Commit c10a7514 authored by Frank van der Linden's avatar Frank van der Linden Committed by Trond Myklebust
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NFSv4.2: add the extended attribute proc functions. 



Implement the extended attribute procedures for NFSv4.2 extended
attribute support (RFC 8276).

Signed-off-by: default avatarFrank van der Linden <fllinden@amazon.com>
Signed-off-by: default avatarTrond Myklebust <trond.myklebust@hammerspace.com>
parent ccde1e9c

fs/nfs/nfs42.h

+8 −0
Original line number Diff line number Diff line
@@ -39,6 +39,14 @@ static inline bool nfs42_files_from_same_server(struct file *in, 
					       c_out->cl_serverowner);

}



ssize_t nfs42_proc_getxattr(struct inode *inode, const char *name,

			    void *buf, size_t buflen);

int nfs42_proc_setxattr(struct inode *inode, const char *name,

			const void *buf, size_t buflen, int flags);

ssize_t nfs42_proc_listxattrs(struct inode *inode, void *buf,

			       size_t buflen, u64 *cookiep, bool *eofp);

int nfs42_proc_removexattr(struct inode *inode, const char *name);



/*

 * Maximum XDR buffer size needed for a listxattr buffer of buflen size.

 *

fs/nfs/nfs42proc.c

+236 −0
Original line number Diff line number Diff line
@@ -1088,3 +1088,239 @@ int nfs42_proc_clone(struct file *src_f, struct file *dst_f, 
	nfs_put_lock_context(src_lock);

	return err;

}



#define NFS4XATTR_MAXPAGES DIV_ROUND_UP(XATTR_SIZE_MAX, PAGE_SIZE)



static int _nfs42_proc_removexattr(struct inode *inode, const char *name)

{

	struct nfs_server *server = NFS_SERVER(inode);

	struct nfs42_removexattrargs args = {

		.fh = NFS_FH(inode),

		.xattr_name = name,

	};

	struct nfs42_removexattrres res;

	struct rpc_message msg = {

		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_REMOVEXATTR],

		.rpc_argp = &args,

		.rpc_resp = &res,

	};

	int ret;

	unsigned long timestamp = jiffies;



	ret = nfs4_call_sync(server->client, server, &msg, &args.seq_args,

	    &res.seq_res, 1);

	if (!ret)

		nfs4_update_changeattr(inode, &res.cinfo, timestamp, 0);



	return ret;

}



static int _nfs42_proc_setxattr(struct inode *inode, const char *name,

				const void *buf, size_t buflen, int flags)

{

	struct nfs_server *server = NFS_SERVER(inode);

	struct page *pages[NFS4XATTR_MAXPAGES];

	struct nfs42_setxattrargs arg = {

		.fh		= NFS_FH(inode),

		.xattr_pages	= pages,

		.xattr_len	= buflen,

		.xattr_name	= name,

		.xattr_flags	= flags,

	};

	struct nfs42_setxattrres res;

	struct rpc_message msg = {

		.rpc_proc	= &nfs4_procedures[NFSPROC4_CLNT_SETXATTR],

		.rpc_argp	= &arg,

		.rpc_resp	= &res,

	};

	int ret, np;

	unsigned long timestamp = jiffies;



	if (buflen > server->sxasize)

		return -ERANGE;



	if (buflen > 0) {

		np = nfs4_buf_to_pages_noslab(buf, buflen, arg.xattr_pages);

		if (np < 0)

			return np;

	} else

		np = 0;



	ret = nfs4_call_sync(server->client, server, &msg, &arg.seq_args,

	    &res.seq_res, 1);



	for (; np > 0; np--)

		put_page(pages[np - 1]);



	if (!ret)

		nfs4_update_changeattr(inode, &res.cinfo, timestamp, 0);



	return ret;

}



static ssize_t _nfs42_proc_getxattr(struct inode *inode, const char *name,

				void *buf, size_t buflen)

{

	struct nfs_server *server = NFS_SERVER(inode);

	struct page *pages[NFS4XATTR_MAXPAGES] = {};

	struct nfs42_getxattrargs arg = {

		.fh		= NFS_FH(inode),

		.xattr_pages	= pages,

		.xattr_len	= buflen,

		.xattr_name	= name,

	};

	struct nfs42_getxattrres res;

	struct rpc_message msg = {

		.rpc_proc	= &nfs4_procedures[NFSPROC4_CLNT_GETXATTR],

		.rpc_argp	= &arg,

		.rpc_resp	= &res,

	};

	int ret, np;



	ret = nfs4_call_sync(server->client, server, &msg, &arg.seq_args,

	    &res.seq_res, 0);

	if (ret < 0)

		return ret;



	if (buflen) {

		if (res.xattr_len > buflen)

			return -ERANGE;

		_copy_from_pages(buf, pages, 0, res.xattr_len);

	}



	np = DIV_ROUND_UP(res.xattr_len, PAGE_SIZE);

	while (--np >= 0)

		__free_page(pages[np]);



	return res.xattr_len;

}



static ssize_t _nfs42_proc_listxattrs(struct inode *inode, void *buf,

				 size_t buflen, u64 *cookiep, bool *eofp)

{

	struct nfs_server *server = NFS_SERVER(inode);

	struct page **pages;

	struct nfs42_listxattrsargs arg = {

		.fh		= NFS_FH(inode),

		.cookie		= *cookiep,

	};

	struct nfs42_listxattrsres res = {

		.eof = false,

		.xattr_buf = buf,

		.xattr_len = buflen,

	};

	struct rpc_message msg = {

		.rpc_proc	= &nfs4_procedures[NFSPROC4_CLNT_LISTXATTRS],

		.rpc_argp	= &arg,

		.rpc_resp	= &res,

	};

	u32 xdrlen;

	int ret, np;





	res.scratch = alloc_page(GFP_KERNEL);

	if (!res.scratch)

		return -ENOMEM;



	xdrlen = nfs42_listxattr_xdrsize(buflen);

	if (xdrlen > server->lxasize)

		xdrlen = server->lxasize;

	np = xdrlen / PAGE_SIZE + 1;



	pages = kcalloc(np, sizeof(struct page *), GFP_KERNEL);

	if (pages == NULL) {

		__free_page(res.scratch);

		return -ENOMEM;

	}



	arg.xattr_pages = pages;

	arg.count = xdrlen;



	ret = nfs4_call_sync(server->client, server, &msg, &arg.seq_args,

	    &res.seq_res, 0);



	if (ret >= 0) {

		ret = res.copied;

		*cookiep = res.cookie;

		*eofp = res.eof;

	}



	while (--np >= 0) {

		if (pages[np])

			__free_page(pages[np]);

	}



	__free_page(res.scratch);

	kfree(pages);



	return ret;



}



ssize_t nfs42_proc_getxattr(struct inode *inode, const char *name,

			      void *buf, size_t buflen)

{

	struct nfs4_exception exception = { };

	ssize_t err;



	do {

		err = _nfs42_proc_getxattr(inode, name, buf, buflen);

		if (err >= 0)

			break;

		err = nfs4_handle_exception(NFS_SERVER(inode), err,

				&exception);

	} while (exception.retry);



	return err;

}



int nfs42_proc_setxattr(struct inode *inode, const char *name,

			      const void *buf, size_t buflen, int flags)

{

	struct nfs4_exception exception = { };

	int err;



	do {

		err = _nfs42_proc_setxattr(inode, name, buf, buflen, flags);

		if (!err)

			break;

		err = nfs4_handle_exception(NFS_SERVER(inode), err,

				&exception);

	} while (exception.retry);



	return err;

}



ssize_t nfs42_proc_listxattrs(struct inode *inode, void *buf,

			      size_t buflen, u64 *cookiep, bool *eofp)

{

	struct nfs4_exception exception = { };

	ssize_t err;



	do {

		err = _nfs42_proc_listxattrs(inode, buf, buflen,

		    cookiep, eofp);

		if (err >= 0)

			break;

		err = nfs4_handle_exception(NFS_SERVER(inode), err,

				&exception);

	} while (exception.retry);



	return err;

}



int nfs42_proc_removexattr(struct inode *inode, const char *name)

{

	struct nfs4_exception exception = { };

	int err;



	do {

		err = _nfs42_proc_removexattr(inode, name);

		if (!err)

			break;

		err = nfs4_handle_exception(NFS_SERVER(inode), err,

				&exception);

	} while (exception.retry);



	return err;

}