fs/ocfs2/dlm/dlmast.c
Source file repositories/reference/linux-study-clean/fs/ocfs2/dlm/dlmast.c
File Facts
- System
- Linux kernel
- Corpus path
fs/ocfs2/dlm/dlmast.c- Extension
.c- Size
- 13617 bytes
- Lines
- 476
- Domain
- Core OS
- Bucket
- VFS And Filesystem Core
- Inferred role
- Core OS: implementation source
- Status
- source implementation candidate
Why This File Exists
Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.
- Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.
- Uses kernel synchronization; read lock ordering, sleepability, and interrupt context assumptions before translating.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
linux/module.hlinux/fs.hlinux/types.hlinux/highmem.hlinux/init.hlinux/sysctl.hlinux/random.hlinux/blkdev.hlinux/socket.hlinux/inet.hlinux/spinlock.h../cluster/heartbeat.h../cluster/nodemanager.h../cluster/tcp.hdlmapi.hdlmcommon.h../cluster/masklog.h
Detected Declarations
function dlm_should_cancel_bastfunction __dlm_queue_astfunction dlm_queue_astfunction __dlm_queue_bastfunction dlm_update_lvbfunction dlm_do_local_astfunction dlm_do_remote_astfunction dlm_do_local_bastfunction dlm_proxy_ast_handlerfunction list_for_each_entryfunction dlm_send_proxy_ast_msg
Annotated Snippet
if (lksb->flags & DLM_LKSB_GET_LVB) {
mlog(0, "getting lvb from lockres for %s node\n",
lock->ml.node == dlm->node_num ? "master" :
"remote");
memcpy(lksb->lvb, res->lvb, DLM_LVB_LEN);
}
/* Do nothing for lvb put requests - they should be done in
* place when the lock is downconverted - otherwise we risk
* racing gets and puts which could result in old lvb data
* being propagated. We leave the put flag set and clear it
* here. In the future we might want to clear it at the time
* the put is actually done.
*/
}
spin_unlock(&res->spinlock);
/* reset any lvb flags on the lksb */
lksb->flags &= ~(DLM_LKSB_PUT_LVB|DLM_LKSB_GET_LVB);
}
void dlm_do_local_ast(struct dlm_ctxt *dlm, struct dlm_lock_resource *res,
struct dlm_lock *lock)
{
dlm_astlockfunc_t *fn;
mlog(0, "%s: res %.*s, lock %u:%llu, Local AST\n", dlm->name,
res->lockname.len, res->lockname.name,
dlm_get_lock_cookie_node(be64_to_cpu(lock->ml.cookie)),
dlm_get_lock_cookie_seq(be64_to_cpu(lock->ml.cookie)));
fn = lock->ast;
BUG_ON(lock->ml.node != dlm->node_num);
dlm_update_lvb(dlm, res, lock);
(*fn)(lock->astdata);
}
int dlm_do_remote_ast(struct dlm_ctxt *dlm, struct dlm_lock_resource *res,
struct dlm_lock *lock)
{
int ret;
struct dlm_lockstatus *lksb;
int lksbflags;
mlog(0, "%s: res %.*s, lock %u:%llu, Remote AST\n", dlm->name,
res->lockname.len, res->lockname.name,
dlm_get_lock_cookie_node(be64_to_cpu(lock->ml.cookie)),
dlm_get_lock_cookie_seq(be64_to_cpu(lock->ml.cookie)));
lksb = lock->lksb;
BUG_ON(lock->ml.node == dlm->node_num);
lksbflags = lksb->flags;
dlm_update_lvb(dlm, res, lock);
/* lock request came from another node
* go do the ast over there */
ret = dlm_send_proxy_ast(dlm, res, lock, lksbflags);
return ret;
}
void dlm_do_local_bast(struct dlm_ctxt *dlm, struct dlm_lock_resource *res,
struct dlm_lock *lock, int blocked_type)
{
dlm_bastlockfunc_t *fn = lock->bast;
BUG_ON(lock->ml.node != dlm->node_num);
mlog(0, "%s: res %.*s, lock %u:%llu, Local BAST, blocked %d\n",
dlm->name, res->lockname.len, res->lockname.name,
dlm_get_lock_cookie_node(be64_to_cpu(lock->ml.cookie)),
dlm_get_lock_cookie_seq(be64_to_cpu(lock->ml.cookie)),
blocked_type);
(*fn)(lock->astdata, blocked_type);
}
int dlm_proxy_ast_handler(struct o2net_msg *msg, u32 len, void *data,
void **ret_data)
{
int ret;
unsigned int locklen;
struct dlm_ctxt *dlm = data;
struct dlm_lock_resource *res = NULL;
struct dlm_lock *lock = NULL;
struct dlm_proxy_ast *past = (struct dlm_proxy_ast *) msg->buf;
char *name;
Annotation
- Immediate include surface: `linux/module.h`, `linux/fs.h`, `linux/types.h`, `linux/highmem.h`, `linux/init.h`, `linux/sysctl.h`, `linux/random.h`, `linux/blkdev.h`.
- Detected declarations: `function dlm_should_cancel_bast`, `function __dlm_queue_ast`, `function dlm_queue_ast`, `function __dlm_queue_bast`, `function dlm_update_lvb`, `function dlm_do_local_ast`, `function dlm_do_remote_ast`, `function dlm_do_local_bast`, `function dlm_proxy_ast_handler`, `function list_for_each_entry`.
- Atlas domain: Core OS / VFS And Filesystem Core.
- Implementation status: source implementation candidate.
- Synchronization appears in or near this file; preserve lock ordering, sleepability, and interrupt-context constraints.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.