); |
|
kfree(k32buf); |
|
} |
|
#endif |
|
|
|
/* do we really need this? can a write happen after a close? */ |
|
if ((kbuf->cmd == DLM_USER_LOCK || kbuf->cmd == DLM_USER_UNLOCK) && |
|
(proc && test_bit(DLM_PROC_FLAGS_CLOSING, &proc->flags))) { |
|
error = -EINVAL; |
|
goto out_free; |
|
} |
|
|
|
error = -EINVAL; |
|
|
|
switch (kbuf->cmd) |
|
{ |
|
case DLM_USER_LOCK: |
|
if (!proc) { |
|
log_print("no locking on control device"); |
|
goto out_free; |
|
} |
|
error = device_user_lock(proc, &kbuf->i.lock); |
|
break; |
|
|
|
case DLM_USER_UNLOCK: |
|
if (!proc) { |
|
log_print("no locking on control device"); |
|
goto out_free; |
|
} |
|
error = device_user_unlock(proc, &kbuf->i.lock); |
|
break; |
|
|
|
case DLM_USER_DEADLOCK: |
|
if (!proc) { |
|
log_print("no locking on control device"); |
|
goto out_free; |
|
} |
|
error = device_user_deadlock(proc, &kbuf->i.lock); |
|
break; |
|
|
|
case DLM_USER_CREATE_LOCKSPACE: |
|
if (proc) { |
|
log_print("create/remove only on control device"); |
|
goto out_free; |
|
} |
|
error = device_create_lockspace(&kbuf->i.lspace); |
|
break; |
|
|
|
case DLM_USER_REMOVE_LOCKSPACE: |
|
if (proc) { |
|
log_print("create/remove only on control device"); |
|
goto out_free; |
|
} |
|
error = device_remove_lockspace(&kbuf->i.lspace); |
|
break; |
|
|
|
case DLM_USER_PURGE: |
|
if (!proc) { |
|
log_print("no locking on control device"); |
|
goto out_free; |
|
} |
|
error = device_user_purge(proc, &kbuf->i.purge); |
|
break; |
|
|
|
default: |
|
log_print("Unknown command passed to DLM device : %d\n", |
|
kbuf->cmd); |
|
} |
|
|
|
out_free: |
|
kfree(kbuf); |
|
return error; |
|
} |
|
|
|
/* Every process that opens the lockspace device has its own "proc" structure |
|
hanging off the open file that's used to keep track of locks owned by the |
|
process and asts that need to be delivered to the process. */ |
|
|
|
static int device_open(struct inode *inode, struct file *file) |
|
{ |
|
struct dlm_user_proc *proc; |
|
struct dlm_ls *ls; |
|
|
|
ls = dlm_find_lockspace_device(iminor(inode)); |
|
if (!ls) |
|
return -ENOENT; |
|
|
|
proc = kzalloc(sizeof(struct dlm_user_proc), GFP_NOFS); |
|
if (!proc) { |
|
dlm_put_lockspace(ls); |
|
return -ENOMEM; |
|
} |
|
|
|
proc->lockspace = ls->ls_local_handle; |
|
INIT_LIST_HEAD(&proc->asts); |
|
INIT_LIST_HEAD(&proc->locks); |
|
INIT_LIST_HEAD(&proc->unlocking); |
|
spin_lock_init(&proc->asts_spin); |
|
spin_lock_init(&proc->locks_spin); |
|
init_waitqueue_head(&proc->wait); |
|
file->private_data = proc; |
|
|
|
return 0; |
|
} |
|
|
|
static int device_close(struct inode *inode, struct file *file) |
|
{ |
|
struct dlm_user_proc *proc = file->private_data; |
|
struct dlm_ls *ls; |
|
|
|
ls = dlm_find_lockspace_local(proc->lockspace); |
|
if (!ls) |
|
return -ENOENT; |
|
|
|
set_bit(DLM_PROC_FLAGS_CLOSING, &proc->flags); |
|
|
|
dlm_clear_proc_locks(ls, proc); |
|
|
|
/* at this point no more lkb's should exist for this lockspace, |
|
so there's no chance of dlm_user_add_ast() being called and |
|
looking for lkb->ua->proc */ |
|
|
|
kfree(proc); |
|
file->private_data = NULL; |
|
|
|
dlm_put_lockspace(ls); |
|
dlm_put_lockspace(ls); /* for the find in device_open() */ |
|
|
|
/* FIXME: AUTOFREE: if this ls is no longer used do |
|
device_remove_lockspace() */ |
|
|
|
return 0; |
|
} |
|
|
|
static int copy_result_to_user(struct dlm_user_args *ua, int compat, |
|
uint32_t flags, int mode, int copy_lvb, |
|
char __user *buf, size_t count) |
|
{ |
|
#ifdef CONFIG_COMPAT |
|
struct dlm_lock_result32 result32; |
|
#endif |
|
struct dlm_lock_result result; |
|
void *resultptr; |
|
int error=0; |
|
int len; |
|
int struct_len; |
|
|
|
memset(&result, 0, sizeof(struct dlm_lock_result)); |
|
result.version[0] = DLM_DEVICE_VERSION_MAJOR; |
|
result.version[1] = DLM_DEVICE_VERSION_MINOR; |
|
result.version[2] = DLM_DEVICE_VERSION_PATCH; |
|
memcpy(&result.lksb, &ua->lksb, offsetof(struct dlm_lksb, sb_lvbptr)); |
|
result.user_lksb = ua->user_lksb; |
|
|
|
/* FIXME: dlm1 provides for the user's bastparam/addr to not be updated |
|
in a conversion unless the conversion is successful. See code |
|
in dlm_user_convert() for updating ua from ua_tmp. OpenVMS, though, |
|
notes that a new blocking AST address and parameter are set even if |
|
the conversion fails, so maybe we should just do that. */ |
|
|
|
if (flags & DLM_CB_BAST) { |
|
result.user_astaddr = ua->bastaddr; |
|
result.user_astparam = ua->bastparam; |
|
result.bast_mode = mode; |
|
} else { |
|
result.user_astaddr = ua->castaddr; |
|
result.user_astparam = ua->castparam; |
|
} |
|
|
|
#ifdef CONFIG_COMPAT |
|
if (compat) |
|
len = sizeof(struct dlm_lock_result32); |
|
else |
|
#endif |
|
len = sizeof(struct dlm_lock_result); |
|
struct_len = len; |
|
|
|
/* copy lvb to userspace if there is one, it's been updated, and |
|
the user buffer has space for it */ |
|
|
|
if (copy_lvb && ua->lksb.sb_lvbptr && count >= len + DLM_USER_LVB_LEN) { |
|
if (copy_to_user(buf+len, ua->lksb.sb_lvbptr, |
|
DLM_USER_LVB_LEN)) { |
|
error = -EFAULT; |
|
goto out; |
|
} |
|
|
|
result.lvb_offset = len; |
|
len += DLM_USER_LVB_LEN; |
|
} |
|
|
|
result.length = len; |
|
resultptr = &result; |
|
#ifdef CONFIG_COMPAT |
|
if (compat) { |
|
compat_output(&result, &result32); |
|
resultptr = &result32; |
|
} |
|
#endif |
|
|
|
if (copy_to_user(buf, resultptr, struct_len)) |
|
error = -EFAULT; |
|
else |
|
error = len; |
|
out: |
|
return error; |
|
} |
|
|
|
static int copy_version_to_user(char __user *buf, size_t count) |
|
{ |
|
struct dlm_device_version ver; |
|
|
|
memset(&ver, 0, sizeof(struct dlm_device_version)); |
|
ver.version[0] = DLM_DEVICE_VERSION_MAJOR; |
|
ver.version[1] = DLM_DEVICE_VERSION_MINOR; |
|
ver.version[2] = DLM_DEVICE_VERSION_PATCH; |
|
|
|
if (copy_to_user(buf, &ver, sizeof(struct dlm_device_version))) |
|
return -EFAULT; |
|
return sizeof(struct dlm_device_version); |
|
} |
|
|
|
/* a read returns a single ast described in a struct dlm_lock_result */ |
|
|
|
static ssize_t device_read(struct file *file, char __user *buf, size_t count, |
|
loff_t *ppos) |
|
{ |
|
struct dlm_user_proc *proc = file->private_data; |
|
struct dlm_lkb *lkb; |
|
DECLARE_WAITQUEUE(wait, current); |
|
struct dlm_callback cb; |
|
int rv, resid, copy_lvb = 0; |
|
int old_mode, new_mode; |
|
|
|
if (count == sizeof(struct dlm_device_version)) { |
|
rv = copy_version_to_user(buf, count); |
|
return rv; |
|
} |
|
|
|
if (!proc) { |
|
log_print("non-version read from control device %zu", count); |
|
return -EINVAL; |
|
} |
|
|
|
#ifdef CONFIG_COMPAT |
|
if (count < sizeof(struct dlm_lock_result32)) |
|
#else |
|
if (count < sizeof(struct dlm_lock_result)) |
|
#endif |
|
return -EINVAL; |
|
|
|
try_another: |
|
|
|
/* do we really need this? can a read happen after a close? */ |
|
if (test_bit(DLM_PROC_FLAGS_CLOSING, &proc->flags)) |
|
return -EINVAL; |
|
|
|
spin_lock(&proc->asts_spin); |
|
if (list_empty(&proc->asts)) { |
|
if (file->f_flags & O_NONBLOCK) { |
|
spin_unlock(&proc->asts_spin); |
|
return -EAGAIN; |
|
} |
|
|
|
add_wait_queue(&proc->wait, &wait); |
|
|
|
repeat: |
|
set_current_state(TASK_INTERRUPTIBLE); |
|
if (list_empty(&proc->asts) && !signal_pending(current)) { |
|
spin_unlock(&proc->asts_spin); |
|
schedule(); |
|
spin_lock(&proc->asts_spin); |
|
goto repeat; |
|
} |
|
set_current_state(TASK_RUNNING); |
|
remove_wait_queue(&proc->wait, &wait); |
|
|
|
if (signal_pending(current)) { |
|
spin_unlock(&proc->asts_spin); |
|
return -ERESTARTSYS; |
|
} |
|
} |
|
|
|
/* if we empty lkb_callbacks, we don't want to unlock the spinlock |
|
without removing lkb_cb_list; so empty lkb_cb_list is always |
|
consistent with empty lkb_callbacks */ |
|
|
|
lkb = list_entry(proc->asts.next, struct dlm_lkb, lkb_cb_list); |
|
|
|
/* rem_lkb_callback sets a new lkb_last_cast */ |
|
old_mode = lkb->lkb_last_cast.mode; |
|
|
|
rv = dlm_rem_lkb_callback(lkb->lkb_resource->res_ls, lkb, &cb, &resid); |
|
if (rv < 0) { |
|
/* this shouldn't happen; lkb should have been removed from |
|
list when resid was zero */ |
|
log_print("dlm_rem_lkb_callback empty %x", lkb->lkb_id); |
|
list_del_init(&lkb->lkb_cb_list); |
|
spin_unlock(&proc->asts_spin); |
|
/* removes ref for proc->asts, may cause lkb to be freed */ |
|
dlm_put_lkb(lkb); |
|
goto try_another; |
|
} |
|
if (!resid) |
|
list_del_init(&lkb->lkb_cb_list); |
|
spin_unlock(&proc->asts_spin); |
|
|
|
if (cb.flags & DLM_CB_SKIP) { |
|
/* removes ref for proc->asts, may cause lkb to be freed */ |
|
if (!resid) |
|
dlm_put_lkb(lkb); |
|
goto try_another; |
|
} |
|
|
|
if (cb.flags & DLM_CB_CAST) { |
|
new_mode = cb.mode; |
|
|
|
if (!cb.sb_status && lkb->lkb_lksb->sb_lvbptr && |
|
dlm_lvb_operations[old_mode + 1][new_mode + 1]) |
|
copy_lvb = 1; |
|
|
|
lkb->lkb_lksb->sb_status = cb.sb_status; |
|
lkb->lkb_lksb->sb_flags = cb.sb_flags; |
|
} |
|
|
|
rv = copy_result_to_user(lkb->lkb_ua, |
|
test_bit(DLM_PROC_FLAGS_COMPAT, &proc->flags), |
|
cb.flags, cb.mode, copy_lvb, buf, count); |
|
|
|
/* removes ref for proc->asts, may cause lkb to be freed */ |
|
if (!resid) |
|
dlm_put_lkb(lkb); |
|
|
|
return rv; |
|
} |
|
|
|
static __poll_t device_poll(struct file *file, poll_table *wait) |
|
{ |
|
struct dlm_user_proc *proc = file->private_data; |
|
|
|
poll_wait(file, &proc->wait, wait); |
|
|
|
spin_lock(&proc->asts_spin); |
|
if (!list_empty(&proc->asts)) { |
|
spin_unlock(&proc->asts_spin); |
|
return EPOLLIN | EPOLLRDNORM; |
|
} |
|
spin_unlock(&proc->asts_spin); |
|
return 0; |
|
} |
|
|
|
int dlm_user_daemon_available(void) |
|
{ |
|
/* dlm_controld hasn't started (or, has started, but not |
|
properly populated configfs) */ |
|
|
|
if (!dlm_our_nodeid()) |
|
return 0; |
|
|
|
/* This is to deal with versions of dlm_controld that don't |
|
know about the monitor device. We assume that if the |
|
dlm_controld was started (above), but the monitor device |
|
was never opened, that it's an old version. dlm_controld |
|
should open the monitor device before populating configfs. */ |
|
|
|
if (dlm_monitor_unused) |
|
return 1; |
|
|
|
return atomic_read(&dlm_monitor_opened) ? 1 : 0; |
|
} |
|
|
|
static int ctl_device_open(struct inode *inode, struct file *file) |
|
{ |
|
file->private_data = NULL; |
|
return 0; |
|
} |
|
|
|
static int ctl_device_close(struct inode *inode, struct file *file) |
|
{ |
|
return 0; |
|
} |
|
|
|
static int monitor_device_open(struct inode *inode, struct file *file) |
|
{ |
|
atomic_inc(&dlm_monitor_opened); |
|
dlm_monitor_unused = 0; |
|
return 0; |
|
} |
|
|
|
static int monitor_device_close(struct inode *inode, struct file *file) |
|
{ |
|
if (atomic_dec_and_test(&dlm_monitor_opened)) |
|
dlm_stop_lockspaces(); |
|
return 0; |
|
} |
|
|
|
static const struct file_operations device_fops = { |
|
.open = device_open, |
|
.release = device_close, |
|
.read = device_read, |
|
.write = device_write, |
|
.poll = device_poll, |
|
.owner = THIS_MODULE, |
|
.llseek = noop_llseek, |
|
}; |
|
|
|
static const struct file_operations ctl_device_fops = { |
|
.open = ctl_device_open, |
|
.release = ctl_device_close, |
|
.read = device_read, |
|
.write = device_write, |
|
.owner = THIS_MODULE, |
|
.llseek = noop_llseek, |
|
}; |
|
|
|
static struct miscdevice ctl_device = { |
|
.name = "dlm-control", |
|
.fops = &ctl_device_fops, |
|
.minor = MISC_DYNAMIC_MINOR, |
|
}; |
|
|
|
static const struct file_operations monitor_device_fops = { |
|
.open = monitor_device_open, |
|
.release = monitor_device_close, |
|
.owner = THIS_MODULE, |
|
.llseek = noop_llseek, |
|
}; |
|
|
|
static struct miscdevice monitor_device = { |
|
.name = "dlm-monitor", |
|
.fops = &monitor_device_fops, |
|
.minor = MISC_DYNAMIC_MINOR, |
|
}; |
|
|
|
int __init dlm_user_init(void) |
|
{ |
|
int error; |
|
|
|
atomic_set(&dlm_monitor_opened, 0); |
|
|
|
error = misc_register(&ctl_device); |
|
if (error) { |
|
log_print("misc_register failed for control device"); |
|
goto out; |
|
} |
|
|
|
error = misc_register(&monitor_device); |
|
if (error) { |
|
log_print("misc_register failed for monitor device"); |
|
misc_deregister(&ctl_device); |
|
} |
|
out: |
|
return error; |
|
} |
|
|
|
void dlm_user_exit(void) |
|
{ |
|
misc_deregister(&ctl_device); |
|
misc_deregister(&monitor_device); |
|
} |
|
|
|
|