[pnfs] [PATCH 3/3] pnfs-gfs2: initial GETDEVICE* work for pNFS/GFS2 integration

[David M. Richter]

Initial work on the get_device_iter() and get_device_info() export operations.
Tested at Connectathon.

Signed-off-by: David M. Richter <richterd at citi.umich.edu>
Signed-off-by: Frank Filz <ffilzlnx at us.ibm.com>
---
 fs/gfs2/ops_export.c |  113 ++++++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 113 insertions(+), 0 deletions(-)

diff --git a/fs/gfs2/ops_export.c b/fs/gfs2/ops_export.c
index 6a50629..5cb1bba 100644
--- a/fs/gfs2/ops_export.c
+++ b/fs/gfs2/ops_export.c
@@ -420,6 +420,117 @@ static int gfs2_layout_return(struct inode *inode, void *p)
 
 	return 0;
 }
+
+static int gfs2_get_device_iter(struct super_block *sb,
+				struct pnfs_deviter_arg *arg)
+{
+	if (arg->type != LAYOUT_NFSV4_FILES) {
+		printk("%s: ERROR: layout type isn't 'file' (type: %x)\n",
+			__func__, arg->type);
+		return 1;
+	}
+
+	if (arg->cookie == 0) {
+		arg->cookie = 1;
+		arg->verf = 1;
+		arg->devid = 1;
+	} else
+		arg->eof = 1;
+
+	return 0;
+}
+
+static int gfs2_get_device_info(struct super_block *sb,
+				struct pnfs_devinfo_arg *arg)
+{
+	int err, len, i = 0;
+	struct pnfs_filelayout_device fdev;
+	struct pnfs_filelayout_devaddr *daddr;
+	char ds_buf[XXX_PNFS_DS_LISTSZ], *bufp = ds_buf, *bufp2 = ds_buf;
+
+	if (arg->type != LAYOUT_NFSV4_FILES) {
+		printk("%s: ERROR: layout type isn't 'file' (type: %x)\n",
+			__func__, arg->type);
+		return 1;
+	}
+
+	if (arg->devid.pnfs_devid != 1) {
+		printk("%s: WARNING: didn't receive a deviceid of 1 "
+			"(got: 0x%llx)\n", __func__, arg->devid.pnfs_devid);
+		return 1;
+	}
+
+	/* XXX: no notifications yet */
+	arg->notify_types = 0;
+
+	printk("%s: DEBUG: current entire DS list is |%s|\n", __func__,
+	       pnfs_ds_list);
+	if (!*pnfs_ds_list) {
+		printk("%s: ERROR: pnfs_ds_list has no entries!\n", __func__);
+		return 1;
+	}
+	memset(ds_buf, '\0', XXX_PNFS_DS_LISTSZ);
+	memcpy(ds_buf, pnfs_ds_list, XXX_PNFS_DS_LISTSZ);
+
+	/* count the number of comma-delimited DS IPs */
+	for (fdev.fl_device_length = 1; (bufp = strchr(bufp, ',')); bufp++,
+			fdev.fl_device_length++);
+
+	len = sizeof(*fdev.fl_device_list) * fdev.fl_device_length;
+	fdev.fl_device_list = kzalloc(len, GFP_KERNEL);
+	if (!fdev.fl_device_list) {
+		printk("%s: ERROR: unable to kmalloc a device list buffer for "
+			"%d DSes.\n", __func__, i);
+		return 1;
+	}
+
+	fdev.fl_stripeindices_length = fdev.fl_device_length;
+	fdev.fl_stripeindices_list = kzalloc(sizeof(u32) * fdev.fl_stripeindices_length,
+						GFP_KERNEL);
+	if (!fdev.fl_stripeindices_list) {
+		printk("%s: ERROR: unable to kmalloc a stripeindices list "
+			"buffer for %d DSes.\n", __func__, i);
+		goto out_err;
+	}
+	for (i = 0; i < fdev.fl_stripeindices_length; i++)
+		fdev.fl_stripeindices_list[i] = i;
+
+	for (i = 0; (bufp = strsep(&bufp2, ",")) != NULL; i++) {
+		printk("%s: DEBUG: encoding DS |%s|\n", __func__, bufp);
+
+		daddr = kmalloc(sizeof(*daddr), GFP_KERNEL);
+		if (!daddr) {
+			printk("%s: ERROR: unable to kmalloc a device addr "
+				"buffer.\n", __func__);
+			goto out_err;
+		}
+
+		daddr->r_netid.data = "tcp";
+		daddr->r_netid.len = 3;
+		len = strlen(bufp);
+		daddr->r_addr.data = kzalloc(len + 4, GFP_KERNEL);
+		memcpy(daddr->r_addr.data, bufp, len);
+		memcpy(daddr->r_addr.data + len, ".8.1", 4);
+		daddr->r_addr.len = len + 4;
+
+		fdev.fl_device_list[i].fl_multipath_length = 1;
+		fdev.fl_device_list[i].fl_multipath_list = daddr;
+	}
+
+	/* have nfsd encode the device info */
+	err = arg->func(&arg->xdr, &fdev);
+
+out_free:
+	for (i = 0; i < fdev.fl_device_length; i++)
+		kfree(fdev.fl_device_list[i].fl_multipath_list);
+	kfree(fdev.fl_device_list);
+	kfree(fdev.fl_stripeindices_list);
+	return err;
+out_err:
+	err = 1;
+	goto out_free;
+}
+
 #endif /* CONFIG_PNFSD */
 
 const struct export_operations gfs2_export_ops = {
@@ -433,6 +544,8 @@ const struct export_operations gfs2_export_ops = {
 	.layout_get = gfs2_layout_get,
 	.layout_commit = gfs2_layout_commit,
 	.layout_return = gfs2_layout_return,
+	.get_device_iter = gfs2_get_device_iter,
+	.get_device_info = gfs2_get_device_info,
 #endif /* CONFIG_PNFSD */
 };
 
-- 
1.5.3