[pnfs] [PATCH 06/28] pnfsblock: scan scsi devices
Fred Isaman
iisaman at citi.umich.edu
Tue Mar 11 15:31:47 EDT 2008
Scan scsi devices available to map against future GETDEVICEINFO output.
Signed-off-by: Fred Isaman <iisaman at citi.umich.edu>
---
fs/nfs/blocklayout/Makefile | 2 +-
fs/nfs/blocklayout/blocklayout.c | 13 ++-
fs/nfs/blocklayout/blocklayout.h | 51 ++++++++
fs/nfs/blocklayout/blocklayoutdev.c | 220 +++++++++++++++++++++++++++++++++++
4 files changed, 282 insertions(+), 4 deletions(-)
create mode 100644 fs/nfs/blocklayout/blocklayout.h
create mode 100644 fs/nfs/blocklayout/blocklayoutdev.c
diff --git a/fs/nfs/blocklayout/Makefile b/fs/nfs/blocklayout/Makefile
index 6bf49cd..36d959f 100644
--- a/fs/nfs/blocklayout/Makefile
+++ b/fs/nfs/blocklayout/Makefile
@@ -2,4 +2,4 @@
# Makefile for the pNFS block layout driver kernel module
#
obj-$(CONFIG_PNFS_BLOCK) += blocklayoutdriver.o
-blocklayoutdriver-objs := blocklayout.o
+blocklayoutdriver-objs := blocklayout.o blocklayoutdev.o
diff --git a/fs/nfs/blocklayout/blocklayout.c b/fs/nfs/blocklayout/blocklayout.c
index e4e64fc..86a1fe4 100644
--- a/fs/nfs/blocklayout/blocklayout.c
+++ b/fs/nfs/blocklayout/blocklayout.c
@@ -32,9 +32,7 @@
#include <linux/module.h>
#include <linux/init.h>
-#include <linux/nfs_fs.h>
-#include <linux/pnfs_xdr.h> /* Needed by nfs4_pnfs.h */
-#include <linux/nfs4_pnfs.h>
+#include "blocklayout.h"
#define NFSDBG_FACILITY NFSDBG_BLOCKLAYOUT
@@ -135,10 +133,19 @@ bl_cleanup_layoutcommit(struct pnfs_layout_type *layoutid,
dprintk("%s enter\n", __func__);
}
+/*
+ * This is just a STUB to check the scsi scanning code
+ */
static struct pnfs_mount_type *
bl_initialize_mountpoint(struct super_block *sb, struct nfs_fh *fh)
{
+ LIST_HEAD(scsi_disklist);
+
dprintk("%s enter\n", __func__);
+
+ nfs4_blk_create_scsi_disk_list(&scsi_disklist);
+ nfs4_blk_destroy_disk_list(&scsi_disklist);
+
return NULL;
}
diff --git a/fs/nfs/blocklayout/blocklayout.h b/fs/nfs/blocklayout/blocklayout.h
new file mode 100644
index 0000000..2fb2200
--- /dev/null
+++ b/fs/nfs/blocklayout/blocklayout.h
@@ -0,0 +1,51 @@
+/*
+ * linux/fs/nfs/blocklayout/blocklayout.h
+ *
+ * Module for the NFSv4.1 pNFS block layout driver.
+ *
+ * Copyright (c) 2006 The Regents of the University of Michigan.
+ * All rights reserved.
+ *
+ * Andy Adamson <andros at citi.umich.edu>
+ * Fred Isaman <iisaman at umich.edu>
+ *
+ * permission is granted to use, copy, create derivative works and
+ * redistribute this software and such derivative works for any purpose,
+ * so long as the name of the university of michigan is not used in
+ * any advertising or publicity pertaining to the use or distribution
+ * of this software without specific, written prior authorization. if
+ * the above copyright notice or any other identification of the
+ * university of michigan is included in any copy of any portion of
+ * this software, then the disclaimer below must also be included.
+ *
+ * this software is provided as is, without representation from the
+ * university of michigan as to its fitness for any purpose, and without
+ * warranty by the university of michigan of any kind, either express
+ * or implied, including without limitation the implied warranties of
+ * merchantability and fitness for a particular purpose. the regents
+ * of the university of michigan shall not be liable for any damages,
+ * including special, indirect, incidental, or consequential damages,
+ * with respect to any claim arising out or in connection with the use
+ * of the software, even if it has been or is hereafter advised of the
+ * possibility of such damages.
+ */
+#ifndef FS_NFS_NFS4BLOCKLAYOUT_H
+#define FS_NFS_NFS4BLOCKLAYOUT_H
+
+#include <linux/nfs_fs.h>
+#include <linux/pnfs_xdr.h> /* Needed by nfs4_pnfs.h */
+#include <linux/nfs4_pnfs.h>
+
+extern struct class shost_class; /* exported from drivers/scsi/hosts.c */
+
+/* holds visible disks that can be matched against VOLUME_SIMPLE signatures */
+struct visible_block_device {
+ struct list_head vi_node;
+ struct block_device *vi_bdev;
+ int vi_mapped;
+};
+
+int nfs4_blk_create_scsi_disk_list(struct list_head *);
+void nfs4_blk_destroy_disk_list(struct list_head *);
+
+#endif /* FS_NFS_NFS4BLOCKLAYOUT_H */
diff --git a/fs/nfs/blocklayout/blocklayoutdev.c b/fs/nfs/blocklayout/blocklayoutdev.c
new file mode 100644
index 0000000..d4eff35
--- /dev/null
+++ b/fs/nfs/blocklayout/blocklayoutdev.c
@@ -0,0 +1,220 @@
+/*
+ * linux/fs/nfs/blocklayout/blocklayoutdev.c
+ *
+ * Device operations for the pnfs nfs4 file layout driver.
+ *
+ * Copyright (c) 2006 The Regents of the University of Michigan.
+ * All rights reserved.
+ *
+ * Andy Adamson <andros at citi.umich.edu>
+ * Fred Isaman <iisaman at umich.edu>
+ *
+ * permission is granted to use, copy, create derivative works and
+ * redistribute this software and such derivative works for any purpose,
+ * so long as the name of the university of michigan is not used in
+ * any advertising or publicity pertaining to the use or distribution
+ * of this software without specific, written prior authorization. if
+ * the above copyright notice or any other identification of the
+ * university of michigan is included in any copy of any portion of
+ * this software, then the disclaimer below must also be included.
+ *
+ * this software is provided as is, without representation from the
+ * university of michigan as to its fitness for any purpose, and without
+ * warranty by the university of michigan of any kind, either express
+ * or implied, including without limitation the implied warranties of
+ * merchantability and fitness for a particular purpose. the regents
+ * of the university of michigan shall not be liable for any damages,
+ * including special, indirect, incidental, or consequential damages,
+ * with respect to any claim arising out or in connection with the use
+ * of the software, even if it has been or is hereafter advised of the
+ * possibility of such damages.
+ */
+#include <linux/module.h>
+#include <linux/buffer_head.h> /* __bread */
+
+#include <scsi/scsi.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_host.h>
+
+#include "blocklayout.h"
+
+#define NFSDBG_FACILITY NFSDBG_BLOCKLAYOUT
+
+#define MAX_VOLS 256 /* Maximum number of SCSI disks. Totally arbitrary */
+
+uint32_t *blk_overflow(uint32_t *p, uint32_t *end, size_t nbytes)
+{
+ uint32_t *q = p + XDR_QUADLEN(nbytes);
+ if (unlikely(q > end || q < p))
+ return NULL;
+ return p;
+}
+EXPORT_SYMBOL(blk_overflow);
+
+/* Open a block_device by device number. */
+static struct block_device *nfs4_blkdev_get(dev_t dev)
+{
+ struct block_device *bd;
+
+ dprintk("%s enter\n", __func__);
+ bd = open_by_devnum(dev, FMODE_READ);
+ if (IS_ERR(bd))
+ goto fail;
+ return bd;
+fail:
+ dprintk("%s failed to open device : %ld\n",
+ __func__, PTR_ERR(bd));
+ return NULL;
+}
+
+/*
+ * Release the block device
+ */
+static int nfs4_blkdev_put(struct block_device *bdev)
+{
+ dprintk("%s for device %d:%d\n", __func__, MAJOR(bdev->bd_dev),
+ MINOR(bdev->bd_dev));
+ bd_release(bdev);
+ return blkdev_put(bdev);
+}
+
+/* Add a visible, claimed (by us!) scsi disk to the device list */
+static int alloc_add_disk(struct block_device *blk_dev, struct list_head *dlist)
+{
+ struct visible_block_device *vis_dev;
+
+ dprintk("%s enter\n", __func__);
+ vis_dev = kmalloc(sizeof(struct visible_block_device), GFP_KERNEL);
+ if (!vis_dev) {
+ dprintk("%s nfs4_get_sig failed\n", __func__);
+ return -ENOMEM;
+ }
+ vis_dev->vi_bdev = blk_dev;
+ vis_dev->vi_mapped = 0;
+ list_add(&vis_dev->vi_node, dlist);
+ return 0;
+}
+
+/* Walk the list of scsi_devices. Add disks that can be opened and claimed
+ * to the device list
+ */
+static int
+nfs4_blk_add_scsi_disk(struct Scsi_Host *shost,
+ int index, struct list_head *dlist)
+{
+ static char *claim_ptr = "I belong to pnfs block driver";
+ struct block_device *bdev;
+ struct gendisk *gd;
+ struct scsi_device *sdev;
+ unsigned int major, minor, ret = 0;
+ dev_t dev;
+
+ dprintk("%s enter \n", __func__);
+ if (index >= MAX_VOLS) {
+ dprintk("%s MAX_VOLS hit\n", __func__);
+ return -ENOSPC;
+ }
+ dprintk("%s 1 \n", __func__);
+ index--;
+ shost_for_each_device(sdev, shost) {
+ dprintk("%s 2\n", __func__);
+ /* Need to do this check before bumping index */
+ if (sdev->type != TYPE_DISK)
+ continue;
+ dprintk("%s 3 index %d \n", __func__, index);
+ if (++index >= MAX_VOLS) {
+ scsi_device_put(sdev);
+ break;
+ }
+ major = (!(index >> 4) ? SCSI_DISK0_MAJOR :
+ SCSI_DISK1_MAJOR-1 + (index >> 4));
+ minor = ((index << 4) & 255);
+
+ dprintk("%s SCSI device %d:%d \n", __func__, major, minor);
+
+ dev = MKDEV(major, minor);
+ bdev = nfs4_blkdev_get(dev);
+ if (!bdev) {
+ dprintk("%s: failed to open device %d:%d\n",
+ __func__, major, minor);
+ continue;
+ }
+ gd = bdev->bd_disk;
+
+ dprintk("%s 4\n", __func__);
+
+ if (bd_claim(bdev, claim_ptr)) {
+ dprintk("%s: failed to claim device %d:%d\n",
+ __func__, gd->major, gd->first_minor);
+ blkdev_put(bdev);
+ continue;
+ }
+
+ ret = alloc_add_disk(bdev, dlist);
+ if (ret < 0)
+ goto out_err;
+ dprintk("%s ADDED DEVICE capacity %ld, bd_block_size %d\n",
+ __func__,
+ (unsigned long)gd->capacity,
+ bdev->bd_block_size);
+
+ }
+ index++;
+ dprintk("%s returns index %d \n", __func__, index);
+ return index;
+
+out_err:
+ dprintk("%s Can't add disk to list. ERROR: %d\n", __func__, ret);
+ nfs4_blkdev_put(bdev);
+ return ret;
+}
+
+/* Destroy the temporary scsi disk list */
+void nfs4_blk_destroy_disk_list(struct list_head *dlist)
+{
+ struct visible_block_device *vis_dev;
+
+ dprintk("%s enter\n", __func__);
+ while (!list_empty(dlist)) {
+ vis_dev = list_first_entry(dlist, struct visible_block_device,
+ vi_node);
+ dprintk("%s removing device %d:%d\n", __func__,
+ MAJOR(vis_dev->vi_bdev->bd_dev),
+ MINOR(vis_dev->vi_bdev->bd_dev));
+ list_del(&vis_dev->vi_node);
+ if (!vis_dev->vi_mapped)
+ nfs4_blkdev_put(vis_dev->vi_bdev);
+ kfree(vis_dev);
+ }
+}
+
+/*
+ * Create a temporary list of all SCSI disks host can see, and that have not
+ * yet been claimed.
+ * shost_class: list of all registered scsi_hosts
+ * returns -errno on error, and #of devices found on success.
+ * XXX Loosely emulate scsi_host_lookup from scsi/host.c
+*/
+int nfs4_blk_create_scsi_disk_list(struct list_head *dlist)
+{
+ struct class *class = &shost_class;
+ struct class_device *cdev;
+ struct Scsi_Host *shost;
+ int ret = 0, index = 0;
+
+ dprintk("%s enter\n", __func__);
+
+ down(&class->sem);
+ list_for_each_entry(cdev, &class->children, node) {
+ dprintk("%s 1\n", __func__);
+ shost = class_to_shost(cdev);
+ ret = nfs4_blk_add_scsi_disk(shost, index, dlist);
+ dprintk("%s 2 ret %d\n", __func__, ret);
+ if (ret < 0)
+ goto out;
+ index = ret;
+ }
+out:
+ up(&class->sem);
+ return ret;
+}
--
1.5.3.3
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