fs/nfsd/nfs3xdr.c

Source file repositories/reference/linux-study-clean/fs/nfsd/nfs3xdr.c

File Facts

System
Linux kernel
Corpus path
fs/nfsd/nfs3xdr.c
Extension
.c
Size
31953 bytes
Lines
1357
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 (namlen == 2) {
			dchild = dget_parent(dparent);
			/*
			 * Don't return filehandle for ".." if we're at
			 * the filesystem or export root:
			 */
			if (dchild == dparent)
				goto out;
			if (dparent == exp->ex_path.dentry)
				goto out;
		} else
			dchild = dget(dparent);
	} else
		dchild = lookup_one_positive_unlocked(&nop_mnt_idmap,
						      &QSTR_LEN(name, namlen),
						      dparent);
	if (IS_ERR(dchild))
		return rv;
	if (d_mountpoint(dchild))
		goto out;
	if (dchild->d_inode->i_ino != ino)
		goto out;
	rv = fh_compose(fhp, exp, dchild, &cd->fh);
out:
	dput(dchild);
	return rv;
}

/**
 * nfs3svc_encode_cookie3 - Encode a directory offset cookie
 * @resp: readdir result context
 * @offset: offset cookie to encode
 *
 * The buffer space for the offset cookie has already been reserved
 * by svcxdr_encode_entry3_common().
 */
void nfs3svc_encode_cookie3(struct nfsd3_readdirres *resp, u64 offset)
{
	__be64 cookie = cpu_to_be64(offset);

	if (!resp->cookie_offset)
		return;
	write_bytes_to_xdr_buf(&resp->dirlist, resp->cookie_offset, &cookie,
			       sizeof(cookie));
	resp->cookie_offset = 0;
}

static bool
svcxdr_encode_entry3_common(struct nfsd3_readdirres *resp, const char *name,
			    int namlen, loff_t offset, u64 ino)
{
	struct xdr_buf *dirlist = &resp->dirlist;
	struct xdr_stream *xdr = &resp->xdr;

	if (xdr_stream_encode_item_present(xdr) < 0)
		return false;
	/* fileid */
	if (xdr_stream_encode_u64(xdr, ino) < 0)
		return false;
	/* name */
	if (xdr_stream_encode_opaque(xdr, name, min(namlen, NFS3_MAXNAMLEN)) < 0)
		return false;
	/* cookie */
	resp->cookie_offset = dirlist->len;
	if (xdr_stream_encode_u64(xdr, OFFSET_MAX) < 0)
		return false;

	return true;
}

/**
 * nfs3svc_encode_entry3 - encode one NFSv3 READDIR entry
 * @data: directory context
 * @name: name of the object to be encoded
 * @namlen: length of that name, in bytes
 * @offset: the offset of the previous entry
 * @ino: the fileid of this entry
 * @d_type: unused
 *
 * Return values:
 *   %0: Entry was successfully encoded.
 *   %-EINVAL: An encoding problem occurred, secondary status code in resp->common.err
 *
 * On exit, the following fields are updated:
 *   - resp->xdr
 *   - resp->common.err
 *   - resp->cookie_offset
 */
int nfs3svc_encode_entry3(void *data, const char *name, int namlen,
			  loff_t offset, u64 ino, unsigned int d_type)

Annotation

Implementation Notes