fs/nfs/filelayout/filelayoutdev.c - third_party/kernel - Git at Google

 /*
  *  Device operations for the pnfs nfs4 file layout driver.
  *
  *  Copyright (c) 2002
  *  The Regents of the University of Michigan
  *  All Rights Reserved
  *
  *  Dean Hildebrand <dhildebz@umich.edu>
  *  Garth Goodson   <Garth.Goodson@netapp.com>
  *
  *  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 or warranty
  *  of any kind either express or implied, including without limitation
  *  the implied warranties of merchantability, fitness for a particular
  *  purpose, or noninfringement.  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 of 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/nfs_fs.h>
 #include <linux/vmalloc.h>
 #include <linux/module.h>

 #include "../internal.h"
 #include "../nfs4session.h"
 #include "filelayout.h"

 #define NFSDBG_FACILITY		NFSDBG_PNFS_LD

 static unsigned int dataserver_timeo = NFS4_DEF_DS_TIMEO;
 static unsigned int dataserver_retrans = NFS4_DEF_DS_RETRANS;

 void
 nfs4_fl_free_deviceid(struct nfs4_file_layout_dsaddr *dsaddr)
 {
 	struct nfs4_pnfs_ds *ds;
 	int i;

 	nfs4_print_deviceid(&dsaddr->id_node.deviceid);

 	for (i = 0; i < dsaddr->ds_num; i++) {
 		ds = dsaddr->ds_list[i];
 		if (ds != NULL)
 			nfs4_pnfs_ds_put(ds);
 	}
 	kfree(dsaddr->stripe_indices);
 	kfree_rcu(dsaddr, id_node.rcu);
 }

 /* Decode opaque device data and return the result */
 struct nfs4_file_layout_dsaddr *
 nfs4_fl_alloc_deviceid_node(struct nfs_server *server, struct pnfs_device *pdev,
 		gfp_t gfp_flags)
 {
 	int i;
 	u32 cnt, num;
 	u8 *indexp;
 	__be32 *p;
 	u8 *stripe_indices;
 	u8 max_stripe_index;
 	struct nfs4_file_layout_dsaddr *dsaddr = NULL;
 	struct xdr_stream stream;
 	struct xdr_buf buf;
 	struct page *scratch;
 	struct list_head dsaddrs;
 	struct nfs4_pnfs_ds_addr *da;

 	/* set up xdr stream */
 	scratch = alloc_page(gfp_flags);
 	if (!scratch)
 		goto out_err;

 	xdr_init_decode_pages(&stream, &buf, pdev->pages, pdev->pglen);
 	xdr_set_scratch_page(&stream, scratch);

 	/* Get the stripe count (number of stripe index) */
 	p = xdr_inline_decode(&stream, 4);
 	if (unlikely(!p))
 		goto out_err_free_scratch;

 	cnt = be32_to_cpup(p);
 	dprintk("%s stripe count  %d\n", __func__, cnt);
 	if (cnt > NFS4_PNFS_MAX_STRIPE_CNT) {
 		printk(KERN_WARNING "NFS: %s: stripe count %d greater than "
 		       "supported maximum %d\n", __func__,
 			cnt, NFS4_PNFS_MAX_STRIPE_CNT);
 		goto out_err_free_scratch;
 	}

 	/* read stripe indices */
 	stripe_indices = kcalloc(cnt, sizeof(u8), gfp_flags);
 	if (!stripe_indices)
 		goto out_err_free_scratch;

 	p = xdr_inline_decode(&stream, cnt << 2);
 	if (unlikely(!p))
 		goto out_err_free_stripe_indices;

 	indexp = &stripe_indices[0];
 	max_stripe_index = 0;
 	for (i = 0; i < cnt; i++) {
 		*indexp = be32_to_cpup(p++);
 		max_stripe_index = max(max_stripe_index, *indexp);
 		indexp++;
 	}

 	/* Check the multipath list count */
 	p = xdr_inline_decode(&stream, 4);
 	if (unlikely(!p))
 		goto out_err_free_stripe_indices;

 	num = be32_to_cpup(p);
 	dprintk("%s ds_num %u\n", __func__, num);
 	if (num > NFS4_PNFS_MAX_MULTI_CNT) {
 		printk(KERN_WARNING "NFS: %s: multipath count %d greater than "
 			"supported maximum %d\n", __func__,
 			num, NFS4_PNFS_MAX_MULTI_CNT);
 		goto out_err_free_stripe_indices;
 	}

 	/* validate stripe indices are all < num */
 	if (max_stripe_index >= num) {
 		printk(KERN_WARNING "NFS: %s: stripe index %u >= num ds %u\n",
 			__func__, max_stripe_index, num);
 		goto out_err_free_stripe_indices;
 	}

 	dsaddr = kzalloc(struct_size(dsaddr, ds_list, num), gfp_flags);
 	if (!dsaddr)
 		goto out_err_free_stripe_indices;

 	dsaddr->stripe_count = cnt;
 	dsaddr->stripe_indices = stripe_indices;
 	stripe_indices = NULL;
 	dsaddr->ds_num = num;
 	nfs4_init_deviceid_node(&dsaddr->id_node, server, &pdev->dev_id);

 	INIT_LIST_HEAD(&dsaddrs);

 	for (i = 0; i < dsaddr->ds_num; i++) {
 		int j;
 		u32 mp_count;

 		p = xdr_inline_decode(&stream, 4);
 		if (unlikely(!p))
 			goto out_err_free_deviceid;

 		mp_count = be32_to_cpup(p); /* multipath count */
 		for (j = 0; j < mp_count; j++) {
 			da = nfs4_decode_mp_ds_addr(server->nfs_client->cl_net,
 						    &stream, gfp_flags);
 			if (da)
 				list_add_tail(&da->da_node, &dsaddrs);
 		}
 		if (list_empty(&dsaddrs)) {
 			dprintk("%s: no suitable DS addresses found\n",
 				__func__);
 			goto out_err_free_deviceid;
 		}

 		dsaddr->ds_list[i] = nfs4_pnfs_ds_add(&dsaddrs, gfp_flags);
 		if (!dsaddr->ds_list[i])
 			goto out_err_drain_dsaddrs;

 		/* If DS was already in cache, free ds addrs */
 		while (!list_empty(&dsaddrs)) {
 			da = list_first_entry(&dsaddrs,
 					      struct nfs4_pnfs_ds_addr,
 					      da_node);
 			list_del_init(&da->da_node);
 			kfree(da->da_remotestr);
 			kfree(da);
 		}
 	}

 	__free_page(scratch);
 	return dsaddr;

 out_err_drain_dsaddrs:
 	while (!list_empty(&dsaddrs)) {
 		da = list_first_entry(&dsaddrs, struct nfs4_pnfs_ds_addr,
 				      da_node);
 		list_del_init(&da->da_node);
 		kfree(da->da_remotestr);
 		kfree(da);
 	}
 out_err_free_deviceid:
 	nfs4_fl_free_deviceid(dsaddr);
 	/* stripe_indicies was part of dsaddr */
 	goto out_err_free_scratch;
 out_err_free_stripe_indices:
 	kfree(stripe_indices);
 out_err_free_scratch:
 	__free_page(scratch);
 out_err:
 	dprintk("%s ERROR: returning NULL\n", __func__);
 	return NULL;
 }

 void
 nfs4_fl_put_deviceid(struct nfs4_file_layout_dsaddr *dsaddr)
 {
 	nfs4_put_deviceid_node(&dsaddr->id_node);
 }

 /*
  * Want res = (offset - layout->pattern_offset)/ layout->stripe_unit
  * Then: ((res + fsi) % dsaddr->stripe_count)
  */
 u32
 nfs4_fl_calc_j_index(struct pnfs_layout_segment *lseg, loff_t offset)
 {
 	struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
 	u64 tmp;

 	tmp = offset - flseg->pattern_offset;
 	do_div(tmp, flseg->stripe_unit);
 	tmp += flseg->first_stripe_index;
 	return do_div(tmp, flseg->dsaddr->stripe_count);
 }

 u32
 nfs4_fl_calc_ds_index(struct pnfs_layout_segment *lseg, u32 j)
 {
 	return FILELAYOUT_LSEG(lseg)->dsaddr->stripe_indices[j];
 }

 struct nfs_fh *
 nfs4_fl_select_ds_fh(struct pnfs_layout_segment *lseg, u32 j)
 {
 	struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
 	u32 i;

 	if (flseg->stripe_type == STRIPE_SPARSE) {
 		if (flseg->num_fh == 1)
 			i = 0;
 		else if (flseg->num_fh == 0)
 			/* Use the MDS OPEN fh set in nfs_read_rpcsetup */
 			return NULL;
 		else
 			i = nfs4_fl_calc_ds_index(lseg, j);
 	} else
 		i = j;
 	return flseg->fh_array[i];
 }

 /* Upon return, either ds is connected, or ds is NULL */
 struct nfs4_pnfs_ds *
 nfs4_fl_prepare_ds(struct pnfs_layout_segment *lseg, u32 ds_idx)
 {
 	struct nfs4_file_layout_dsaddr *dsaddr = FILELAYOUT_LSEG(lseg)->dsaddr;
 	struct nfs4_pnfs_ds *ds = dsaddr->ds_list[ds_idx];
 	struct nfs4_deviceid_node *devid = FILELAYOUT_DEVID_NODE(lseg);
 	struct nfs4_pnfs_ds *ret = ds;
 	struct nfs_server *s = NFS_SERVER(lseg->pls_layout->plh_inode);
 	int status;

 	if (ds == NULL) {
 		printk(KERN_ERR "NFS: %s: No data server for offset index %d\n",
 			__func__, ds_idx);
 		pnfs_generic_mark_devid_invalid(devid);
 		goto out;
 	}
 	smp_rmb();
 	if (ds->ds_clp)
 		goto out_test_devid;

 	status = nfs4_pnfs_ds_connect(s, ds, devid, dataserver_timeo,
 			     dataserver_retrans, 4,
 			     s->nfs_client->cl_minorversion);
 	if (status) {
 		nfs4_mark_deviceid_unavailable(devid);
 		ret = NULL;
 		goto out;
 	}

 out_test_devid:
 	if (ret->ds_clp == NULL ||
 	    filelayout_test_devid_unavailable(devid))
 		ret = NULL;
 out:
 	return ret;
 }

 module_param(dataserver_retrans, uint, 0644);
 MODULE_PARM_DESC(dataserver_retrans, "The  number of times the NFSv4.1 client "
 			"retries a request before it attempts further "
 			" recovery  action.");
 module_param(dataserver_timeo, uint, 0644);
 MODULE_PARM_DESC(dataserver_timeo, "The time (in tenths of a second) the "
 			"NFSv4.1  client  waits for a response from a "
 			" data server before it retries an NFS request.");
	/*
	* Device operations for the pnfs nfs4 file layout driver.
	*
	* Copyright (c) 2002
	* The Regents of the University of Michigan
	* All Rights Reserved
	*
	* Dean Hildebrand <dhildebz@umich.edu>
	* Garth Goodson <Garth.Goodson@netapp.com>
	*
	* 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 or warranty
	* of any kind either express or implied, including without limitation
	* the implied warranties of merchantability, fitness for a particular
	* purpose, or noninfringement. 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 of 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/nfs_fs.h>
	#include <linux/vmalloc.h>
	#include <linux/module.h>

	#include "../internal.h"
	#include "../nfs4session.h"
	#include "filelayout.h"

	#define NFSDBG_FACILITY NFSDBG_PNFS_LD

	static unsigned int dataserver_timeo = NFS4_DEF_DS_TIMEO;
	static unsigned int dataserver_retrans = NFS4_DEF_DS_RETRANS;

	void
	nfs4_fl_free_deviceid(struct nfs4_file_layout_dsaddr *dsaddr)
	{
	struct nfs4_pnfs_ds *ds;
	int i;

	nfs4_print_deviceid(&dsaddr->id_node.deviceid);

	for (i = 0; i < dsaddr->ds_num; i++) {
	ds = dsaddr->ds_list[i];
	if (ds != NULL)
	nfs4_pnfs_ds_put(ds);
	}
	kfree(dsaddr->stripe_indices);
	kfree_rcu(dsaddr, id_node.rcu);
	}

	/* Decode opaque device data and return the result */
	struct nfs4_file_layout_dsaddr *
	nfs4_fl_alloc_deviceid_node(struct nfs_server server, struct pnfs_device pdev,
	gfp_t gfp_flags)
	{
	int i;
	u32 cnt, num;
	u8 *indexp;
	__be32 *p;
	u8 *stripe_indices;
	u8 max_stripe_index;
	struct nfs4_file_layout_dsaddr *dsaddr = NULL;
	struct xdr_stream stream;
	struct xdr_buf buf;
	struct page *scratch;
	struct list_head dsaddrs;
	struct nfs4_pnfs_ds_addr *da;

	/* set up xdr stream */
	scratch = alloc_page(gfp_flags);
	if (!scratch)
	goto out_err;

	xdr_init_decode_pages(&stream, &buf, pdev->pages, pdev->pglen);
	xdr_set_scratch_page(&stream, scratch);

	/* Get the stripe count (number of stripe index) */
	p = xdr_inline_decode(&stream, 4);
	if (unlikely(!p))
	goto out_err_free_scratch;

	cnt = be32_to_cpup(p);
	dprintk("%s stripe count %d\n", __func__, cnt);
	if (cnt > NFS4_PNFS_MAX_STRIPE_CNT) {
	printk(KERN_WARNING "NFS: %s: stripe count %d greater than "
	"supported maximum %d\n", __func__,
	cnt, NFS4_PNFS_MAX_STRIPE_CNT);
	goto out_err_free_scratch;
	}

	/* read stripe indices */
	stripe_indices = kcalloc(cnt, sizeof(u8), gfp_flags);
	if (!stripe_indices)
	goto out_err_free_scratch;

	p = xdr_inline_decode(&stream, cnt << 2);
	if (unlikely(!p))
	goto out_err_free_stripe_indices;

	indexp = &stripe_indices[0];
	max_stripe_index = 0;
	for (i = 0; i < cnt; i++) {
	*indexp = be32_to_cpup(p++);
	max_stripe_index = max(max_stripe_index, *indexp);
	indexp++;
	}

	/* Check the multipath list count */
	p = xdr_inline_decode(&stream, 4);
	if (unlikely(!p))
	goto out_err_free_stripe_indices;

	num = be32_to_cpup(p);
	dprintk("%s ds_num %u\n", __func__, num);
	if (num > NFS4_PNFS_MAX_MULTI_CNT) {
	printk(KERN_WARNING "NFS: %s: multipath count %d greater than "
	"supported maximum %d\n", __func__,
	num, NFS4_PNFS_MAX_MULTI_CNT);
	goto out_err_free_stripe_indices;
	}

	/* validate stripe indices are all < num */
	if (max_stripe_index >= num) {
	printk(KERN_WARNING "NFS: %s: stripe index %u >= num ds %u\n",
	__func__, max_stripe_index, num);
	goto out_err_free_stripe_indices;
	}

	dsaddr = kzalloc(struct_size(dsaddr, ds_list, num), gfp_flags);
	if (!dsaddr)
	goto out_err_free_stripe_indices;

	dsaddr->stripe_count = cnt;
	dsaddr->stripe_indices = stripe_indices;
	stripe_indices = NULL;
	dsaddr->ds_num = num;
	nfs4_init_deviceid_node(&dsaddr->id_node, server, &pdev->dev_id);

	INIT_LIST_HEAD(&dsaddrs);

	for (i = 0; i < dsaddr->ds_num; i++) {
	int j;
	u32 mp_count;

	p = xdr_inline_decode(&stream, 4);
	if (unlikely(!p))
	goto out_err_free_deviceid;

	mp_count = be32_to_cpup(p); /* multipath count */
	for (j = 0; j < mp_count; j++) {
	da = nfs4_decode_mp_ds_addr(server->nfs_client->cl_net,
	&stream, gfp_flags);
	if (da)
	list_add_tail(&da->da_node, &dsaddrs);
	}
	if (list_empty(&dsaddrs)) {
	dprintk("%s: no suitable DS addresses found\n",
	__func__);
	goto out_err_free_deviceid;
	}

	dsaddr->ds_list[i] = nfs4_pnfs_ds_add(&dsaddrs, gfp_flags);
	if (!dsaddr->ds_list[i])
	goto out_err_drain_dsaddrs;

	/* If DS was already in cache, free ds addrs */
	while (!list_empty(&dsaddrs)) {
	da = list_first_entry(&dsaddrs,
	struct nfs4_pnfs_ds_addr,
	da_node);
	list_del_init(&da->da_node);
	kfree(da->da_remotestr);
	kfree(da);
	}
	}

	__free_page(scratch);
	return dsaddr;

	out_err_drain_dsaddrs:
	while (!list_empty(&dsaddrs)) {
	da = list_first_entry(&dsaddrs, struct nfs4_pnfs_ds_addr,
	da_node);
	list_del_init(&da->da_node);
	kfree(da->da_remotestr);
	kfree(da);
	}
	out_err_free_deviceid:
	nfs4_fl_free_deviceid(dsaddr);
	/* stripe_indicies was part of dsaddr */
	goto out_err_free_scratch;
	out_err_free_stripe_indices:
	kfree(stripe_indices);
	out_err_free_scratch:
	__free_page(scratch);
	out_err:
	dprintk("%s ERROR: returning NULL\n", __func__);
	return NULL;
	}

	void
	nfs4_fl_put_deviceid(struct nfs4_file_layout_dsaddr *dsaddr)
	{
	nfs4_put_deviceid_node(&dsaddr->id_node);
	}

	/*
	* Want res = (offset - layout->pattern_offset)/ layout->stripe_unit
	* Then: ((res + fsi) % dsaddr->stripe_count)
	*/
	u32
	nfs4_fl_calc_j_index(struct pnfs_layout_segment *lseg, loff_t offset)
	{
	struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
	u64 tmp;

	tmp = offset - flseg->pattern_offset;
	do_div(tmp, flseg->stripe_unit);
	tmp += flseg->first_stripe_index;
	return do_div(tmp, flseg->dsaddr->stripe_count);
	}

	u32
	nfs4_fl_calc_ds_index(struct pnfs_layout_segment *lseg, u32 j)
	{
	return FILELAYOUT_LSEG(lseg)->dsaddr->stripe_indices[j];
	}

	struct nfs_fh *
	nfs4_fl_select_ds_fh(struct pnfs_layout_segment *lseg, u32 j)
	{
	struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
	u32 i;

	if (flseg->stripe_type == STRIPE_SPARSE) {
	if (flseg->num_fh == 1)
	i = 0;
	else if (flseg->num_fh == 0)
	/* Use the MDS OPEN fh set in nfs_read_rpcsetup */
	return NULL;
	else
	i = nfs4_fl_calc_ds_index(lseg, j);
	} else
	i = j;
	return flseg->fh_array[i];
	}

	/* Upon return, either ds is connected, or ds is NULL */
	struct nfs4_pnfs_ds *
	nfs4_fl_prepare_ds(struct pnfs_layout_segment *lseg, u32 ds_idx)
	{
	struct nfs4_file_layout_dsaddr *dsaddr = FILELAYOUT_LSEG(lseg)->dsaddr;
	struct nfs4_pnfs_ds *ds = dsaddr->ds_list[ds_idx];
	struct nfs4_deviceid_node *devid = FILELAYOUT_DEVID_NODE(lseg);
	struct nfs4_pnfs_ds *ret = ds;
	struct nfs_server *s = NFS_SERVER(lseg->pls_layout->plh_inode);
	int status;

	if (ds == NULL) {
	printk(KERN_ERR "NFS: %s: No data server for offset index %d\n",
	__func__, ds_idx);
	pnfs_generic_mark_devid_invalid(devid);
	goto out;
	}
	smp_rmb();
	if (ds->ds_clp)
	goto out_test_devid;

	status = nfs4_pnfs_ds_connect(s, ds, devid, dataserver_timeo,
	dataserver_retrans, 4,
	s->nfs_client->cl_minorversion);
	if (status) {
	nfs4_mark_deviceid_unavailable(devid);
	ret = NULL;
	goto out;
	}

	out_test_devid:
	if (ret->ds_clp == NULL \|\|
	filelayout_test_devid_unavailable(devid))
	ret = NULL;
	out:
	return ret;
	}

	module_param(dataserver_retrans, uint, 0644);
	MODULE_PARM_DESC(dataserver_retrans, "The number of times the NFSv4.1 client "
	"retries a request before it attempts further "
	" recovery action.");
	module_param(dataserver_timeo, uint, 0644);
	MODULE_PARM_DESC(dataserver_timeo, "The time (in tenths of a second) the "
	"NFSv4.1 client waits for a response from a "
	" data server before it retries an NFS request.");