fs/smb/client/dfs.c

Source file repositories/reference/linux-study-clean/fs/smb/client/dfs.c

File Facts

System
Linux kernel
Corpus path
fs/smb/client/dfs.c
Extension
.c
Size
11560 bytes
Lines
468
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

while (ref_walk_next_tgt(rw)) {
			rc = parse_dfs_target(ctx, rw, &tgt);
			if (rc)
				continue;

			cifs_mount_put_conns(mnt_ctx);
			rc = get_session(mnt_ctx, ref_walk_path(rw));
			if (rc)
				continue;

			rc = cifs_mount_get_tcon(mnt_ctx);
			if (rc) {
				if (tgt.server_type == DFS_TYPE_LINK &&
				    DFS_INTERLINK(tgt.flags))
					rc = -EREMOTE;
			} else {
				rc = cifs_is_path_remote(mnt_ctx);
				if (!rc) {
					ref_walk_set_tgt_hint(rw);
					break;
				}
			}
			if (rc == -EREMOTE) {
				rc = ref_walk_advance(rw);
				if (!rc) {
					rc = setup_dfs_ref(&tgt, rw);
					if (rc)
						break;
					ref_walk_mark_end(rw);
					goto again;
				}
			}
		}
	} while (rc && ref_walk_descend(rw));

	free_dfs_info_param(&tgt);
	return rc;
}

static int dfs_referral_walk(struct cifs_mount_ctx *mnt_ctx,
			     struct dfs_ref_walk **rw)
{
	int rc;

	*rw = ref_walk_alloc();
	if (IS_ERR(*rw)) {
		rc = PTR_ERR(*rw);
		*rw = NULL;
		return rc;
	}

	ref_walk_init(*rw, mnt_ctx);
	rc = setup_dfs_ref(NULL, *rw);
	if (!rc)
		rc = __dfs_referral_walk(*rw);
	return rc;
}

static int __dfs_mount_share(struct cifs_mount_ctx *mnt_ctx)
{
	struct cifs_sb_info *cifs_sb = mnt_ctx->cifs_sb;
	struct smb3_fs_context *ctx = mnt_ctx->fs_ctx;
	struct dfs_ref_walk *rw = NULL;
	struct cifs_tcon *tcon;
	char *origin_fullpath;
	int rc;

	origin_fullpath = dfs_get_path(cifs_sb, ctx->source);
	if (IS_ERR(origin_fullpath))
		return PTR_ERR(origin_fullpath);

	rc = dfs_referral_walk(mnt_ctx, &rw);
	if (!rc) {
		/*
		 * Prevent superblock from being created with any missing
		 * connections.
		 */
		if (WARN_ON(!mnt_ctx->server))
			rc = -EHOSTDOWN;
		else if (WARN_ON(!mnt_ctx->ses))
			rc = -EACCES;
		else if (WARN_ON(!mnt_ctx->tcon))
			rc = -ENOENT;
	}
	if (rc)
		goto out;

	tcon = mnt_ctx->tcon;
	spin_lock(&tcon->tc_lock);
	tcon->origin_fullpath = origin_fullpath;

Annotation

Implementation Notes