fs/afs/server_list.c

Source file repositories/reference/linux-study-clean/fs/afs/server_list.c

File Facts

System
Linux kernel
Corpus path
fs/afs/server_list.c
Extension
.c
Size
6333 bytes
Lines
250
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.

Dependency Surface

Detected Declarations

Annotated Snippet

if (newrep < usable / 2) {
			slist->ro_replicating = AFS_RO_REPLICATING_USE_OLD;
		} else {
			slist->ro_replicating = AFS_RO_REPLICATING_USE_NEW;
			use_newrepsites = true;
		}
	}

	refcount_set(&slist->usage, 1);
	rwlock_init(&slist->lock);

	/* Make sure a records exists for each server in the list. */
	for (i = 0; i < vldb->nr_servers; i++) {
		unsigned long se_flags = 0;
		bool newrepsite = vldb->vlsf_flags[i] & AFS_VLSF_NEWREPSITE;

		if (!(vldb->fs_mask[i] & type_mask))
			continue;
		if (vldb->vlsf_flags[i] & AFS_VLSF_DONTUSE)
			__set_bit(AFS_SE_EXCLUDED, &se_flags);
		if (newrep && (newrepsite ^ use_newrepsites))
			__set_bit(AFS_SE_EXCLUDED, &se_flags);

		server = afs_lookup_server(volume->cell, key, &vldb->fs_server[i],
					   vldb->addr_version[i]);
		if (IS_ERR(server)) {
			ret = PTR_ERR(server);
			if (ret == -ENOENT ||
			    ret == -ENOMEDIUM)
				continue;
			goto error_2;
		}

		/* Insertion-sort by UUID */
		for (j = 0; j < slist->nr_servers; j++)
			if (memcmp(&slist->servers[j].server->uuid,
				   &server->uuid,
				   sizeof(server->uuid)) >= 0)
				break;
		if (j < slist->nr_servers) {
			if (slist->servers[j].server == server) {
				afs_unuse_server_notime(volume->cell->net, server,
							afs_server_trace_unuse_slist_isort);
				continue;
			}

			memmove(slist->servers + j + 1,
				slist->servers + j,
				(slist->nr_servers - j) * sizeof(struct afs_server_entry));
		}

		slist->servers[j].server = server;
		slist->servers[j].volume = volume;
		slist->servers[j].flags = se_flags;
		slist->servers[j].cb_expires_at = AFS_NO_CB_PROMISE;
		slist->nr_servers++;
	}

	if (slist->nr_servers == 0) {
		ret = -EDESTADDRREQ;
		goto error_2;
	}

	return slist;

error_2:
	afs_put_serverlist(volume->cell->net, slist);
error:
	return ERR_PTR(ret);
}

/*
 * Copy the annotations from an old server list to its potential replacement.
 */
bool afs_annotate_server_list(struct afs_server_list *new,
			      struct afs_server_list *old)
{
	unsigned long mask = 1UL << AFS_SE_EXCLUDED;
	int i;

	if (old->nr_servers != new->nr_servers ||
	    old->ro_replicating != new->ro_replicating)
		goto changed;

	for (i = 0; i < old->nr_servers; i++) {
		if (old->servers[i].server != new->servers[i].server)
			goto changed;
		if ((old->servers[i].flags & mask) != (new->servers[i].flags & mask))
			goto changed;
	}

Annotation

Implementation Notes