[PATCH v3 0/3] NFSv4.2: Add support for the COPY operation

[PATCH v3 0/3] NFSv4.2: Add support for the COPY operation

[Anna Schumaker]

These patches add client and server support for the NFS v4.2 COPY operation,
and make use of the new copy_file_range() system call.

Changes in v3:
- Add nfs_commit_file() function to sent a commit after a copy.
- Update exception handling to match Christoph's recent changes.
- Server should check for copying beyond the end of the file.

Questions, comments, and other testing ideas would be greatly appreciated!

Thanks,
Anna


Anna Schumaker (4):
  NFS: Add nfs_commit_file()
  NFS: Add COPY nfs operation
  NFSD: Implement the COPY call
  vfs_copy_range() test program

 fs/nfs/internal.h         |   1 +
 fs/nfs/nfs42.h            |   1 +
 fs/nfs/nfs42proc.c        | 105 +++++++++++++++++++++++++++++++++
 fs/nfs/nfs42xdr.c         | 146 ++++++++++++++++++++++++++++++++++++++++++++++
 fs/nfs/nfs4file.c         |  23 ++++++++
 fs/nfs/nfs4proc.c         |   1 +
 fs/nfs/nfs4xdr.c          |   1 +
 fs/nfs/pagelist.c         |   6 +-
 fs/nfs/write.c            |  41 +++++++++++--
 fs/nfsd/nfs4proc.c        |  98 +++++++++++++++++++++++++++----
 fs/nfsd/nfs4xdr.c         |  63 +++++++++++++++++++-
 fs/nfsd/vfs.c             |   6 ++
 fs/nfsd/vfs.h             |   1 +
 fs/nfsd/xdr4.h            |  23 ++++++++
 include/linux/nfs4.h      |   1 +
 include/linux/nfs_fs_sb.h |   1 +
 include/linux/nfs_xdr.h   |  26 +++++++++
 nfscopy.c                 |  59 +++++++++++++++++++
 18 files changed, 584 insertions(+), 19 deletions(-)
 create mode 100644 nfscopy.c

-- 
2.7.2

[PATCH v3 1/3] NFS: Add nfs_commit_file()

[Anna Schumaker]

Copy will use this to set up a commit request for a generic range.  I
don't want to allocate a new pagecache entry for the file, so I needed
to change parts of the commit path to handle requests with a null
wb_page.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
---
Checking for wb_page everywhere feels like a hack, but I don't really see
any other way of doing this.  Suggestions welcome!
---
 fs/nfs/internal.h |  1 +
 fs/nfs/pagelist.c |  6 ++++--
 fs/nfs/write.c    | 41 +++++++++++++++++++++++++++++++++++++----
 3 files changed, 42 insertions(+), 6 deletions(-)

diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index 9a547aa..7a3778c 100644
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -477,6 +477,7 @@ void nfs_mark_request_commit(struct nfs_page *req,
 			     u32 ds_commit_idx);
 int nfs_write_need_commit(struct nfs_pgio_header *);
 void nfs_writeback_update_inode(struct nfs_pgio_header *hdr);
+int nfs_commit_file(struct file *file, struct nfs_write_verifier *verf);
 int nfs_generic_commit_list(struct inode *inode, struct list_head *head,
 			    int how, struct nfs_commit_info *cinfo);
 void nfs_retry_commit(struct list_head *page_list,
diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c
index 8ce4f61..c3c3555 100644
--- a/fs/nfs/pagelist.c
+++ b/fs/nfs/pagelist.c
@@ -341,8 +341,10 @@ nfs_create_request(struct nfs_open_context *ctx, struct page *page,
 	 * long write-back delay. This will be adjusted in
 	 * update_nfs_request below if the region is not locked. */
 	req->wb_page    = page;
-	req->wb_index	= page_file_index(page);
-	page_cache_get(page);
+	if (page) {
+		req->wb_index = page_file_index(page);
+		page_cache_get(page);
+	}
 	req->wb_offset  = offset;
 	req->wb_pgbase	= offset;
 	req->wb_bytes   = count;
diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index 5754835..a82765b9 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -737,7 +737,7 @@ static void nfs_inode_remove_request(struct nfs_page *req)
 		head = req->wb_head;
 
 		spin_lock(&inode->i_lock);
-		if (likely(!PageSwapCache(head->wb_page))) {
+		if (likely(head->wb_page && !PageSwapCache(head->wb_page))) {
 			set_page_private(head->wb_page, 0);
 			ClearPagePrivate(head->wb_page);
 			smp_mb__after_atomic();
@@ -759,7 +759,8 @@ static void nfs_inode_remove_request(struct nfs_page *req)
 static void
 nfs_mark_request_dirty(struct nfs_page *req)
 {
-	__set_page_dirty_nobuffers(req->wb_page);
+	if (req->wb_page)
+		__set_page_dirty_nobuffers(req->wb_page);
 }
 
 /*
@@ -835,7 +836,8 @@ nfs_request_add_commit_list(struct nfs_page *req, struct nfs_commit_info *cinfo)
 	spin_lock(cinfo->lock);
 	nfs_request_add_commit_list_locked(req, &cinfo->mds->list, cinfo);
 	spin_unlock(cinfo->lock);
-	nfs_mark_page_unstable(req->wb_page, cinfo);
+	if (req->wb_page)
+		nfs_mark_page_unstable(req->wb_page, cinfo);
 }
 EXPORT_SYMBOL_GPL(nfs_request_add_commit_list);
 
@@ -1724,6 +1726,36 @@ nfs_commit_list(struct inode *inode, struct list_head *head, int how,
 	return -ENOMEM;
 }
 
+int nfs_commit_file(struct file *file, struct nfs_write_verifier *verf)
+{
+	struct inode *inode = file_inode(file);
+	struct nfs_open_context *open;
+	struct nfs_commit_info cinfo;
+	struct nfs_page *req;
+	int ret;
+
+	open = get_nfs_open_context(nfs_file_open_context(file));
+	req  = nfs_create_request(open, NULL, NULL, 0, i_size_read(inode));
+	if (!req) {
+		ret = -ENOMEM;
+		goto out_put;
+	}
+
+	nfs_init_cinfo_from_inode(&cinfo, inode);
+
+	memcpy(&req->wb_verf, verf, sizeof(struct nfs_write_verifier));
+	nfs_request_add_commit_list(req, &cinfo);
+	ret = nfs_commit_inode(inode, FLUSH_SYNC);
+	if (ret > 0)
+		ret = 0;
+
+	nfs_free_request(req);
+out_put:
+	put_nfs_open_context(open);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(nfs_commit_file);
+
 /*
  * COMMIT call returned
  */
@@ -1748,7 +1780,8 @@ static void nfs_commit_release_pages(struct nfs_commit_data *data)
 	while (!list_empty(&data->pages)) {
 		req = nfs_list_entry(data->pages.next);
 		nfs_list_remove_request(req);
-		nfs_clear_page_commit(req->wb_page);
+		if (req->wb_page)
+			nfs_clear_page_commit(req->wb_page);
 
 		dprintk("NFS:       commit (%s/%llu %d@%lld)",
 			req->wb_context->dentry->d_sb->s_id,
-- 
2.7.2

[PATCH v3 2/3] NFS: Add COPY nfs operation

[Anna Schumaker]

From: Anna Schumaker <Anna.Schumaker@netapp.com>

This adds the copy_range file_ops function pointer used by the
sys_copy_range() function call.  This patch only implements sync copies,
so if an async copy happens we decode the stateid and ignore it.

Signed-off-by: Anna Schumaker <bjschuma@netapp.com>
--
v3:
- Update exception handling to match the rest of the v4.2 code
- Use nfs_commit_file() to send the commit through the standard
  commit path
---
 fs/nfs/nfs42.h            |   1 +
 fs/nfs/nfs42proc.c        | 105 +++++++++++++++++++++++++++++++++
 fs/nfs/nfs42xdr.c         | 146 ++++++++++++++++++++++++++++++++++++++++++++++
 fs/nfs/nfs4file.c         |  23 ++++++++
 fs/nfs/nfs4proc.c         |   1 +
 fs/nfs/nfs4xdr.c          |   1 +
 include/linux/nfs4.h      |   1 +
 include/linux/nfs_fs_sb.h |   1 +
 include/linux/nfs_xdr.h   |  26 +++++++++
 9 files changed, 305 insertions(+)

diff --git a/fs/nfs/nfs42.h b/fs/nfs/nfs42.h
index b587ccd..b6cd153 100644
--- a/fs/nfs/nfs42.h
+++ b/fs/nfs/nfs42.h
@@ -13,6 +13,7 @@
 
 /* nfs4.2proc.c */
 int nfs42_proc_allocate(struct file *, loff_t, loff_t);
+ssize_t nfs42_proc_copy(struct file *, loff_t, struct file *, loff_t, size_t);
 int nfs42_proc_deallocate(struct file *, loff_t, loff_t);
 loff_t nfs42_proc_llseek(struct file *, loff_t, int);
 int nfs42_proc_layoutstats_generic(struct nfs_server *,
diff --git a/fs/nfs/nfs42proc.c b/fs/nfs/nfs42proc.c
index dff8346..579ee20 100644
--- a/fs/nfs/nfs42proc.c
+++ b/fs/nfs/nfs42proc.c
@@ -126,6 +126,111 @@ int nfs42_proc_deallocate(struct file *filep, loff_t offset, loff_t len)
 	return err;
 }
 
+static ssize_t _nfs42_proc_copy(struct file *src, loff_t pos_src,
+				struct nfs_lock_context *src_lock,
+				struct file *dst, loff_t pos_dst,
+				struct nfs_lock_context *dst_lock,
+				size_t count)
+{
+	struct nfs42_copy_args args = {
+		.src_fh		= NFS_FH(file_inode(src)),
+		.src_pos	= pos_src,
+		.dst_fh		= NFS_FH(file_inode(dst)),
+		.dst_pos	= pos_dst,
+		.count		= count,
+	};
+	struct nfs42_copy_res res;
+	struct rpc_message msg = {
+		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_COPY],
+		.rpc_argp = &args,
+		.rpc_resp = &res,
+	};
+	struct inode *dst_inode = file_inode(dst);
+	struct nfs_server *server = NFS_SERVER(dst_inode);
+	int status;
+
+	status = nfs4_set_rw_stateid(&args.src_stateid, src_lock->open_context,
+				     src_lock, FMODE_READ);
+	if (status)
+		return status;
+
+	status = nfs4_set_rw_stateid(&args.dst_stateid, dst_lock->open_context,
+				     dst_lock, FMODE_WRITE);
+	if (status)
+		return status;
+
+	status = nfs4_call_sync(server->client, server, &msg,
+				&args.seq_args, &res.seq_res, 0);
+	if (status == -ENOTSUPP)
+		server->caps &= ~NFS_CAP_COPY;
+	if (status)
+		return status;
+
+	if (res.write_res.verifier.committed != NFS_FILE_SYNC) {
+		status = nfs_commit_file(dst, &res.write_res.verifier.verifier);
+		if (status)
+			return status;
+	}
+
+	truncate_pagecache_range(dst_inode, pos_dst,
+				 pos_dst + res.write_res.count);
+
+	return res.write_res.count;
+}
+
+ssize_t nfs42_proc_copy(struct file *src, loff_t pos_src,
+			struct file *dst, loff_t pos_dst,
+			size_t count)
+{
+	struct nfs_server *server = NFS_SERVER(file_inode(dst));
+	struct nfs_lock_context *src_lock;
+	struct nfs_lock_context *dst_lock;
+	struct nfs4_exception src_exception = { };
+	struct nfs4_exception dst_exception = { };
+	ssize_t err, err2;
+
+	if (!nfs_server_capable(file_inode(dst), NFS_CAP_COPY))
+		return -EOPNOTSUPP;
+
+	src_lock = nfs_get_lock_context(nfs_file_open_context(src));
+	if (IS_ERR(src_lock))
+		return PTR_ERR(src_lock);
+
+	src_exception.inode = file_inode(src);
+	src_exception.state = src_lock->open_context->state;
+
+	dst_lock = nfs_get_lock_context(nfs_file_open_context(dst));
+	if (IS_ERR(dst_lock)) {
+		err = PTR_ERR(dst_lock);
+		goto out_put_src_lock;
+	}
+
+	dst_exception.inode = file_inode(dst);
+	dst_exception.state = dst_lock->open_context->state;
+
+	do {
+		mutex_lock(&file_inode(dst)->i_mutex);
+		err = _nfs42_proc_copy(src, pos_src, src_lock,
+				       dst, pos_dst, dst_lock, count);
+		mutex_unlock(&file_inode(dst)->i_mutex);
+
+		if (err == -ENOTSUPP) {
+			err = -EOPNOTSUPP;
+			break;
+		}
+
+		err2 = nfs4_handle_exception(server, err, &src_exception);
+		err  = nfs4_handle_exception(server, err, &dst_exception);
+		if (!err)
+			err = err2;
+	} while (src_exception.retry || dst_exception.retry);
+
+	nfs_put_lock_context(dst_lock);
+out_put_src_lock:
+	nfs_put_lock_context(src_lock);
+	return err;
+}
+
 static loff_t _nfs42_proc_llseek(struct file *filep,
 		struct nfs_lock_context *lock, loff_t offset, int whence)
 {
diff --git a/fs/nfs/nfs42xdr.c b/fs/nfs/nfs42xdr.c
index 0ca482a..6dc6f2a 100644
--- a/fs/nfs/nfs42xdr.c
+++ b/fs/nfs/nfs42xdr.c
@@ -9,9 +9,22 @@
 #define encode_fallocate_maxsz		(encode_stateid_maxsz + \
 					 2 /* offset */ + \
 					 2 /* length */)
+#define NFS42_WRITE_RES_SIZE		(1 /* wr_callback_id size */ +\
+					 XDR_QUADLEN(NFS4_STATEID_SIZE) + \
+					 2 /* wr_count */ + \
+					 1 /* wr_committed */ + \
+					 XDR_QUADLEN(NFS4_VERIFIER_SIZE))
 #define encode_allocate_maxsz		(op_encode_hdr_maxsz + \
 					 encode_fallocate_maxsz)
 #define decode_allocate_maxsz		(op_decode_hdr_maxsz)
+#define encode_copy_maxsz		(op_encode_hdr_maxsz +          \
+					 XDR_QUADLEN(NFS4_STATEID_SIZE) + \
+					 XDR_QUADLEN(NFS4_STATEID_SIZE) + \
+					 2 + 2 + 2 + 1 + 1 + 1)
+#define decode_copy_maxsz		(op_decode_hdr_maxsz + \
+					 NFS42_WRITE_RES_SIZE + \
+					 1 /* cr_consecutive */ + \
+					 1 /* cr_synchronous */)
 #define encode_deallocate_maxsz		(op_encode_hdr_maxsz + \
 					 encode_fallocate_maxsz)
 #define decode_deallocate_maxsz		(op_decode_hdr_maxsz)
@@ -49,6 +62,16 @@
 					 decode_putfh_maxsz + \
 					 decode_allocate_maxsz + \
 					 decode_getattr_maxsz)
+#define NFS4_enc_copy_sz		(compound_encode_hdr_maxsz + \
+					 encode_putfh_maxsz + \
+					 encode_savefh_maxsz + \
+					 encode_putfh_maxsz + \
+					 encode_copy_maxsz)
+#define NFS4_dec_copy_sz		(compound_decode_hdr_maxsz + \
+					 decode_putfh_maxsz + \
+					 decode_savefh_maxsz + \
+					 decode_putfh_maxsz + \
+					 decode_copy_maxsz)
 #define NFS4_enc_deallocate_sz		(compound_encode_hdr_maxsz + \
 					 encode_putfh_maxsz + \
 					 encode_deallocate_maxsz + \
@@ -102,6 +125,23 @@ static void encode_allocate(struct xdr_stream *xdr,
 	encode_fallocate(xdr, args);
 }
 
+static void encode_copy(struct xdr_stream *xdr,
+			struct nfs42_copy_args *args,
+			struct compound_hdr *hdr)
+{
+	encode_op_hdr(xdr, OP_COPY, decode_copy_maxsz, hdr);
+	encode_nfs4_stateid(xdr, &args->src_stateid);
+	encode_nfs4_stateid(xdr, &args->dst_stateid);
+
+	encode_uint64(xdr, args->src_pos);
+	encode_uint64(xdr, args->dst_pos);
+	encode_uint64(xdr, args->count);
+
+	encode_uint32(xdr, 1); /* consecutive = true */
+	encode_uint32(xdr, 1); /* synchronous = true */
+	encode_uint32(xdr, 0); /* src server list */
+}
+
 static void encode_deallocate(struct xdr_stream *xdr,
 			      struct nfs42_falloc_args *args,
 			      struct compound_hdr *hdr)
@@ -182,6 +222,26 @@ static void nfs4_xdr_enc_allocate(struct rpc_rqst *req,
 }
 
 /*
+ * Encode COPY request
+ */
+static void nfs4_xdr_enc_copy(struct rpc_rqst *req,
+			      struct xdr_stream *xdr,
+			      struct nfs42_copy_args *args)
+{
+	struct compound_hdr hdr = {
+		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
+	};
+
+	encode_compound_hdr(xdr, req, &hdr);
+	encode_sequence(xdr, &args->seq_args, &hdr);
+	encode_putfh(xdr, args->src_fh, &hdr);
+	encode_savefh(xdr, &hdr);
+	encode_putfh(xdr, args->dst_fh, &hdr);
+	encode_copy(xdr, args, &hdr);
+	encode_nops(&hdr);
+}
+
+/*
  * Encode DEALLOCATE request
  */
 static void nfs4_xdr_enc_deallocate(struct rpc_rqst *req,
@@ -266,6 +326,62 @@ static int decode_allocate(struct xdr_stream *xdr, struct nfs42_falloc_res *res)
 	return decode_op_hdr(xdr, OP_ALLOCATE);
 }
 
+static int decode_write_response(struct xdr_stream *xdr,
+				 struct nfs42_write_res *res)
+{
+	__be32 *p;
+	int stateids;
+
+	p = xdr_inline_decode(xdr, 4 + 8 + 4);
+	if (unlikely(!p))
+		goto out_overflow;
+
+	stateids = be32_to_cpup(p++);
+	p = xdr_decode_hyper(p, &res->count);
+	res->verifier.committed = be32_to_cpup(p);
+	return decode_verifier(xdr, &res->verifier.verifier);
+
+out_overflow:
+	print_overflow_msg(__func__, xdr);
+	return -EIO;
+}
+
+static int decode_copy_requirements(struct xdr_stream *xdr,
+				    struct nfs42_copy_res *res) {
+	__be32 *p;
+
+	p = xdr_inline_decode(xdr, 4 + 4);
+	if (unlikely(!p))
+		goto out_overflow;
+
+	res->consecutive = be32_to_cpup(p++);
+	res->synchronous = be32_to_cpup(p++);
+	return 0;
+out_overflow:
+	print_overflow_msg(__func__, xdr);
+	return -EIO;
+}
+
+static int decode_copy(struct xdr_stream *xdr, struct nfs42_copy_res *res)
+{
+	int status;
+
+	status = decode_op_hdr(xdr, OP_COPY);
+	if (status == NFS4ERR_OFFLOAD_NO_REQS) {
+		status = decode_copy_requirements(xdr, res);
+		if (status)
+			return status;
+		return NFS4ERR_OFFLOAD_NO_REQS;
+	} else if (status)
+		return status;
+
+	status = decode_write_response(xdr, &res->write_res);
+	if (status)
+		return status;
+
+	return decode_copy_requirements(xdr, res);
+}
+
 static int decode_deallocate(struct xdr_stream *xdr, struct nfs42_falloc_res *res)
 {
 	return decode_op_hdr(xdr, OP_DEALLOCATE);
@@ -331,6 +447,36 @@ out:
 }
 
 /*
+ * Decode COPY response
+ */
+static int nfs4_xdr_dec_copy(struct rpc_rqst *rqstp,
+			     struct xdr_stream *xdr,
+			     struct nfs42_copy_res *res)
+{
+	struct compound_hdr hdr;
+	int status;
+
+	status = decode_compound_hdr(xdr, &hdr);
+	if (status)
+		goto out;
+	status = decode_sequence(xdr, &res->seq_res, rqstp);
+	if (status)
+		goto out;
+	status = decode_putfh(xdr);
+	if (status)
+		goto out;
+	status = decode_savefh(xdr);
+	if (status)
+		goto out;
+	status = decode_putfh(xdr);
+	if (status)
+		goto out;
+	status = decode_copy(xdr, res);
+out:
+	return status;
+}
+
+/*
  * Decode DEALLOCATE request
  */
 static int nfs4_xdr_dec_deallocate(struct rpc_rqst *rqstp,
diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c
index 57ca1c8..c2047ef 100644
--- a/fs/nfs/nfs4file.c
+++ b/fs/nfs/nfs4file.c
@@ -160,6 +160,28 @@ nfs4_file_fsync(struct file *file, loff_t start, loff_t end, int datasync)
 }
 
 #ifdef CONFIG_NFS_V4_2
+static ssize_t nfs4_copy_file_range(struct file *file_in, loff_t pos_in,
+				    struct file *file_out, loff_t pos_out,
+				    size_t count, unsigned int flags)
+{
+	struct inode *in_inode = file_inode(file_in);
+	struct inode *out_inode = file_inode(file_out);
+	int ret;
+
+	if (in_inode == out_inode)
+		return -EINVAL;
+
+	/* flush any pending writes */
+	ret = nfs_sync_inode(in_inode);
+	if (ret)
+		return ret;
+	ret = nfs_sync_inode(out_inode);
+	if (ret)
+		return ret;
+
+	return nfs42_proc_copy(file_in, pos_in, file_out, pos_out, count);
+}
+
 static loff_t nfs4_file_llseek(struct file *filep, loff_t offset, int whence)
 {
 	loff_t ret;
@@ -274,6 +296,7 @@ const struct file_operations nfs4_file_operations = {
 	.check_flags	= nfs_check_flags,
 	.setlease	= simple_nosetlease,
 #ifdef CONFIG_NFS_V4_2
+	.copy_file_range = nfs4_copy_file_range,
 	.llseek		= nfs4_file_llseek,
 	.fallocate	= nfs42_fallocate,
 	.clone_file_range = nfs42_clone_file_range,
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index c70de30..eb08640 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -8792,6 +8792,7 @@ static const struct nfs4_minor_version_ops nfs_v4_2_minor_ops = {
 		| NFS_CAP_STATEID_NFSV41
 		| NFS_CAP_ATOMIC_OPEN_V1
 		| NFS_CAP_ALLOCATE
+		| NFS_CAP_COPY
 		| NFS_CAP_DEALLOCATE
 		| NFS_CAP_SEEK
 		| NFS_CAP_LAYOUTSTATS
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index 4e44412..bc3a3f5 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -7515,6 +7515,7 @@ struct rpc_procinfo	nfs4_procedures[] = {
 	PROC(DEALLOCATE,	enc_deallocate,		dec_deallocate),
 	PROC(LAYOUTSTATS,	enc_layoutstats,	dec_layoutstats),
 	PROC(CLONE,		enc_clone,		dec_clone),
+	PROC(COPY,		enc_copy,		dec_copy),
 #endif /* CONFIG_NFS_V4_2 */
 };
 
diff --git a/include/linux/nfs4.h b/include/linux/nfs4.h
index d6f9b4e..ed14d1a 100644
--- a/include/linux/nfs4.h
+++ b/include/linux/nfs4.h
@@ -504,6 +504,7 @@ enum {
 	NFSPROC4_CLNT_DEALLOCATE,
 	NFSPROC4_CLNT_LAYOUTSTATS,
 	NFSPROC4_CLNT_CLONE,
+	NFSPROC4_CLNT_COPY,
 };
 
 /* nfs41 types */
diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h
index 7fcc13c..14a762d 100644
--- a/include/linux/nfs_fs_sb.h
+++ b/include/linux/nfs_fs_sb.h
@@ -246,5 +246,6 @@ struct nfs_server {
 #define NFS_CAP_DEALLOCATE	(1U << 21)
 #define NFS_CAP_LAYOUTSTATS	(1U << 22)
 #define NFS_CAP_CLONE		(1U << 23)
+#define NFS_CAP_COPY		(1U << 24)
 
 #endif
diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index d320906..d7adcab 100644
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -1343,6 +1343,32 @@ struct nfs42_falloc_res {
 	const struct nfs_server		*falloc_server;
 };
 
+struct nfs42_copy_args {
+	struct nfs4_sequence_args	seq_args;
+
+	struct nfs_fh			*src_fh;
+	nfs4_stateid			src_stateid;
+	u64				src_pos;
+
+	struct nfs_fh			*dst_fh;
+	nfs4_stateid			dst_stateid;
+	u64				dst_pos;
+
+	u64				count;
+};
+
+struct nfs42_write_res {
+	u64			count;
+	struct nfs_writeverf	verifier;
+};
+
+struct nfs42_copy_res {
+	struct nfs4_sequence_res	seq_res;
+	struct nfs42_write_res		write_res;
+	bool				consecutive;
+	bool				synchronous;
+};
+
 struct nfs42_seek_args {
 	struct nfs4_sequence_args	seq_args;
 
-- 
2.7.2

[PATCH v3 3/3] NFSD: Implement the COPY call

[Anna Schumaker]

From: Anna Schumaker <Anna.Schumaker@netapp.com>

I only implemented the sync version of this call, since it's the
easiest.  I can simply call vfs_copy_range() and have the vfs do the
right thing for the filesystem being exported.

Signed-off-by: Anna Schumaker <bjschuma@netapp.com>
--
v3:
- Check for copying beyond the end of the file
---
 fs/nfsd/nfs4proc.c | 98 ++++++++++++++++++++++++++++++++++++++++++++++++------
 fs/nfsd/nfs4xdr.c  | 63 +++++++++++++++++++++++++++++++++--
 fs/nfsd/vfs.c      |  6 ++++
 fs/nfsd/vfs.h      |  1 +
 fs/nfsd/xdr4.h     | 23 +++++++++++++
 5 files changed, 178 insertions(+), 13 deletions(-)

diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
index 4cba786..0a1aa2f 100644
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -1012,47 +1012,105 @@ nfsd4_write(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 }
 
 static __be32
-nfsd4_clone(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
-		struct nfsd4_clone *clone)
+nfsd4_verify_copy(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
+		  stateid_t *src_stateid, struct file **src,
+		  stateid_t *dst_stateid, struct file **dst)
 {
-	struct file *src, *dst;
 	__be32 status;
 
 	status = nfs4_preprocess_stateid_op(rqstp, cstate, &cstate->save_fh,
-					    &clone->cl_src_stateid, RD_STATE,
-					    &src, NULL);
+					    src_stateid, RD_STATE, src, NULL);
 	if (status) {
 		dprintk("NFSD: %s: couldn't process src stateid!\n", __func__);
 		goto out;
 	}
 
 	status = nfs4_preprocess_stateid_op(rqstp, cstate, &cstate->current_fh,
-					    &clone->cl_dst_stateid, WR_STATE,
-					    &dst, NULL);
+					    dst_stateid, WR_STATE, dst, NULL);
 	if (status) {
 		dprintk("NFSD: %s: couldn't process dst stateid!\n", __func__);
 		goto out_put_src;
 	}
 
 	/* fix up for NFS-specific error code */
-	if (!S_ISREG(file_inode(src)->i_mode) ||
-	    !S_ISREG(file_inode(dst)->i_mode)) {
+	if (!S_ISREG(file_inode(*src)->i_mode) ||
+	    !S_ISREG(file_inode(*dst)->i_mode)) {
 		status = nfserr_wrong_type;
 		goto out_put_dst;
 	}
 
+out:
+	return status;
+out_put_dst:
+	fput(*dst);
+out_put_src:
+	fput(*src);
+	goto out;
+}
+
+static __be32
+nfsd4_clone(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
+		struct nfsd4_clone *clone)
+{
+	struct file *src, *dst;
+	__be32 status;
+
+	status = nfsd4_verify_copy(rqstp, cstate, &clone->cl_src_stateid, &src,
+				   &clone->cl_dst_stateid, &dst);
+	if (status)
+		goto out;
+
 	status = nfsd4_clone_file_range(src, clone->cl_src_pos,
 			dst, clone->cl_dst_pos, clone->cl_count);
 
-out_put_dst:
 	fput(dst);
-out_put_src:
 	fput(src);
 out:
 	return status;
 }
 
 static __be32
+nfsd4_copy(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
+		struct nfsd4_copy *copy)
+{
+	struct file *src, *dst;
+	__be32 status;
+	ssize_t bytes;
+	loff_t max;
+
+	status = nfsd4_verify_copy(rqstp, cstate, &copy->cp_src_stateid, &src,
+				   &copy->cp_dst_stateid, &dst);
+	if (status)
+		goto out;
+
+	max = i_size_read(file_inode(src));
+	if ((copy->cp_src_pos + copy->cp_count) > max) {
+		status = nfserr_inval;
+		goto out_put;
+	}
+
+	bytes = nfsd_copy_range(src, copy->cp_src_pos, dst, copy->cp_dst_pos,
+				copy->cp_count);
+
+	if (bytes < 0)
+		status = nfserrno(bytes);
+	else {
+		copy->cp_res.wr_bytes_written = bytes;
+		copy->cp_res.wr_stable_how = NFS_UNSTABLE;
+		copy->cp_consecutive = 1;
+		copy->cp_synchronous = 1;
+		gen_boot_verifier(&copy->cp_res.wr_verifier, SVC_NET(rqstp));
+		status = nfs_ok;
+	}
+
+out_put:
+	fput(src);
+	fput(dst);
+out:
+	return status;
+}
+
+static __be32
 nfsd4_fallocate(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 		struct nfsd4_fallocate *fallocate, int flags)
 {
@@ -1966,6 +2024,18 @@ static inline u32 nfsd4_create_session_rsize(struct svc_rqst *rqstp, struct nfsd
 		op_encode_channel_attrs_maxsz) * sizeof(__be32);
 }
 
+static inline u32 nfsd4_copy_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
+{
+	return (op_encode_hdr_size +
+		1 /* wr_callback */ +
+		op_encode_stateid_maxsz /* wr_callback */ +
+		2 /* wr_count */ +
+		1 /* wr_committed */ +
+		op_encode_verifier_maxsz +
+		1 /* cr_consecutive */ +
+		1 /* cr_synchronous */) * sizeof(__be32);
+}
+
 #ifdef CONFIG_NFSD_PNFS
 /*
  * At this stage we don't really know what layout driver will handle the request,
@@ -2328,6 +2398,12 @@ static struct nfsd4_operation nfsd4_ops[] = {
 		.op_name = "OP_CLONE",
 		.op_rsize_bop = (nfsd4op_rsize)nfsd4_only_status_rsize,
 	},
+	[OP_COPY] = {
+		.op_func = (nfsd4op_func)nfsd4_copy,
+		.op_flags = OP_MODIFIES_SOMETHING | OP_CACHEME,
+		.op_name = "OP_COPY",
+		.op_rsize_bop = (nfsd4op_rsize)nfsd4_copy_rsize,
+	},
 	[OP_SEEK] = {
 		.op_func = (nfsd4op_func)nfsd4_seek,
 		.op_name = "OP_SEEK",
diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index d6ef095..2a73c7e 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -1694,6 +1694,30 @@ nfsd4_decode_clone(struct nfsd4_compoundargs *argp, struct nfsd4_clone *clone)
 }
 
 static __be32
+nfsd4_decode_copy(struct nfsd4_compoundargs *argp, struct nfsd4_copy *copy)
+{
+	DECODE_HEAD;
+	unsigned int tmp;
+
+	status = nfsd4_decode_stateid(argp, &copy->cp_src_stateid);
+	if (status)
+		return status;
+	status = nfsd4_decode_stateid(argp, &copy->cp_dst_stateid);
+	if (status)
+		return status;
+
+	READ_BUF(8 + 8 + 8 + 4 + 4 + 4);
+	p = xdr_decode_hyper(p, &copy->cp_src_pos);
+	p = xdr_decode_hyper(p, &copy->cp_dst_pos);
+	p = xdr_decode_hyper(p, &copy->cp_count);
+	copy->cp_consecutive = be32_to_cpup(p++);
+	copy->cp_synchronous = be32_to_cpup(p++);
+	tmp = be32_to_cpup(p); /* Source server list not supported */
+
+	DECODE_TAIL;
+}
+
+static __be32
 nfsd4_decode_seek(struct nfsd4_compoundargs *argp, struct nfsd4_seek *seek)
 {
 	DECODE_HEAD;
@@ -1793,7 +1817,7 @@ static nfsd4_dec nfsd4_dec_ops[] = {
 
 	/* new operations for NFSv4.2 */
 	[OP_ALLOCATE]		= (nfsd4_dec)nfsd4_decode_fallocate,
-	[OP_COPY]		= (nfsd4_dec)nfsd4_decode_notsupp,
+	[OP_COPY]		= (nfsd4_dec)nfsd4_decode_copy,
 	[OP_COPY_NOTIFY]	= (nfsd4_dec)nfsd4_decode_notsupp,
 	[OP_DEALLOCATE]		= (nfsd4_dec)nfsd4_decode_fallocate,
 	[OP_IO_ADVISE]		= (nfsd4_dec)nfsd4_decode_notsupp,
@@ -4203,6 +4227,41 @@ nfsd4_encode_layoutreturn(struct nfsd4_compoundres *resp, __be32 nfserr,
 #endif /* CONFIG_NFSD_PNFS */
 
 static __be32
+nfsd42_encode_write_res(struct nfsd4_compoundres *resp, struct nfsd42_write_res *write)
+{
+	__be32 *p;
+
+	p = xdr_reserve_space(&resp->xdr, 4 + 8 + 4 + NFS4_VERIFIER_SIZE);
+	if (!p)
+		return nfserr_resource;
+
+	*p++ = cpu_to_be32(0);
+	p = xdr_encode_hyper(p, write->wr_bytes_written);
+	*p++ = cpu_to_be32(write->wr_stable_how);
+	p = xdr_encode_opaque_fixed(p, write->wr_verifier.data,
+				    NFS4_VERIFIER_SIZE);
+	return nfs_ok;
+}
+
+static __be32
+nfsd4_encode_copy(struct nfsd4_compoundres *resp, __be32 nfserr,
+		  struct nfsd4_copy *copy)
+{
+	__be32 *p;
+
+	if (!nfserr) {
+		nfserr = nfsd42_encode_write_res(resp, &copy->cp_res);
+		if (nfserr)
+			return nfserr;
+
+		p = xdr_reserve_space(&resp->xdr, 4 + 4);
+		*p++ = cpu_to_be32(copy->cp_consecutive);
+		*p++ = cpu_to_be32(copy->cp_synchronous);
+	}
+	return nfserr;
+}
+
+static __be32
 nfsd4_encode_seek(struct nfsd4_compoundres *resp, __be32 nfserr,
 		  struct nfsd4_seek *seek)
 {
@@ -4301,7 +4360,7 @@ static nfsd4_enc nfsd4_enc_ops[] = {
 
 	/* NFSv4.2 operations */
 	[OP_ALLOCATE]		= (nfsd4_enc)nfsd4_encode_noop,
-	[OP_COPY]		= (nfsd4_enc)nfsd4_encode_noop,
+	[OP_COPY]		= (nfsd4_enc)nfsd4_encode_copy,
 	[OP_COPY_NOTIFY]	= (nfsd4_enc)nfsd4_encode_noop,
 	[OP_DEALLOCATE]		= (nfsd4_enc)nfsd4_encode_noop,
 	[OP_IO_ADVISE]		= (nfsd4_enc)nfsd4_encode_noop,
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 5d2a57e..28802a7 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -513,6 +513,12 @@ __be32 nfsd4_clone_file_range(struct file *src, u64 src_pos, struct file *dst,
 			count));
 }
 
+ssize_t nfsd_copy_range(struct file *src, u64 src_pos, struct file *dst,
+			u64 dst_pos, u64 count)
+{
+	return vfs_copy_file_range(src, src_pos, dst, dst_pos, count, 0);
+}
+
 __be32 nfsd4_vfs_fallocate(struct svc_rqst *rqstp, struct svc_fh *fhp,
 			   struct file *file, loff_t offset, loff_t len,
 			   int flags)
diff --git a/fs/nfsd/vfs.h b/fs/nfsd/vfs.h
index c11ba31..e36c497 100644
--- a/fs/nfsd/vfs.h
+++ b/fs/nfsd/vfs.h
@@ -93,6 +93,7 @@ __be32		nfsd_symlink(struct svc_rqst *, struct svc_fh *,
 				struct svc_fh *res);
 __be32		nfsd_link(struct svc_rqst *, struct svc_fh *,
 				char *, int, struct svc_fh *);
+ssize_t		nfsd_copy_range(struct file *, u64, struct file *, u64, u64);
 __be32		nfsd_rename(struct svc_rqst *,
 				struct svc_fh *, char *, int,
 				struct svc_fh *, char *, int);
diff --git a/fs/nfsd/xdr4.h b/fs/nfsd/xdr4.h
index d955481..2cad349 100644
--- a/fs/nfsd/xdr4.h
+++ b/fs/nfsd/xdr4.h
@@ -500,6 +500,28 @@ struct nfsd4_clone {
 	u64		cl_count;
 };
 
+struct nfsd42_write_res {
+	u64			wr_bytes_written;
+	u32			wr_stable_how;
+	nfs4_verifier		wr_verifier;
+};
+
+struct nfsd4_copy {
+	/* request */
+	stateid_t	cp_src_stateid;
+	stateid_t	cp_dst_stateid;
+	u64		cp_src_pos;
+	u64		cp_dst_pos;
+	u64		cp_count;
+
+	/* both */
+	bool		cp_consecutive;
+	bool		cp_synchronous;
+
+	/* response */
+	struct nfsd42_write_res	cp_res;
+};
+
 struct nfsd4_seek {
 	/* request */
 	stateid_t	seek_stateid;
@@ -565,6 +587,7 @@ struct nfsd4_op {
 		struct nfsd4_fallocate		allocate;
 		struct nfsd4_fallocate		deallocate;
 		struct nfsd4_clone		clone;
+		struct nfsd4_copy		copy;
 		struct nfsd4_seek		seek;
 	} u;
 	struct nfs4_replay *			replay;
-- 
2.7.2

Re: [PATCH v3 3/3] NFSD: Implement the COPY call

[J. Bruce Fields]

On Tue, Mar 08, 2016 at 04:55:57PM -0500, Anna Schumaker wrote:
> From: Anna Schumaker <Anna.Schumaker@netapp.com>
> 
> I only implemented the sync version of this call, since it's the
> easiest.  I can simply call vfs_copy_range() and have the vfs do the
> right thing for the filesystem being exported.
> 
> Signed-off-by: Anna Schumaker <bjschuma@netapp.com>
> --
> v3:
> - Check for copying beyond the end of the file
> ---
>  fs/nfsd/nfs4proc.c | 98 ++++++++++++++++++++++++++++++++++++++++++++++++------
>  fs/nfsd/nfs4xdr.c  | 63 +++++++++++++++++++++++++++++++++--
>  fs/nfsd/vfs.c      |  6 ++++
>  fs/nfsd/vfs.h      |  1 +
>  fs/nfsd/xdr4.h     | 23 +++++++++++++
>  5 files changed, 178 insertions(+), 13 deletions(-)
> 
> diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
> index 4cba786..0a1aa2f 100644
> --- a/fs/nfsd/nfs4proc.c
> +++ b/fs/nfsd/nfs4proc.c
> @@ -1012,47 +1012,105 @@ nfsd4_write(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
>  }
>  
>  static __be32
> -nfsd4_clone(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
> -		struct nfsd4_clone *clone)
> +nfsd4_verify_copy(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
> +		  stateid_t *src_stateid, struct file **src,
> +		  stateid_t *dst_stateid, struct file **dst)
>  {
> -	struct file *src, *dst;
>  	__be32 status;
>  
>  	status = nfs4_preprocess_stateid_op(rqstp, cstate, &cstate->save_fh,
> -					    &clone->cl_src_stateid, RD_STATE,
> -					    &src, NULL);
> +					    src_stateid, RD_STATE, src, NULL);
>  	if (status) {
>  		dprintk("NFSD: %s: couldn't process src stateid!\n", __func__);
>  		goto out;
>  	}
>  
>  	status = nfs4_preprocess_stateid_op(rqstp, cstate, &cstate->current_fh,
> -					    &clone->cl_dst_stateid, WR_STATE,
> -					    &dst, NULL);
> +					    dst_stateid, WR_STATE, dst, NULL);
>  	if (status) {
>  		dprintk("NFSD: %s: couldn't process dst stateid!\n", __func__);
>  		goto out_put_src;
>  	}
>  
>  	/* fix up for NFS-specific error code */
> -	if (!S_ISREG(file_inode(src)->i_mode) ||
> -	    !S_ISREG(file_inode(dst)->i_mode)) {
> +	if (!S_ISREG(file_inode(*src)->i_mode) ||
> +	    !S_ISREG(file_inode(*dst)->i_mode)) {
>  		status = nfserr_wrong_type;
>  		goto out_put_dst;
>  	}
>  
> +out:
> +	return status;
> +out_put_dst:
> +	fput(*dst);
> +out_put_src:
> +	fput(*src);
> +	goto out;
> +}
> +
> +static __be32
> +nfsd4_clone(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
> +		struct nfsd4_clone *clone)
> +{
> +	struct file *src, *dst;
> +	__be32 status;
> +
> +	status = nfsd4_verify_copy(rqstp, cstate, &clone->cl_src_stateid, &src,
> +				   &clone->cl_dst_stateid, &dst);
> +	if (status)
> +		goto out;
> +
>  	status = nfsd4_clone_file_range(src, clone->cl_src_pos,
>  			dst, clone->cl_dst_pos, clone->cl_count);
>  
> -out_put_dst:
>  	fput(dst);
> -out_put_src:
>  	fput(src);
>  out:
>  	return status;
>  }
>  
>  static __be32
> +nfsd4_copy(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
> +		struct nfsd4_copy *copy)
> +{
> +	struct file *src, *dst;
> +	__be32 status;
> +	ssize_t bytes;
> +	loff_t max;
> +
> +	status = nfsd4_verify_copy(rqstp, cstate, &copy->cp_src_stateid, &src,
> +				   &copy->cp_dst_stateid, &dst);
> +	if (status)
> +		goto out;
> +
> +	max = i_size_read(file_inode(src));
> +	if ((copy->cp_src_pos + copy->cp_count) > max) {
> +		status = nfserr_inval;
> +		goto out_put;
> +	}

If we care about the race between this check and the copy, then we need
some locking.  If we don't, then a comment explaining why not would be
useful here.

(Looks like this check, and the INVAL error, are both mandated by the
spec.  The behavior looks wrong to me--usually EINVAL's reserved for
things the client had to know was a problem, but here the client doesn't
necessarily know the file size.  I would have expected just success and
a short read.)

--b.

> +
> +	bytes = nfsd_copy_range(src, copy->cp_src_pos, dst, copy->cp_dst_pos,
> +				copy->cp_count);
> +
> +	if (bytes < 0)
> +		status = nfserrno(bytes);
> +	else {
> +		copy->cp_res.wr_bytes_written = bytes;
> +		copy->cp_res.wr_stable_how = NFS_UNSTABLE;
> +		copy->cp_consecutive = 1;
> +		copy->cp_synchronous = 1;
> +		gen_boot_verifier(&copy->cp_res.wr_verifier, SVC_NET(rqstp));
> +		status = nfs_ok;
> +	}
> +
> +out_put:
> +	fput(src);
> +	fput(dst);
> +out:
> +	return status;
> +}
> +
> +static __be32
>  nfsd4_fallocate(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
>  		struct nfsd4_fallocate *fallocate, int flags)
>  {
> @@ -1966,6 +2024,18 @@ static inline u32 nfsd4_create_session_rsize(struct svc_rqst *rqstp, struct nfsd
>  		op_encode_channel_attrs_maxsz) * sizeof(__be32);
>  }
>  
> +static inline u32 nfsd4_copy_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
> +{
> +	return (op_encode_hdr_size +
> +		1 /* wr_callback */ +
> +		op_encode_stateid_maxsz /* wr_callback */ +
> +		2 /* wr_count */ +
> +		1 /* wr_committed */ +
> +		op_encode_verifier_maxsz +
> +		1 /* cr_consecutive */ +
> +		1 /* cr_synchronous */) * sizeof(__be32);
> +}
> +
>  #ifdef CONFIG_NFSD_PNFS
>  /*
>   * At this stage we don't really know what layout driver will handle the request,
> @@ -2328,6 +2398,12 @@ static struct nfsd4_operation nfsd4_ops[] = {
>  		.op_name = "OP_CLONE",
>  		.op_rsize_bop = (nfsd4op_rsize)nfsd4_only_status_rsize,
>  	},
> +	[OP_COPY] = {
> +		.op_func = (nfsd4op_func)nfsd4_copy,
> +		.op_flags = OP_MODIFIES_SOMETHING | OP_CACHEME,
> +		.op_name = "OP_COPY",
> +		.op_rsize_bop = (nfsd4op_rsize)nfsd4_copy_rsize,
> +	},
>  	[OP_SEEK] = {
>  		.op_func = (nfsd4op_func)nfsd4_seek,
>  		.op_name = "OP_SEEK",
> diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
> index d6ef095..2a73c7e 100644
> --- a/fs/nfsd/nfs4xdr.c
> +++ b/fs/nfsd/nfs4xdr.c
> @@ -1694,6 +1694,30 @@ nfsd4_decode_clone(struct nfsd4_compoundargs *argp, struct nfsd4_clone *clone)
>  }
>  
>  static __be32
> +nfsd4_decode_copy(struct nfsd4_compoundargs *argp, struct nfsd4_copy *copy)
> +{
> +	DECODE_HEAD;
> +	unsigned int tmp;
> +
> +	status = nfsd4_decode_stateid(argp, &copy->cp_src_stateid);
> +	if (status)
> +		return status;
> +	status = nfsd4_decode_stateid(argp, &copy->cp_dst_stateid);
> +	if (status)
> +		return status;
> +
> +	READ_BUF(8 + 8 + 8 + 4 + 4 + 4);
> +	p = xdr_decode_hyper(p, &copy->cp_src_pos);
> +	p = xdr_decode_hyper(p, &copy->cp_dst_pos);
> +	p = xdr_decode_hyper(p, &copy->cp_count);
> +	copy->cp_consecutive = be32_to_cpup(p++);
> +	copy->cp_synchronous = be32_to_cpup(p++);
> +	tmp = be32_to_cpup(p); /* Source server list not supported */
> +
> +	DECODE_TAIL;
> +}
> +
> +static __be32
>  nfsd4_decode_seek(struct nfsd4_compoundargs *argp, struct nfsd4_seek *seek)
>  {
>  	DECODE_HEAD;
> @@ -1793,7 +1817,7 @@ static nfsd4_dec nfsd4_dec_ops[] = {
>  
>  	/* new operations for NFSv4.2 */
>  	[OP_ALLOCATE]		= (nfsd4_dec)nfsd4_decode_fallocate,
> -	[OP_COPY]		= (nfsd4_dec)nfsd4_decode_notsupp,
> +	[OP_COPY]		= (nfsd4_dec)nfsd4_decode_copy,
>  	[OP_COPY_NOTIFY]	= (nfsd4_dec)nfsd4_decode_notsupp,
>  	[OP_DEALLOCATE]		= (nfsd4_dec)nfsd4_decode_fallocate,
>  	[OP_IO_ADVISE]		= (nfsd4_dec)nfsd4_decode_notsupp,
> @@ -4203,6 +4227,41 @@ nfsd4_encode_layoutreturn(struct nfsd4_compoundres *resp, __be32 nfserr,
>  #endif /* CONFIG_NFSD_PNFS */
>  
>  static __be32
> +nfsd42_encode_write_res(struct nfsd4_compoundres *resp, struct nfsd42_write_res *write)
> +{
> +	__be32 *p;
> +
> +	p = xdr_reserve_space(&resp->xdr, 4 + 8 + 4 + NFS4_VERIFIER_SIZE);
> +	if (!p)
> +		return nfserr_resource;
> +
> +	*p++ = cpu_to_be32(0);
> +	p = xdr_encode_hyper(p, write->wr_bytes_written);
> +	*p++ = cpu_to_be32(write->wr_stable_how);
> +	p = xdr_encode_opaque_fixed(p, write->wr_verifier.data,
> +				    NFS4_VERIFIER_SIZE);
> +	return nfs_ok;
> +}
> +
> +static __be32
> +nfsd4_encode_copy(struct nfsd4_compoundres *resp, __be32 nfserr,
> +		  struct nfsd4_copy *copy)
> +{
> +	__be32 *p;
> +
> +	if (!nfserr) {
> +		nfserr = nfsd42_encode_write_res(resp, &copy->cp_res);
> +		if (nfserr)
> +			return nfserr;
> +
> +		p = xdr_reserve_space(&resp->xdr, 4 + 4);
> +		*p++ = cpu_to_be32(copy->cp_consecutive);
> +		*p++ = cpu_to_be32(copy->cp_synchronous);
> +	}
> +	return nfserr;
> +}
> +
> +static __be32
>  nfsd4_encode_seek(struct nfsd4_compoundres *resp, __be32 nfserr,
>  		  struct nfsd4_seek *seek)
>  {
> @@ -4301,7 +4360,7 @@ static nfsd4_enc nfsd4_enc_ops[] = {
>  
>  	/* NFSv4.2 operations */
>  	[OP_ALLOCATE]		= (nfsd4_enc)nfsd4_encode_noop,
> -	[OP_COPY]		= (nfsd4_enc)nfsd4_encode_noop,
> +	[OP_COPY]		= (nfsd4_enc)nfsd4_encode_copy,
>  	[OP_COPY_NOTIFY]	= (nfsd4_enc)nfsd4_encode_noop,
>  	[OP_DEALLOCATE]		= (nfsd4_enc)nfsd4_encode_noop,
>  	[OP_IO_ADVISE]		= (nfsd4_enc)nfsd4_encode_noop,
> diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
> index 5d2a57e..28802a7 100644
> --- a/fs/nfsd/vfs.c
> +++ b/fs/nfsd/vfs.c
> @@ -513,6 +513,12 @@ __be32 nfsd4_clone_file_range(struct file *src, u64 src_pos, struct file *dst,
>  			count));
>  }
>  
> +ssize_t nfsd_copy_range(struct file *src, u64 src_pos, struct file *dst,
> +			u64 dst_pos, u64 count)
> +{
> +	return vfs_copy_file_range(src, src_pos, dst, dst_pos, count, 0);
> +}
> +
>  __be32 nfsd4_vfs_fallocate(struct svc_rqst *rqstp, struct svc_fh *fhp,
>  			   struct file *file, loff_t offset, loff_t len,
>  			   int flags)
> diff --git a/fs/nfsd/vfs.h b/fs/nfsd/vfs.h
> index c11ba31..e36c497 100644
> --- a/fs/nfsd/vfs.h
> +++ b/fs/nfsd/vfs.h
> @@ -93,6 +93,7 @@ __be32		nfsd_symlink(struct svc_rqst *, struct svc_fh *,
>  				struct svc_fh *res);
>  __be32		nfsd_link(struct svc_rqst *, struct svc_fh *,
>  				char *, int, struct svc_fh *);
> +ssize_t		nfsd_copy_range(struct file *, u64, struct file *, u64, u64);
>  __be32		nfsd_rename(struct svc_rqst *,
>  				struct svc_fh *, char *, int,
>  				struct svc_fh *, char *, int);
> diff --git a/fs/nfsd/xdr4.h b/fs/nfsd/xdr4.h
> index d955481..2cad349 100644
> --- a/fs/nfsd/xdr4.h
> +++ b/fs/nfsd/xdr4.h
> @@ -500,6 +500,28 @@ struct nfsd4_clone {
>  	u64		cl_count;
>  };
>  
> +struct nfsd42_write_res {
> +	u64			wr_bytes_written;
> +	u32			wr_stable_how;
> +	nfs4_verifier		wr_verifier;
> +};
> +
> +struct nfsd4_copy {
> +	/* request */
> +	stateid_t	cp_src_stateid;
> +	stateid_t	cp_dst_stateid;
> +	u64		cp_src_pos;
> +	u64		cp_dst_pos;
> +	u64		cp_count;
> +
> +	/* both */
> +	bool		cp_consecutive;
> +	bool		cp_synchronous;
> +
> +	/* response */
> +	struct nfsd42_write_res	cp_res;
> +};
> +
>  struct nfsd4_seek {
>  	/* request */
>  	stateid_t	seek_stateid;
> @@ -565,6 +587,7 @@ struct nfsd4_op {
>  		struct nfsd4_fallocate		allocate;
>  		struct nfsd4_fallocate		deallocate;
>  		struct nfsd4_clone		clone;
> +		struct nfsd4_copy		copy;
>  		struct nfsd4_seek		seek;
>  	} u;
>  	struct nfs4_replay *			replay;
> -- 
> 2.7.2

Re: [PATCH v3 3/3] NFSD: Implement the COPY call

[J. Bruce Fields]

On Mon, Mar 14, 2016 at 05:34:26PM -0400, J. Bruce Fields wrote:
> On Tue, Mar 08, 2016 at 04:55:57PM -0500, Anna Schumaker wrote:
> > From: Anna Schumaker <Anna.Schumaker@netapp.com>
> >  static __be32
> > +nfsd4_copy(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
> > +		struct nfsd4_copy *copy)
> > +{
> > +	struct file *src, *dst;
> > +	__be32 status;
> > +	ssize_t bytes;
> > +	loff_t max;
> > +
> > +	status = nfsd4_verify_copy(rqstp, cstate, &copy->cp_src_stateid, &src,
> > +				   &copy->cp_dst_stateid, &dst);
> > +	if (status)
> > +		goto out;
> > +
> > +	max = i_size_read(file_inode(src));
> > +	if ((copy->cp_src_pos + copy->cp_count) > max) {
> > +		status = nfserr_inval;
> > +		goto out_put;
> > +	}
> 
> If we care about the race between this check and the copy, then we need
> some locking.  If we don't, then a comment explaining why not would be
> useful here.
> 
> (Looks like this check, and the INVAL error, are both mandated by the
> spec.  The behavior looks wrong to me--usually EINVAL's reserved for
> things the client had to know was a problem, but here the client doesn't
> necessarily know the file size.  I would have expected just success and
> a short read.)

Now that I look at it, that behavior's what's documented for the system
call too; from the man page:

	EINVAL Requested range extends beyond the end of the  source
	file;  or the flags argument is not 0.

Still seems like really strange behavior to me.

But if that's what we chose, then I think vfs_copy_range should be doing
that check for us.

--b.

[PATCH v3 4/3] vfs_copy_range() test program

[Anna Schumaker]

This is a simple C program that I used for calling the copy system call.
Usage:  ./nfscopy /nfs/original.txt /nfs/copy.txt
---
 nfscopy.c | 59 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 59 insertions(+)
 create mode 100644 nfscopy.c

diff --git a/nfscopy.c b/nfscopy.c
new file mode 100644
index 0000000..3417a14
--- /dev/null
+++ b/nfscopy.c
@@ -0,0 +1,59 @@
+#define _GNU_SOURCE
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/stat.h>
+#include <sys/syscall.h>
+#include <unistd.h>
+
+loff_t copy_file_range(int fd_in, loff_t *off_in, int fd_out,
+		       loff_t *off_out, size_t len, unsigned int flags)
+{
+	return syscall(__NR_copy_file_range, fd_in, off_in, fd_out,
+		       off_out, len, flags);
+}
+
+int main(int argc, char **argv)
+{
+	int fd_in, fd_out;
+	struct stat stat;
+	loff_t len, ret;
+	char buf[2];
+
+	if (argc != 3) {
+		fprintf(stderr, "Usage: %s <source> <destination>\n", argv[0]);
+		exit(EXIT_FAILURE);
+	}
+
+	fd_in = open(argv[1], O_RDONLY);
+	if (fd_in == -1) {
+		perror("open (argv[1])");
+		exit(EXIT_FAILURE);
+	}
+
+	if (fstat(fd_in, &stat) == -1) {
+		perror("fstat");
+		exit(EXIT_FAILURE);
+	}
+	len = stat.st_size;
+
+	fd_out = open(argv[2], O_CREAT|O_WRONLY|O_TRUNC, 0644);
+	if (fd_out == -1) {
+		perror("open (argv[2])");
+		exit(EXIT_FAILURE);
+	}
+
+	do {
+		ret = copy_file_range(fd_in, NULL, fd_out, NULL, len, 0);
+		if (ret == -1) {
+			perror("copy_file_range");
+			exit(EXIT_FAILURE);
+		}
+
+		len -= ret;
+	} while (len > 0);
+
+	close(fd_in);
+	close(fd_out);
+	exit(EXIT_SUCCESS);
+}
-- 
2.7.2

Re: [PATCH v3 4/3] vfs_copy_range() test program

[Christoph Hellwig]

Can you try to wire up varius corner case tests in xfstests, please?

We have 123 clone tests in the generic xfstests group, plus a lot of
btrfs and xfs specific ones.  It would be great to have at least the
most important ones ported to test copy as well.