Orangefs: kernel client part 2

Signed-off-by: Mike Marshall <hubcap@omnibond.com>

6 files changed, 3196 insertions, 0 deletions

diff --git a/fs/orangefs/acl.c b/fs/orangefs/acl.c
new file mode 100644
index 000000000000..e462b81a3ba1
--- /dev/null
+++ b/fs/orangefs/acl.c
@@ -0,0 +1,175 @@
+/*
+ * (C) 2001 Clemson University and The University of Chicago
+ *
+ * See COPYING in top-level directory.
+ */
+
+#include "protocol.h"
+#include "pvfs2-kernel.h"
+#include "pvfs2-bufmap.h"
+#include <linux/posix_acl_xattr.h>
+#include <linux/fs_struct.h>
+
+struct posix_acl *pvfs2_get_acl(struct inode *inode, int type)
+{
+	struct posix_acl *acl;
+	int ret;
+	char *key = NULL, *value = NULL;
+
+	switch (type) {
+	case ACL_TYPE_ACCESS:
+		key = PVFS2_XATTR_NAME_ACL_ACCESS;
+		break;
+	case ACL_TYPE_DEFAULT:
+		key = PVFS2_XATTR_NAME_ACL_DEFAULT;
+		break;
+	default:
+		gossip_err("pvfs2_get_acl: bogus value of type %d\n", type);
+		return ERR_PTR(-EINVAL);
+	}
+	/*
+	 * Rather than incurring a network call just to determine the exact
+	 * length of the attribute, I just allocate a max length to save on
+	 * the network call. Conceivably, we could pass NULL to
+	 * pvfs2_inode_getxattr() to probe the length of the value, but
+	 * I don't do that for now.
+	 */
+	value = kmalloc(PVFS_MAX_XATTR_VALUELEN, GFP_KERNEL);
+	if (value == NULL)
+		return ERR_PTR(-ENOMEM);
+
+	gossip_debug(GOSSIP_ACL_DEBUG,
+		     "inode %pU, key %s, type %d\n",
+		     get_khandle_from_ino(inode),
+		     key,
+		     type);
+	ret = pvfs2_inode_getxattr(inode,
+				   "",
+				   key,
+				   value,
+				   PVFS_MAX_XATTR_VALUELEN);
+	/* if the key exists, convert it to an in-memory rep */
+	if (ret > 0) {
+		acl = posix_acl_from_xattr(&init_user_ns, value, ret);
+	} else if (ret == -ENODATA || ret == -ENOSYS) {
+		acl = NULL;
+	} else {
+		gossip_err("inode %pU retrieving acl's failed with error %d\n",
+			   get_khandle_from_ino(inode),
+			   ret);
+		acl = ERR_PTR(ret);
+	}
+	/* kfree(NULL) is safe, so don't worry if value ever got used */
+	kfree(value);
+	return acl;
+}
+
+int pvfs2_set_acl(struct inode *inode, struct posix_acl *acl, int type)
+{
+	struct pvfs2_inode_s *pvfs2_inode = PVFS2_I(inode);
+	int error = 0;
+	void *value = NULL;
+	size_t size = 0;
+	const char *name = NULL;
+
+	switch (type) {
+	case ACL_TYPE_ACCESS:
+		name = PVFS2_XATTR_NAME_ACL_ACCESS;
+		if (acl) {
+			umode_t mode = inode->i_mode;
+			/*
+			 * can we represent this with the traditional file
+			 * mode permission bits?
+			 */
+			error = posix_acl_equiv_mode(acl, &mode);
+			if (error < 0) {
+				gossip_err("%s: posix_acl_equiv_mode err: %d\n",
+					   __func__,
+					   error);
+				return error;
+			}
+
+			if (inode->i_mode != mode)
+				SetModeFlag(pvfs2_inode);
+			inode->i_mode = mode;
+			mark_inode_dirty_sync(inode);
+			if (error == 0)
+				acl = NULL;
+		}
+		break;
+	case ACL_TYPE_DEFAULT:
+		name = PVFS2_XATTR_NAME_ACL_DEFAULT;
+		break;
+	default:
+		gossip_err("%s: invalid type %d!\n", __func__, type);
+		return -EINVAL;
+	}
+
+	gossip_debug(GOSSIP_ACL_DEBUG,
+		     "%s: inode %pU, key %s type %d\n",
+		     __func__, get_khandle_from_ino(inode),
+		     name,
+		     type);
+
+	if (acl) {
+		size = posix_acl_xattr_size(acl->a_count);
+		value = kmalloc(size, GFP_KERNEL);
+		if (!value)
+			return -ENOMEM;
+
+		error = posix_acl_to_xattr(&init_user_ns, acl, value, size);
+		if (error < 0)
+			goto out;
+	}
+
+	gossip_debug(GOSSIP_ACL_DEBUG,
+		     "%s: name %s, value %p, size %zd, acl %p\n",
+		     __func__, name, value, size, acl);
+	/*
+	 * Go ahead and set the extended attribute now. NOTE: Suppose acl
+	 * was NULL, then value will be NULL and size will be 0 and that
+	 * will xlate to a removexattr. However, we don't want removexattr
+	 * complain if attributes does not exist.
+	 */
+	error = pvfs2_inode_setxattr(inode, "", name, value, size, 0);
+
+out:
+	kfree(value);
+	if (!error)
+		set_cached_acl(inode, type, acl);
+	return error;
+}
+
+int pvfs2_init_acl(struct inode *inode, struct inode *dir)
+{
+	struct pvfs2_inode_s *pvfs2_inode = PVFS2_I(inode);
+	struct posix_acl *default_acl, *acl;
+	umode_t mode = inode->i_mode;
+	int error = 0;
+
+	ClearModeFlag(pvfs2_inode);
+
+	error = posix_acl_create(dir, &mode, &default_acl, &acl);
+	if (error)
+		return error;
+
+	if (default_acl) {
+		error = pvfs2_set_acl(inode, default_acl, ACL_TYPE_DEFAULT);
+		posix_acl_release(default_acl);
+	}
+
+	if (acl) {
+		if (!error)
+			error = pvfs2_set_acl(inode, acl, ACL_TYPE_ACCESS);
+		posix_acl_release(acl);
+	}
+
+	/* If mode of the inode was changed, then do a forcible ->setattr */
+	if (mode != inode->i_mode) {
+		SetModeFlag(pvfs2_inode);
+		inode->i_mode = mode;
+		pvfs2_flush_inode(inode);
+	}
+
+	return error;
+}
diff --git a/fs/orangefs/dcache.c b/fs/orangefs/dcache.c
new file mode 100644
index 000000000000..9466b179bf24
--- /dev/null
+++ b/fs/orangefs/dcache.c
@@ -0,0 +1,142 @@
+/*
+ * (C) 2001 Clemson University and The University of Chicago
+ *
+ * See COPYING in top-level directory.
+ */
+
+/*
+ *  Implementation of dentry (directory cache) functions.
+ */
+
+#include "protocol.h"
+#include "pvfs2-kernel.h"
+
+/* Returns 1 if dentry can still be trusted, else 0. */
+static int pvfs2_revalidate_lookup(struct dentry *dentry)
+{
+	struct dentry *parent_dentry = dget_parent(dentry);
+	struct inode *parent_inode = parent_dentry->d_inode;
+	struct pvfs2_inode_s *parent = PVFS2_I(parent_inode);
+	struct inode *inode = dentry->d_inode;
+	struct pvfs2_kernel_op_s *new_op;
+	int ret = 0;
+	int err = 0;
+
+	gossip_debug(GOSSIP_DCACHE_DEBUG, "%s: attempting lookup.\n", __func__);
+
+	new_op = op_alloc(PVFS2_VFS_OP_LOOKUP);
+	if (!new_op)
+		goto out_put_parent;
+
+	new_op->upcall.req.lookup.sym_follow = PVFS2_LOOKUP_LINK_NO_FOLLOW;
+	new_op->upcall.req.lookup.parent_refn = parent->refn;
+	strncpy(new_op->upcall.req.lookup.d_name,
+		dentry->d_name.name,
+		PVFS2_NAME_LEN);
+
+	gossip_debug(GOSSIP_DCACHE_DEBUG,
+		     "%s:%s:%d interrupt flag [%d]\n",
+		     __FILE__,
+		     __func__,
+		     __LINE__,
+		     get_interruptible_flag(parent_inode));
+
+	err = service_operation(new_op, "pvfs2_lookup",
+			get_interruptible_flag(parent_inode));
+	if (err)
+		goto out_drop;
+
+	if (new_op->downcall.status != 0 ||
+	    !match_handle(new_op->downcall.resp.lookup.refn.khandle, inode)) {
+		gossip_debug(GOSSIP_DCACHE_DEBUG,
+			"%s:%s:%d "
+			"lookup failure |%s| or no match |%s|.\n",
+			__FILE__,
+			__func__,
+			__LINE__,
+			new_op->downcall.status ? "true" : "false",
+			match_handle(new_op->downcall.resp.lookup.refn.khandle,
+					inode) ? "false" : "true");
+		gossip_debug(GOSSIP_DCACHE_DEBUG,
+			     "%s:%s:%d revalidate failed\n",
+			     __FILE__, __func__, __LINE__);
+		goto out_drop;
+	}
+
+	ret = 1;
+out_release_op:
+	op_release(new_op);
+out_put_parent:
+	dput(parent_dentry);
+	return ret;
+out_drop:
+	d_drop(dentry);
+	goto out_release_op;
+}
+
+/*
+ * Verify that dentry is valid.
+ *
+ * Should return 1 if dentry can still be trusted, else 0
+ */
+static int pvfs2_d_revalidate(struct dentry *dentry, unsigned int flags)
+{
+	struct inode *inode;
+	int ret = 0;
+
+	if (flags & LOOKUP_RCU)
+		return -ECHILD;
+
+	gossip_debug(GOSSIP_DCACHE_DEBUG, "%s: called on dentry %p.\n",
+		     __func__, dentry);
+
+	/* find inode from dentry */
+	if (!dentry->d_inode) {
+		gossip_debug(GOSSIP_DCACHE_DEBUG, "%s: negative dentry.\n",
+			     __func__);
+		goto invalid_exit;
+	}
+
+	gossip_debug(GOSSIP_DCACHE_DEBUG, "%s: inode valid.\n", __func__);
+	inode = dentry->d_inode;
+
+	/*
+	 * first perform a lookup to make sure that the object not only
+	 * exists, but is still in the expected place in the name space
+	 */
+	if (!is_root_handle(inode)) {
+		if (!pvfs2_revalidate_lookup(dentry))
+			goto invalid_exit;
+	} else {
+		gossip_debug(GOSSIP_DCACHE_DEBUG,
+			     "%s: root handle, lookup skipped.\n",
+			     __func__);
+	}
+
+	/* now perform getattr */
+	gossip_debug(GOSSIP_DCACHE_DEBUG,
+		     "%s: doing getattr: inode: %p, handle: %pU\n",
+		     __func__,
+		     inode,
+		     get_khandle_from_ino(inode));
+	ret = pvfs2_inode_getattr(inode, PVFS_ATTR_SYS_ALL_NOHINT);
+	gossip_debug(GOSSIP_DCACHE_DEBUG,
+		     "%s: getattr %s (ret = %d), returning %s for dentry i_count=%d\n",
+		     __func__,
+		     (ret == 0 ? "succeeded" : "failed"),
+		     ret,
+		     (ret == 0 ? "valid" : "INVALID"),
+		     atomic_read(&inode->i_count));
+	if (ret != 0)
+		goto invalid_exit;
+
+	/* dentry is valid! */
+	return 1;
+
+invalid_exit:
+	return 0;
+}
+
+const struct dentry_operations pvfs2_dentry_operations = {
+	.d_revalidate = pvfs2_d_revalidate,
+};
diff --git a/fs/orangefs/devpvfs2-req.c b/fs/orangefs/devpvfs2-req.c
new file mode 100644
index 000000000000..3e450228f3dc
--- /dev/null
+++ b/fs/orangefs/devpvfs2-req.c
@@ -0,0 +1,997 @@
+/*
+ * (C) 2001 Clemson University and The University of Chicago
+ *
+ * Changes by Acxiom Corporation to add protocol version to kernel
+ * communication, Copyright Acxiom Corporation, 2005.
+ *
+ * See COPYING in top-level directory.
+ */
+
+#include "protocol.h"
+#include "pvfs2-kernel.h"
+#include "pvfs2-dev-proto.h"
+#include "pvfs2-bufmap.h"
+
+#include <linux/debugfs.h>
+#include <linux/slab.h>
+
+/* this file implements the /dev/pvfs2-req device node */
+
+static int open_access_count;
+
+#define DUMP_DEVICE_ERROR()                                                   \
+do {                                                                          \
+	gossip_err("*****************************************************\n");\
+	gossip_err("PVFS2 Device Error:  You cannot open the device file ");  \
+	gossip_err("\n/dev/%s more than once.  Please make sure that\nthere " \
+		   "are no ", PVFS2_REQDEVICE_NAME);                          \
+	gossip_err("instances of a program using this device\ncurrently "     \
+		   "running. (You must verify this!)\n");                     \
+	gossip_err("For example, you can use the lsof program as follows:\n");\
+	gossip_err("'lsof | grep %s' (run this as root)\n",                   \
+		   PVFS2_REQDEVICE_NAME);                                     \
+	gossip_err("  open_access_count = %d\n", open_access_count);          \
+	gossip_err("*****************************************************\n");\
+} while (0)
+
+static int hash_func(__u64 tag, int table_size)
+{
+	return tag % ((unsigned int)table_size);
+}
+
+static void pvfs2_devreq_add_op(struct pvfs2_kernel_op_s *op)
+{
+	int index = hash_func(op->tag, hash_table_size);
+
+	spin_lock(&htable_ops_in_progress_lock);
+	list_add_tail(&op->list, &htable_ops_in_progress[index]);
+	spin_unlock(&htable_ops_in_progress_lock);
+}
+
+static struct pvfs2_kernel_op_s *pvfs2_devreq_remove_op(__u64 tag)
+{
+	struct pvfs2_kernel_op_s *op, *next;
+	int index;
+
+	index = hash_func(tag, hash_table_size);
+
+	spin_lock(&htable_ops_in_progress_lock);
+	list_for_each_entry_safe(op,
+				 next,
+				 &htable_ops_in_progress[index],
+				 list) {
+		if (op->tag == tag) {
+			list_del(&op->list);
+			spin_unlock(&htable_ops_in_progress_lock);
+			return op;
+		}
+	}
+
+	spin_unlock(&htable_ops_in_progress_lock);
+	return NULL;
+}
+
+static int pvfs2_devreq_open(struct inode *inode, struct file *file)
+{
+	int ret = -EINVAL;
+
+	if (!(file->f_flags & O_NONBLOCK)) {
+		gossip_err("pvfs2: device cannot be opened in blocking mode\n");
+		goto out;
+	}
+	ret = -EACCES;
+	gossip_debug(GOSSIP_DEV_DEBUG, "pvfs2-client-core: opening device\n");
+	mutex_lock(&devreq_mutex);
+
+	if (open_access_count == 0) {
+		ret = generic_file_open(inode, file);
+		if (ret == 0)
+			open_access_count++;
+	} else {
+		DUMP_DEVICE_ERROR();
+	}
+	mutex_unlock(&devreq_mutex);
+
+out:
+
+	gossip_debug(GOSSIP_DEV_DEBUG,
+		     "pvfs2-client-core: open device complete (ret = %d)\n",
+		     ret);
+	return ret;
+}
+
+static ssize_t pvfs2_devreq_read(struct file *file,
+				 char __user *buf,
+				 size_t count, loff_t *offset)
+{
+	int ret = 0;
+	ssize_t len = 0;
+	struct pvfs2_kernel_op_s *cur_op = NULL;
+	static __s32 magic = PVFS2_DEVREQ_MAGIC;
+	__s32 proto_ver = PVFS_KERNEL_PROTO_VERSION;
+
+	if (!(file->f_flags & O_NONBLOCK)) {
+		/* We do not support blocking reads/opens any more */
+		gossip_err("pvfs2: blocking reads are not supported! (pvfs2-client-core bug)\n");
+		return -EINVAL;
+	} else {
+		struct pvfs2_kernel_op_s *op = NULL, *temp = NULL;
+		/* get next op (if any) from top of list */
+		spin_lock(&pvfs2_request_list_lock);
+		list_for_each_entry_safe(op, temp, &pvfs2_request_list, list) {
+			__s32 fsid = fsid_of_op(op);
+			/*
+			 * Check if this op's fsid is known and needs
+			 * remounting
+			 */
+			if (fsid != PVFS_FS_ID_NULL &&
+			    fs_mount_pending(fsid) == 1) {
+				gossip_debug(GOSSIP_DEV_DEBUG,
+					     "Skipping op tag %llu %s\n",
+					     llu(op->tag),
+					     get_opname_string(op));
+				continue;
+			} else {
+				/*
+				 * op does not belong to any particular fsid
+				 * or already mounted.. let it through
+				 */
+				cur_op = op;
+				spin_lock(&cur_op->lock);
+				list_del(&cur_op->list);
+				cur_op->op_linger_tmp--;
+				/*
+				 * if there is a trailer, re-add it to
+				 * the request list.
+				 */
+				if (cur_op->op_linger == 2 &&
+				    cur_op->op_linger_tmp == 1) {
+					if (cur_op->upcall.trailer_size <= 0 ||
+					    cur_op->upcall.trailer_buf == NULL)
+						gossip_err("BUG:trailer_size is %ld and trailer buf is %p\n", (long)cur_op->upcall.trailer_size, cur_op->upcall.trailer_buf);
+					/* re-add it to the head of the list */
+					list_add(&cur_op->list,
+						 &pvfs2_request_list);
+				}
+				spin_unlock(&cur_op->lock);
+				break;
+			}
+		}
+		spin_unlock(&pvfs2_request_list_lock);
+	}
+
+	if (cur_op) {
+		spin_lock(&cur_op->lock);
+
+		gossip_debug(GOSSIP_DEV_DEBUG,
+			     "client-core: reading op tag %llu %s\n",
+			     llu(cur_op->tag), get_opname_string(cur_op));
+		if (op_state_in_progress(cur_op) || op_state_serviced(cur_op)) {
+			if (cur_op->op_linger == 1)
+				gossip_err("WARNING: Current op already queued...skipping\n");
+		} else if (cur_op->op_linger == 1 ||
+			   (cur_op->op_linger == 2 &&
+			    cur_op->op_linger_tmp == 0)) {
+			/*
+			 * atomically move the operation to the
+			 * htable_ops_in_progress
+			 */
+			set_op_state_inprogress(cur_op);
+			pvfs2_devreq_add_op(cur_op);
+		}
+
+		spin_unlock(&cur_op->lock);
+
+		/* 2 cases
+		 * a) OPs with no trailers
+		 * b) OPs with trailers, Stage 1
+		 * Either way push the upcall out
+		 */
+		if (cur_op->op_linger == 1 ||
+		   (cur_op->op_linger == 2 && cur_op->op_linger_tmp == 1)) {
+			len = MAX_ALIGNED_DEV_REQ_UPSIZE;
+			if ((size_t) len <= count) {
+			    ret = copy_to_user(buf,
+					       &proto_ver,
+					       sizeof(__s32));
+			    if (ret == 0) {
+				ret = copy_to_user(buf + sizeof(__s32),
+						   &magic,
+						   sizeof(__s32));
+				if (ret == 0) {
+				    ret = copy_to_user(buf+2 * sizeof(__s32),
+						       &cur_op->tag,
+						       sizeof(__u64));
+				    if (ret == 0) {
+					ret = copy_to_user(
+						buf +
+						  2 *
+						  sizeof(__s32) +
+						  sizeof(__u64),
+						&cur_op->upcall,
+						sizeof(struct pvfs2_upcall_s));
+				    }
+				}
+			    }
+
+			    if (ret) {
+				gossip_err("Failed to copy data to user space\n");
+				len = -EFAULT;
+			    }
+			} else {
+				gossip_err
+				    ("Failed to copy data to user space\n");
+				len = -EIO;
+			}
+		}
+		/* Stage 2: Push the trailer out */
+		else if (cur_op->op_linger == 2 && cur_op->op_linger_tmp == 0) {
+			len = cur_op->upcall.trailer_size;
+			if ((size_t) len <= count) {
+				ret = copy_to_user(buf,
+						   cur_op->upcall.trailer_buf,
+						   len);
+				if (ret) {
+					gossip_err("Failed to copy trailer to user space\n");
+					len = -EFAULT;
+				}
+			} else {
+				gossip_err("Read buffer for trailer is too small (%ld as opposed to %ld)\n",
+					(long)count,
+					(long)len);
+				len = -EIO;
+			}
+		} else {
+			gossip_err("cur_op: %p (op_linger %d), (op_linger_tmp %d), erroneous request list?\n",
+				cur_op,
+				cur_op->op_linger,
+				cur_op->op_linger_tmp);
+			len = 0;
+		}
+	} else if (file->f_flags & O_NONBLOCK) {
+		/*
+		 * if in non-blocking mode, return EAGAIN since no requests are
+		 * ready yet
+		 */
+		len = -EAGAIN;
+	}
+	return len;
+}
+
+/* Function for writev() callers into the device */
+static ssize_t pvfs2_devreq_writev(struct file *file,
+				   const struct iovec *iov,
+				   size_t count,
+				   loff_t *offset)
+{
+	struct pvfs2_kernel_op_s *op = NULL;
+	void *buffer = NULL;
+	void *ptr = NULL;
+	unsigned long i = 0;
+	static int max_downsize = MAX_ALIGNED_DEV_REQ_DOWNSIZE;
+	int ret = 0, num_remaining = max_downsize;
+	int notrailer_count = 4; /* num elements in iovec without trailer */
+	int payload_size = 0;
+	__s32 magic = 0;
+	__s32 proto_ver = 0;
+	__u64 tag = 0;
+	ssize_t total_returned_size = 0;
+
+	/* Either there is a trailer or there isn't */
+	if (count != notrailer_count && count != (notrailer_count + 1)) {
+		gossip_err("Error: Number of iov vectors is (%ld) and notrailer count is %d\n",
+			count,
+			notrailer_count);
+		return -EPROTO;
+	}
+	buffer = dev_req_alloc();
+	if (!buffer)
+		return -ENOMEM;
+	ptr = buffer;
+
+	for (i = 0; i < notrailer_count; i++) {
+		if (iov[i].iov_len > num_remaining) {
+			gossip_err
+			    ("writev error: Freeing buffer and returning\n");
+			dev_req_release(buffer);
+			return -EMSGSIZE;
+		}
+		ret = copy_from_user(ptr, iov[i].iov_base, iov[i].iov_len);
+		if (ret) {
+			gossip_err("Failed to copy data from user space\n");
+			dev_req_release(buffer);
+			return -EIO;
+		}
+		num_remaining -= iov[i].iov_len;
+		ptr += iov[i].iov_len;
+		payload_size += iov[i].iov_len;
+	}
+	total_returned_size = payload_size;
+
+	/* these elements are currently 8 byte aligned (8 bytes for (version +
+	 * magic) 8 bytes for tag).  If you add another element, either
+	 * make it 8 bytes big, or use get_unaligned when asigning.
+	 */
+	ptr = buffer;
+	proto_ver = *((__s32 *) ptr);
+	ptr += sizeof(__s32);
+
+	magic = *((__s32 *) ptr);
+	ptr += sizeof(__s32);
+
+	tag = *((__u64 *) ptr);
+	ptr += sizeof(__u64);
+
+	if (magic != PVFS2_DEVREQ_MAGIC) {
+		gossip_err("Error: Device magic number does not match.\n");
+		dev_req_release(buffer);
+		return -EPROTO;
+	}
+
+	/*
+	 * proto_ver = 20902 for 2.9.2
+	 */
+
+	op = pvfs2_devreq_remove_op(tag);
+	if (op) {
+		/* Increase ref count! */
+		get_op(op);
+		/* cut off magic and tag from payload size */
+		payload_size -= (2 * sizeof(__s32) + sizeof(__u64));
+		if (payload_size <= sizeof(struct pvfs2_downcall_s))
+			/* copy the passed in downcall into the op */
+			memcpy(&op->downcall,
+			       ptr,
+			       sizeof(struct pvfs2_downcall_s));
+		else
+			gossip_debug(GOSSIP_DEV_DEBUG,
+				     "writev: Ignoring %d bytes\n",
+				     payload_size);
+
+		/* Do not allocate needlessly if client-core forgets
+		 * to reset trailer size on op errors.
+		 */
+		if (op->downcall.status == 0 && op->downcall.trailer_size > 0) {
+			gossip_debug(GOSSIP_DEV_DEBUG,
+				     "writev: trailer size %ld\n",
+				     (unsigned long)op->downcall.trailer_size);
+			if (count != (notrailer_count + 1)) {
+				gossip_err("Error: trailer size (%ld) is non-zero, no trailer elements though? (%ld)\n", (unsigned long)op->downcall.trailer_size, count);
+				dev_req_release(buffer);
+				put_op(op);
+				return -EPROTO;
+			}
+			if (iov[notrailer_count].iov_len >
+			    op->downcall.trailer_size) {
+				gossip_err("writev error: trailer size (%ld) != iov_len (%ld)\n", (unsigned long)op->downcall.trailer_size, (unsigned long)iov[notrailer_count].iov_len);
+				dev_req_release(buffer);
+				put_op(op);
+				return -EMSGSIZE;
+			}
+			/* Allocate a buffer large enough to hold the
+			 * trailer bytes.
+			 */
+			op->downcall.trailer_buf =
+			    vmalloc(op->downcall.trailer_size);
+			if (op->downcall.trailer_buf != NULL) {
+				gossip_debug(GOSSIP_DEV_DEBUG, "vmalloc: %p\n",
+					     op->downcall.trailer_buf);
+				ret = copy_from_user(op->downcall.trailer_buf,
+						     iov[notrailer_count].
+						     iov_base,
+						     iov[notrailer_count].
+						     iov_len);
+				if (ret) {
+					gossip_err("Failed to copy trailer data from user space\n");
+					dev_req_release(buffer);
+					gossip_debug(GOSSIP_DEV_DEBUG,
+						     "vfree: %p\n",
+						     op->downcall.trailer_buf);
+					vfree(op->downcall.trailer_buf);
+					op->downcall.trailer_buf = NULL;
+					put_op(op);
+					return -EIO;
+				}
+			} else {
+				/* Change downcall status */
+				op->downcall.status = -ENOMEM;
+				gossip_err("writev: could not vmalloc for trailer!\n");
+			}
+		}
+
+		/* if this operation is an I/O operation and if it was
+		 * initiated on behalf of a *synchronous* VFS I/O operation,
+		 * only then we need to wait
+		 * for all data to be copied before we can return to avoid
+		 * buffer corruption and races that can pull the buffers
+		 * out from under us.
+		 *
+		 * Essentially we're synchronizing with other parts of the
+		 * vfs implicitly by not allowing the user space
+		 * application reading/writing this device to return until
+		 * the buffers are done being used.
+		 */
+		if ((op->upcall.type == PVFS2_VFS_OP_FILE_IO &&
+		     op->upcall.req.io.async_vfs_io == PVFS_VFS_SYNC_IO) ||
+		     op->upcall.type == PVFS2_VFS_OP_FILE_IOX) {
+			int timed_out = 0;
+			DECLARE_WAITQUEUE(wait_entry, current);
+
+			/* tell the vfs op waiting on a waitqueue
+			 * that this op is done
+			 */
+			spin_lock(&op->lock);
+			set_op_state_serviced(op);
+			spin_unlock(&op->lock);
+
+			add_wait_queue_exclusive(&op->io_completion_waitq,
+						 &wait_entry);
+			wake_up_interruptible(&op->waitq);
+
+			while (1) {
+				set_current_state(TASK_INTERRUPTIBLE);
+
+				spin_lock(&op->lock);
+				if (op->io_completed) {
+					spin_unlock(&op->lock);
+					break;
+				}
+				spin_unlock(&op->lock);
+
+				if (!signal_pending(current)) {
+					int timeout =
+					    MSECS_TO_JIFFIES(1000 *
+							     op_timeout_secs);
+					if (!schedule_timeout(timeout)) {
+						gossip_debug(GOSSIP_DEV_DEBUG, "*** I/O wait time is up\n");
+						timed_out = 1;
+						break;
+					}
+					continue;
+				}
+
+				gossip_debug(GOSSIP_DEV_DEBUG, "*** signal on I/O wait -- aborting\n");
+				break;
+			}
+
+			set_current_state(TASK_RUNNING);
+			remove_wait_queue(&op->io_completion_waitq,
+					  &wait_entry);
+
+			/* NOTE: for I/O operations we handle releasing the op
+			 * object except in the case of timeout.  the reason we
+			 * can't free the op in timeout cases is that the op
+			 * service logic in the vfs retries operations using
+			 * the same op ptr, thus it can't be freed.
+			 */
+			if (!timed_out)
+				op_release(op);
+		} else {
+
+			/*
+			 * tell the vfs op waiting on a waitqueue that
+			 * this op is done
+			 */
+			spin_lock(&op->lock);
+			set_op_state_serviced(op);
+			spin_unlock(&op->lock);
+			/*
+			   for every other operation (i.e. non-I/O), we need to
+			   wake up the callers for downcall completion
+			   notification
+			 */
+			wake_up_interruptible(&op->waitq);
+		}
+	} else {
+		/* ignore downcalls that we're not interested in */
+		gossip_debug(GOSSIP_DEV_DEBUG,
+			     "WARNING: No one's waiting for tag %llu\n",
+			     llu(tag));
+	}
+	dev_req_release(buffer);
+
+	return total_returned_size;
+}
+
+static ssize_t pvfs2_devreq_write_iter(struct kiocb *iocb,
+				      struct iov_iter *iter)
+{
+	return pvfs2_devreq_writev(iocb->ki_filp,
+				   iter->iov,
+				   iter->nr_segs,
+				   &iocb->ki_pos);
+}
+
+/* Returns whether any FS are still pending remounted */
+static int mark_all_pending_mounts(void)
+{
+	int unmounted = 1;
+	struct pvfs2_sb_info_s *pvfs2_sb = NULL;
+
+	spin_lock(&pvfs2_superblocks_lock);
+	list_for_each_entry(pvfs2_sb, &pvfs2_superblocks, list) {
+		/* All of these file system require a remount */
+		pvfs2_sb->mount_pending = 1;
+		unmounted = 0;
+	}
+	spin_unlock(&pvfs2_superblocks_lock);
+	return unmounted;
+}
+
+/*
+ * Determine if a given file system needs to be remounted or not
+ *  Returns -1 on error
+ *           0 if already mounted
+ *           1 if needs remount
+ */
+int fs_mount_pending(__s32 fsid)
+{
+	int mount_pending = -1;
+	struct pvfs2_sb_info_s *pvfs2_sb = NULL;
+
+	spin_lock(&pvfs2_superblocks_lock);
+	list_for_each_entry(pvfs2_sb, &pvfs2_superblocks, list) {
+		if (pvfs2_sb->fs_id == fsid) {
+			mount_pending = pvfs2_sb->mount_pending;
+			break;
+		}
+	}
+	spin_unlock(&pvfs2_superblocks_lock);
+	return mount_pending;
+}
+
+/*
+ * NOTE: gets called when the last reference to this device is dropped.
+ * Using the open_access_count variable, we enforce a reference count
+ * on this file so that it can be opened by only one process at a time.
+ * the devreq_mutex is used to make sure all i/o has completed
+ * before we call pvfs_bufmap_finalize, and similar such tricky
+ * situations
+ */
+static int pvfs2_devreq_release(struct inode *inode, struct file *file)
+{
+	int unmounted = 0;
+
+	gossip_debug(GOSSIP_DEV_DEBUG,
+		     "%s:pvfs2-client-core: exiting, closing device\n",
+		     __func__);
+
+	mutex_lock(&devreq_mutex);
+	pvfs_bufmap_finalize();
+
+	open_access_count--;
+
+	unmounted = mark_all_pending_mounts();
+	gossip_debug(GOSSIP_DEV_DEBUG, "PVFS2 Device Close: Filesystem(s) %s\n",
+		     (unmounted ? "UNMOUNTED" : "MOUNTED"));
+	mutex_unlock(&devreq_mutex);
+
+	/*
+	 * Walk through the list of ops in the request list, mark them
+	 * as purged and wake them up.
+	 */
+	purge_waiting_ops();
+	/*
+	 * Walk through the hash table of in progress operations; mark
+	 * them as purged and wake them up
+	 */
+	purge_inprogress_ops();
+	gossip_debug(GOSSIP_DEV_DEBUG,
+		     "pvfs2-client-core: device close complete\n");
+	return 0;
+}
+
+int is_daemon_in_service(void)
+{
+	int in_service;
+
+	/*
+	 * What this function does is checks if client-core is alive
+	 * based on the access count we maintain on the device.
+	 */
+	mutex_lock(&devreq_mutex);
+	in_service = open_access_count == 1 ? 0 : -EIO;
+	mutex_unlock(&devreq_mutex);
+	return in_service;
+}
+
+static inline long check_ioctl_command(unsigned int command)
+{
+	/* Check for valid ioctl codes */
+	if (_IOC_TYPE(command) != PVFS_DEV_MAGIC) {
+		gossip_err("device ioctl magic numbers don't match! Did you rebuild pvfs2-client-core/libpvfs2? [cmd %x, magic %x != %x]\n",
+			command,
+			_IOC_TYPE(command),
+			PVFS_DEV_MAGIC);
+		return -EINVAL;
+	}
+	/* and valid ioctl commands */
+	if (_IOC_NR(command) >= PVFS_DEV_MAXNR || _IOC_NR(command) <= 0) {
+		gossip_err("Invalid ioctl command number [%d >= %d]\n",
+			   _IOC_NR(command), PVFS_DEV_MAXNR);
+		return -ENOIOCTLCMD;
+	}
+	return 0;
+}
+
+static long dispatch_ioctl_command(unsigned int command, unsigned long arg)
+{
+	static __s32 magic = PVFS2_DEVREQ_MAGIC;
+	static __s32 max_up_size = MAX_ALIGNED_DEV_REQ_UPSIZE;
+	static __s32 max_down_size = MAX_ALIGNED_DEV_REQ_DOWNSIZE;
+	struct PVFS_dev_map_desc user_desc;
+	int ret = 0;
+	struct dev_mask_info_s mask_info = { 0 };
+	struct dev_mask2_info_s mask2_info = { 0, 0 };
+	int upstream_kmod = 1;
+	struct list_head *tmp = NULL;
+	struct pvfs2_sb_info_s *pvfs2_sb = NULL;
+
+	/* mtmoore: add locking here */
+
+	switch (command) {
+	case PVFS_DEV_GET_MAGIC:
+		return ((put_user(magic, (__s32 __user *) arg) == -EFAULT) ?
+			-EIO :
+			0);
+	case PVFS_DEV_GET_MAX_UPSIZE:
+		return ((put_user(max_up_size,
+				  (__s32 __user *) arg) == -EFAULT) ?
+					-EIO :
+					0);
+	case PVFS_DEV_GET_MAX_DOWNSIZE:
+		return ((put_user(max_down_size,
+				  (__s32 __user *) arg) == -EFAULT) ?
+					-EIO :
+					0);
+	case PVFS_DEV_MAP:
+		ret = copy_from_user(&user_desc,
+				     (struct PVFS_dev_map_desc __user *)
+				     arg,
+				     sizeof(struct PVFS_dev_map_desc));
+		return ret ? -EIO : pvfs_bufmap_initialize(&user_desc);
+	case PVFS_DEV_REMOUNT_ALL:
+		gossip_debug(GOSSIP_DEV_DEBUG,
+			     "pvfs2_devreq_ioctl: got PVFS_DEV_REMOUNT_ALL\n");
+
+		/*
+		 * remount all mounted pvfs2 volumes to regain the lost
+		 * dynamic mount tables (if any) -- NOTE: this is done
+		 * without keeping the superblock list locked due to the
+		 * upcall/downcall waiting.  also, the request semaphore is
+		 * used to ensure that no operations will be serviced until
+		 * all of the remounts are serviced (to avoid ops between
+		 * mounts to fail)
+		 */
+		ret = mutex_lock_interruptible(&request_mutex);
+		if (ret < 0)
+			return ret;
+		gossip_debug(GOSSIP_DEV_DEBUG,
+			     "pvfs2_devreq_ioctl: priority remount in progress\n");
+		list_for_each(tmp, &pvfs2_superblocks) {
+			pvfs2_sb =
+				list_entry(tmp, struct pvfs2_sb_info_s, list);
+			if (pvfs2_sb && (pvfs2_sb->sb)) {
+				gossip_debug(GOSSIP_DEV_DEBUG,
+					     "Remounting SB %p\n",
+					     pvfs2_sb);
+
+				ret = pvfs2_remount(pvfs2_sb->sb);
+				if (ret) {
+					gossip_debug(GOSSIP_DEV_DEBUG,
+						     "SB %p remount failed\n",
+						     pvfs2_sb);
+						break;
+				}
+			}
+		}
+		gossip_debug(GOSSIP_DEV_DEBUG,
+			     "pvfs2_devreq_ioctl: priority remount complete\n");
+		mutex_unlock(&request_mutex);
+		return ret;
+
+	case PVFS_DEV_UPSTREAM:
+		ret = copy_to_user((void __user *)arg,
+				    &upstream_kmod,
+				    sizeof(upstream_kmod));
+
+		if (ret != 0)
+			return -EIO;
+		else
+			return ret;
+
+	case PVFS_DEV_CLIENT_MASK:
+		ret = copy_from_user(&mask2_info,
+				     (void __user *)arg,
+				     sizeof(struct dev_mask2_info_s));
+
+		if (ret != 0)
+			return -EIO;
+
+		client_debug_mask.mask1 = mask2_info.mask1_value;
+		client_debug_mask.mask2 = mask2_info.mask2_value;
+
+		pr_info("%s: client debug mask has been been received "
+			":%llx: :%llx:\n",
+			__func__,
+			(unsigned long long)client_debug_mask.mask1,
+			(unsigned long long)client_debug_mask.mask2);
+
+		return ret;
+
+	case PVFS_DEV_CLIENT_STRING:
+		ret = copy_from_user(&client_debug_array_string,
+				     (void __user *)arg,
+				     PVFS2_MAX_DEBUG_STRING_LEN);
+		if (ret != 0) {
+			pr_info("%s: "
+				"PVFS_DEV_CLIENT_STRING: copy_from_user failed"
+				"\n",
+				__func__);
+			return -EIO;
+		}
+
+		pr_info("%s: client debug array string has been been received."
+			"\n",
+			__func__);
+
+		if (!help_string_initialized) {
+
+			/* Free the "we don't know yet" default string... */
+			kfree(debug_help_string);
+
+			/* build a proper debug help string */
+			if (orangefs_prepare_debugfs_help_string(0)) {
+				gossip_err("%s: "
+					   "prepare_debugfs_help_string failed"
+					   "\n",
+					   __func__);
+				return -EIO;
+			}
+
+			/* Replace the boilerplate boot-time debug-help file. */
+			debugfs_remove(help_file_dentry);
+
+			help_file_dentry =
+				debugfs_create_file(
+					ORANGEFS_KMOD_DEBUG_HELP_FILE,
+					0444,
+					debug_dir,
+					debug_help_string,
+					&debug_help_fops);
+
+			if (!help_file_dentry) {
+				gossip_err("%s: debugfs_create_file failed for"
+					   " :%s:!\n",
+					   __func__,
+					   ORANGEFS_KMOD_DEBUG_HELP_FILE);
+				return -EIO;
+			}
+		}
+
+		debug_mask_to_string(&client_debug_mask, 1);
+
+		debugfs_remove(client_debug_dentry);
+
+		pvfs2_client_debug_init();
+
+		help_string_initialized++;
+
+		return ret;
+
+	case PVFS_DEV_DEBUG:
+		ret = copy_from_user(&mask_info,
+				     (void __user *)arg,
+				     sizeof(mask_info));
+
+		if (ret != 0)
+			return -EIO;
+
+		if (mask_info.mask_type == KERNEL_MASK) {
+			if ((mask_info.mask_value == 0)
+			    && (kernel_mask_set_mod_init)) {
+				/*
+				 * the kernel debug mask was set when the
+				 * kernel module was loaded; don't override
+				 * it if the client-cor