1 files changed, 469 insertions, 0 deletions
diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c
new file mode 100644
index 0000000000..02788c3c85
--- /dev/null
+++ b/fs/nfs/nfs4file.c
@@ -0,0 +1,469 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  linux/fs/nfs/file.c
+ *
+ *  Copyright (C) 1992  Rick Sladkey
+ */
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/falloc.h>
+#include <linux/mount.h>
+#include <linux/nfs_fs.h>
+#include <linux/nfs_ssc.h>
+#include "delegation.h"
+#include "internal.h"
+#include "iostat.h"
+#include "fscache.h"
+#include "pnfs.h"
+
+#include "nfstrace.h"
+
+#ifdef CONFIG_NFS_V4_2
+#include "nfs42.h"
+#endif
+
+#define NFSDBG_FACILITY		NFSDBG_FILE
+
+static int
+nfs4_file_open(struct inode *inode, struct file *filp)
+{
+	struct nfs_open_context *ctx;
+	struct dentry *dentry = file_dentry(filp);
+	struct dentry *parent = NULL;
+	struct inode *dir;
+	unsigned openflags = filp->f_flags;
+	struct iattr attr;
+	int err;
+
+	/*
+	 * If no cached dentry exists or if it's negative, NFSv4 handled the
+	 * opens in ->lookup() or ->create().
+	 *
+	 * We only get this far for a cached positive dentry.  We skipped
+	 * revalidation, so handle it here by dropping the dentry and returning
+	 * -EOPENSTALE.  The VFS will retry the lookup/create/open.
+	 */
+
+	dprintk("NFS: open file(%pd2)\n", dentry);
+
+	err = nfs_check_flags(openflags);
+	if (err)
+		return err;
+
+	/* We can't create new files here */
+	openflags &= ~(O_CREAT|O_EXCL);
+
+	parent = dget_parent(dentry);
+	dir = d_inode(parent);
+
+	ctx = alloc_nfs_open_context(file_dentry(filp),
+				     flags_to_mode(openflags), filp);
+	err = PTR_ERR(ctx);
+	if (IS_ERR(ctx))
+		goto out;
+
+	attr.ia_valid = ATTR_OPEN;
+	if (openflags & O_TRUNC) {
+		attr.ia_valid |= ATTR_SIZE;
+		attr.ia_size = 0;
+		filemap_write_and_wait(inode->i_mapping);
+	}
+
+	inode = NFS_PROTO(dir)->open_context(dir, ctx, openflags, &attr, NULL);
+	if (IS_ERR(inode)) {
+		err = PTR_ERR(inode);
+		switch (err) {
+		default:
+			goto out_put_ctx;
+		case -ENOENT:
+		case -ESTALE:
+		case -EISDIR:
+		case -ENOTDIR:
+		case -ELOOP:
+			goto out_drop;
+		}
+	}
+	if (inode != d_inode(dentry))
+		goto out_drop;
+
+	nfs_file_set_open_context(filp, ctx);
+	nfs_fscache_open_file(inode, filp);
+	err = 0;
+	filp->f_mode |= FMODE_CAN_ODIRECT;
+
+out_put_ctx:
+	put_nfs_open_context(ctx);
+out:
+	dput(parent);
+	return err;
+
+out_drop:
+	d_drop(dentry);
+	err = -EOPENSTALE;
+	goto out_put_ctx;
+}
+
+/*
+ * Flush all dirty pages, and check for write errors.
+ */
+static int
+nfs4_file_flush(struct file *file, fl_owner_t id)
+{
+	struct inode	*inode = file_inode(file);
+	errseq_t since;
+
+	dprintk("NFS: flush(%pD2)\n", file);
+
+	nfs_inc_stats(inode, NFSIOS_VFSFLUSH);
+	if ((file->f_mode & FMODE_WRITE) == 0)
+		return 0;
+
+	/*
+	 * If we're holding a write delegation, then check if we're required
+	 * to flush the i/o on close. If not, then just start the i/o now.
+	 */
+	if (!nfs4_delegation_flush_on_close(inode))
+		return filemap_fdatawrite(file->f_mapping);
+
+	/* Flush writes to the server and return any errors */
+	since = filemap_sample_wb_err(file->f_mapping);
+	nfs_wb_all(inode);
+	return filemap_check_wb_err(file->f_mapping, since);
+}
+
+#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 nfs42_copy_notify_res *cn_resp = NULL;
+	struct nl4_server *nss = NULL;
+	nfs4_stateid *cnrs = NULL;
+	ssize_t ret;
+	bool sync = false;
+
+	/* Only offload copy if superblock is the same */
+	if (file_in->f_op != &nfs4_file_operations)
+		return -EXDEV;
+	if (!nfs_server_capable(file_inode(file_out), NFS_CAP_COPY) ||
+	    !nfs_server_capable(file_inode(file_in), NFS_CAP_COPY))
+		return -EOPNOTSUPP;
+	if (file_inode(file_in) == file_inode(file_out))
+		return -EOPNOTSUPP;
+	/* if the copy size if smaller than 2 RPC payloads, make it
+	 * synchronous
+	 */
+	if (count <= 2 * NFS_SERVER(file_inode(file_in))->rsize)
+		sync = true;
+retry:
+	if (!nfs42_files_from_same_server(file_in, file_out)) {
+		/*
+		 * for inter copy, if copy size is too small
+		 * then fallback to generic copy.
+		 */
+		if (sync)
+			return -EOPNOTSUPP;
+		cn_resp = kzalloc(sizeof(struct nfs42_copy_notify_res),
+				  GFP_KERNEL);
+		if (unlikely(cn_resp == NULL))
+			return -ENOMEM;
+
+		ret = nfs42_proc_copy_notify(file_in, file_out, cn_resp);
+		if (ret) {
+			ret = -EOPNOTSUPP;
+			goto out;
+		}
+		nss = &cn_resp->cnr_src;
+		cnrs = &cn_resp->cnr_stateid;
+	}
+	ret = nfs42_proc_copy(file_in, pos_in, file_out, pos_out, count,
+				nss, cnrs, sync);
+out:
+	kfree(cn_resp);
+
+	if (ret == -EAGAIN)
+		goto retry;
+	return ret;
+}
+
+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)
+{
+	ssize_t ret;
+
+	ret = __nfs4_copy_file_range(file_in, pos_in, file_out, pos_out, count,
+				     flags);
+	if (ret == -EOPNOTSUPP || ret == -EXDEV)
+		ret = generic_copy_file_range(file_in, pos_in, file_out,
+					      pos_out, count, flags);
+	return ret;
+}
+
+static loff_t nfs4_file_llseek(struct file *filep, loff_t offset, int whence)
+{
+	loff_t ret;
+
+	switch (whence) {
+	case SEEK_HOLE:
+	case SEEK_DATA:
+		ret = nfs42_proc_llseek(filep, offset, whence);
+		if (ret != -EOPNOTSUPP)
+			return ret;
+		fallthrough;
+	default:
+		return nfs_file_llseek(filep, offset, whence);
+	}
+}
+
+static long nfs42_fallocate(struct file *filep, int mode, loff_t offset, loff_t len)
+{
+	struct inode *inode = file_inode(filep);
+	long ret;
+
+	if (!S_ISREG(inode->i_mode))
+		return -EOPNOTSUPP;
+
+	if ((mode != 0) && (mode != (FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE)))
+		return -EOPNOTSUPP;
+
+	ret = inode_newsize_ok(inode, offset + len);
+	if (ret < 0)
+		return ret;
+
+	if (mode & FALLOC_FL_PUNCH_HOLE)
+		return nfs42_proc_deallocate(filep, offset, len);
+	return nfs42_proc_allocate(filep, offset, len);
+}
+
+static loff_t nfs42_remap_file_range(struct file *src_file, loff_t src_off,
+		struct file *dst_file, loff_t dst_off, loff_t count,
+		unsigned int remap_flags)
+{
+	struct inode *dst_inode = file_inode(dst_file);
+	struct nfs_server *server = NFS_SERVER(dst_inode);
+	struct inode *src_inode = file_inode(src_file);
+	unsigned int bs = server->clone_blksize;
+	bool same_inode = false;
+	int ret;
+
+	/* NFS does not support deduplication. */
+	if (remap_flags & REMAP_FILE_DEDUP)
+		return -EOPNOTSUPP;
+
+	if (remap_flags & ~REMAP_FILE_ADVISORY)
+		return -EINVAL;
+
+	if (IS_SWAPFILE(dst_inode) || IS_SWAPFILE(src_inode))
+		return -ETXTBSY;
+
+	/* check alignment w.r.t. clone_blksize */
+	ret = -EINVAL;
+	if (bs) {
+		if (!IS_ALIGNED(src_off, bs) || !IS_ALIGNED(dst_off, bs))
+			goto out;
+		if (!IS_ALIGNED(count, bs) && i_size_read(src_inode) != (src_off + count))
+			goto out;
+	}
+
+	if (src_inode == dst_inode)
+		same_inode = true;
+
+	/* XXX: do we lock at all? what if server needs CB_RECALL_LAYOUT? */
+	if (same_inode) {
+		inode_lock(src_inode);
+	} else if (dst_inode < src_inode) {
+		inode_lock_nested(dst_inode, I_MUTEX_PARENT);
+		inode_lock_nested(src_inode, I_MUTEX_CHILD);
+	} else {
+		inode_lock_nested(src_inode, I_MUTEX_PARENT);
+		inode_lock_nested(dst_inode, I_MUTEX_CHILD);
+	}
+
+	/* flush all pending writes on both src and dst so that server
+	 * has the latest data */
+	ret = nfs_sync_inode(src_inode);
+	if (ret)
+		goto out_unlock;
+	ret = nfs_sync_inode(dst_inode);
+	if (ret)
+		goto out_unlock;
+
+	ret = nfs42_proc_clone(src_file, dst_file, src_off, dst_off, count);
+
+	/* truncate inode page cache of the dst range so that future reads can fetch
+	 * new data from server */
+	if (!ret)
+		truncate_inode_pages_range(&dst_inode->i_data, dst_off, dst_off + count - 1);
+
+out_unlock:
+	if (same_inode) {
+		inode_unlock(src_inode);
+	} else if (dst_inode < src_inode) {
+		inode_unlock(src_inode);
+		inode_unlock(dst_inode);
+	} else {
+		inode_unlock(dst_inode);
+		inode_unlock(src_inode);
+	}
+out:
+	return ret < 0 ? ret : count;
+}
+
+static int read_name_gen = 1;
+#define SSC_READ_NAME_BODY "ssc_read_%d"
+
+static struct file *__nfs42_ssc_open(struct vfsmount *ss_mnt,
+		struct nfs_fh *src_fh, nfs4_stateid *stateid)
+{
+	struct nfs_fattr *fattr = nfs_alloc_fattr();
+	struct file *filep, *res;
+	struct nfs_server *server;
+	struct inode *r_ino = NULL;
+	struct nfs_open_context *ctx;
+	struct nfs4_state_owner *sp;
+	char *read_name = NULL;
+	int len, status = 0;
+
+	server = NFS_SB(ss_mnt->mnt_sb);
+
+	if (!fattr)
+		return ERR_PTR(-ENOMEM);
+
+	status = nfs4_proc_getattr(server, src_fh, fattr, NULL);
+	if (status < 0) {
+		res = ERR_PTR(status);
+		goto out;
+	}
+
+	if (!S_ISREG(fattr->mode)) {
+		res = ERR_PTR(-EBADF);
+		goto out;
+	}
+
+	res = ERR_PTR(-ENOMEM);
+	len = strlen(SSC_READ_NAME_BODY) + 16;
+	read_name = kzalloc(len, GFP_KERNEL);
+	if (read_name == NULL)
+		goto out;
+	snprintf(read_name, len, SSC_READ_NAME_BODY, read_name_gen++);
+
+	r_ino = nfs_fhget(ss_mnt->mnt_sb, src_fh, fattr);
+	if (IS_ERR(r_ino)) {
+		res = ERR_CAST(r_ino);
+		goto out_free_name;
+	}
+
+	filep = alloc_file_pseudo(r_ino, ss_mnt, read_name, O_RDONLY,
+				     r_ino->i_fop);
+	if (IS_ERR(filep)) {
+		res = ERR_CAST(filep);
+		iput(r_ino);
+		goto out_free_name;
+	}
+
+	ctx = alloc_nfs_open_context(filep->f_path.dentry,
+				     flags_to_mode(filep->f_flags), filep);
+	if (IS_ERR(ctx)) {
+		res = ERR_CAST(ctx);
+		goto out_filep;
+	}
+
+	res = ERR_PTR(-EINVAL);
+	sp = nfs4_get_state_owner(server, ctx->cred, GFP_KERNEL);
+	if (sp == NULL)
+		goto out_ctx;
+
+	ctx->state = nfs4_get_open_state(r_ino, sp);
+	if (ctx->state == NULL)
+		goto out_stateowner;
+
+	set_bit(NFS_SRV_SSC_COPY_STATE, &ctx->state->flags);
+	memcpy(&ctx->state->open_stateid.other, &stateid->other,
+	       NFS4_STATEID_OTHER_SIZE);
+	update_open_stateid(ctx->state, stateid, NULL, filep->f_mode);
+	set_bit(NFS_OPEN_STATE, &ctx->state->flags);
+
+	nfs_file_set_open_context(filep, ctx);
+	put_nfs_open_context(ctx);
+
+	file_ra_state_init(&filep->f_ra, filep->f_mapping->host->i_mapping);
+	res = filep;
+out_free_name:
+	kfree(read_name);
+out:
+	nfs_free_fattr(fattr);
+	return res;
+out_stateowner:
+	nfs4_put_state_owner(sp);
+out_ctx:
+	put_nfs_open_context(ctx);
+out_filep:
+	fput(filep);
+	goto out_free_name;
+}
+
+static void __nfs42_ssc_close(struct file *filep)
+{
+	struct nfs_open_context *ctx = nfs_file_open_context(filep);
+
+	ctx->state->flags = 0;
+}
+
+static const struct nfs4_ssc_client_ops nfs4_ssc_clnt_ops_tbl = {
+	.sco_open = __nfs42_ssc_open,
+	.sco_close = __nfs42_ssc_close,
+};
+
+/**
+ * nfs42_ssc_register_ops - Wrapper to register NFS_V4 ops in nfs_common
+ *
+ * Return values:
+ *   None
+ */
+void nfs42_ssc_register_ops(void)
+{
+	nfs42_ssc_register(&nfs4_ssc_clnt_ops_tbl);
+}
+
+/**
+ * nfs42_ssc_unregister_ops - wrapper to un-register NFS_V4 ops in nfs_common
+ *
+ * Return values:
+ *   None.
+ */
+void nfs42_ssc_unregister_ops(void)
+{
+	nfs42_ssc_unregister(&nfs4_ssc_clnt_ops_tbl);
+}
+#endif /* CONFIG_NFS_V4_2 */
+
+static int nfs4_setlease(struct file *file, int arg, struct file_lock **lease,
+			 void **priv)
+{
+	return nfs4_proc_setlease(file, arg, lease, priv);
+}
+
+const struct file_operations nfs4_file_operations = {
+	.read_iter	= nfs_file_read,
+	.write_iter	= nfs_file_write,
+	.mmap		= nfs_file_mmap,
+	.open		= nfs4_file_open,
+	.flush		= nfs4_file_flush,
+	.release	= nfs_file_release,
+	.fsync		= nfs_file_fsync,
+	.lock		= nfs_lock,
+	.flock		= nfs_flock,
+	.splice_read	= nfs_file_splice_read,
+	.splice_write	= iter_file_splice_write,
+	.check_flags	= nfs_check_flags,
+	.setlease	= nfs4_setlease,
+#ifdef CONFIG_NFS_V4_2
+	.copy_file_range = nfs4_copy_file_range,
+	.llseek		= nfs4_file_llseek,
+	.fallocate	= nfs42_fallocate,
+	.remap_file_range = nfs42_remap_file_range,
+#else
+	.llseek		= nfs_file_llseek,
+#endif
+};