cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

filelayoutdev.c (8514B)


      1/*
      2 *  Device operations for the pnfs nfs4 file layout driver.
      3 *
      4 *  Copyright (c) 2002
      5 *  The Regents of the University of Michigan
      6 *  All Rights Reserved
      7 *
      8 *  Dean Hildebrand <dhildebz@umich.edu>
      9 *  Garth Goodson   <Garth.Goodson@netapp.com>
     10 *
     11 *  Permission is granted to use, copy, create derivative works, and
     12 *  redistribute this software and such derivative works for any purpose,
     13 *  so long as the name of the University of Michigan is not used in
     14 *  any advertising or publicity pertaining to the use or distribution
     15 *  of this software without specific, written prior authorization. If
     16 *  the above copyright notice or any other identification of the
     17 *  University of Michigan is included in any copy of any portion of
     18 *  this software, then the disclaimer below must also be included.
     19 *
     20 *  This software is provided as is, without representation or warranty
     21 *  of any kind either express or implied, including without limitation
     22 *  the implied warranties of merchantability, fitness for a particular
     23 *  purpose, or noninfringement.  The Regents of the University of
     24 *  Michigan shall not be liable for any damages, including special,
     25 *  indirect, incidental, or consequential damages, with respect to any
     26 *  claim arising out of or in connection with the use of the software,
     27 *  even if it has been or is hereafter advised of the possibility of
     28 *  such damages.
     29 */
     30
     31#include <linux/nfs_fs.h>
     32#include <linux/vmalloc.h>
     33#include <linux/module.h>
     34
     35#include "../internal.h"
     36#include "../nfs4session.h"
     37#include "filelayout.h"
     38
     39#define NFSDBG_FACILITY		NFSDBG_PNFS_LD
     40
     41static unsigned int dataserver_timeo = NFS4_DEF_DS_TIMEO;
     42static unsigned int dataserver_retrans = NFS4_DEF_DS_RETRANS;
     43
     44void
     45nfs4_fl_free_deviceid(struct nfs4_file_layout_dsaddr *dsaddr)
     46{
     47	struct nfs4_pnfs_ds *ds;
     48	int i;
     49
     50	nfs4_print_deviceid(&dsaddr->id_node.deviceid);
     51
     52	for (i = 0; i < dsaddr->ds_num; i++) {
     53		ds = dsaddr->ds_list[i];
     54		if (ds != NULL)
     55			nfs4_pnfs_ds_put(ds);
     56	}
     57	kfree(dsaddr->stripe_indices);
     58	kfree_rcu(dsaddr, id_node.rcu);
     59}
     60
     61/* Decode opaque device data and return the result */
     62struct nfs4_file_layout_dsaddr *
     63nfs4_fl_alloc_deviceid_node(struct nfs_server *server, struct pnfs_device *pdev,
     64		gfp_t gfp_flags)
     65{
     66	int i;
     67	u32 cnt, num;
     68	u8 *indexp;
     69	__be32 *p;
     70	u8 *stripe_indices;
     71	u8 max_stripe_index;
     72	struct nfs4_file_layout_dsaddr *dsaddr = NULL;
     73	struct xdr_stream stream;
     74	struct xdr_buf buf;
     75	struct page *scratch;
     76	struct list_head dsaddrs;
     77	struct nfs4_pnfs_ds_addr *da;
     78
     79	/* set up xdr stream */
     80	scratch = alloc_page(gfp_flags);
     81	if (!scratch)
     82		goto out_err;
     83
     84	xdr_init_decode_pages(&stream, &buf, pdev->pages, pdev->pglen);
     85	xdr_set_scratch_page(&stream, scratch);
     86
     87	/* Get the stripe count (number of stripe index) */
     88	p = xdr_inline_decode(&stream, 4);
     89	if (unlikely(!p))
     90		goto out_err_free_scratch;
     91
     92	cnt = be32_to_cpup(p);
     93	dprintk("%s stripe count  %d\n", __func__, cnt);
     94	if (cnt > NFS4_PNFS_MAX_STRIPE_CNT) {
     95		printk(KERN_WARNING "NFS: %s: stripe count %d greater than "
     96		       "supported maximum %d\n", __func__,
     97			cnt, NFS4_PNFS_MAX_STRIPE_CNT);
     98		goto out_err_free_scratch;
     99	}
    100
    101	/* read stripe indices */
    102	stripe_indices = kcalloc(cnt, sizeof(u8), gfp_flags);
    103	if (!stripe_indices)
    104		goto out_err_free_scratch;
    105
    106	p = xdr_inline_decode(&stream, cnt << 2);
    107	if (unlikely(!p))
    108		goto out_err_free_stripe_indices;
    109
    110	indexp = &stripe_indices[0];
    111	max_stripe_index = 0;
    112	for (i = 0; i < cnt; i++) {
    113		*indexp = be32_to_cpup(p++);
    114		max_stripe_index = max(max_stripe_index, *indexp);
    115		indexp++;
    116	}
    117
    118	/* Check the multipath list count */
    119	p = xdr_inline_decode(&stream, 4);
    120	if (unlikely(!p))
    121		goto out_err_free_stripe_indices;
    122
    123	num = be32_to_cpup(p);
    124	dprintk("%s ds_num %u\n", __func__, num);
    125	if (num > NFS4_PNFS_MAX_MULTI_CNT) {
    126		printk(KERN_WARNING "NFS: %s: multipath count %d greater than "
    127			"supported maximum %d\n", __func__,
    128			num, NFS4_PNFS_MAX_MULTI_CNT);
    129		goto out_err_free_stripe_indices;
    130	}
    131
    132	/* validate stripe indices are all < num */
    133	if (max_stripe_index >= num) {
    134		printk(KERN_WARNING "NFS: %s: stripe index %u >= num ds %u\n",
    135			__func__, max_stripe_index, num);
    136		goto out_err_free_stripe_indices;
    137	}
    138
    139	dsaddr = kzalloc(struct_size(dsaddr, ds_list, num), gfp_flags);
    140	if (!dsaddr)
    141		goto out_err_free_stripe_indices;
    142
    143	dsaddr->stripe_count = cnt;
    144	dsaddr->stripe_indices = stripe_indices;
    145	stripe_indices = NULL;
    146	dsaddr->ds_num = num;
    147	nfs4_init_deviceid_node(&dsaddr->id_node, server, &pdev->dev_id);
    148
    149	INIT_LIST_HEAD(&dsaddrs);
    150
    151	for (i = 0; i < dsaddr->ds_num; i++) {
    152		int j;
    153		u32 mp_count;
    154
    155		p = xdr_inline_decode(&stream, 4);
    156		if (unlikely(!p))
    157			goto out_err_free_deviceid;
    158
    159		mp_count = be32_to_cpup(p); /* multipath count */
    160		for (j = 0; j < mp_count; j++) {
    161			da = nfs4_decode_mp_ds_addr(server->nfs_client->cl_net,
    162						    &stream, gfp_flags);
    163			if (da)
    164				list_add_tail(&da->da_node, &dsaddrs);
    165		}
    166		if (list_empty(&dsaddrs)) {
    167			dprintk("%s: no suitable DS addresses found\n",
    168				__func__);
    169			goto out_err_free_deviceid;
    170		}
    171
    172		dsaddr->ds_list[i] = nfs4_pnfs_ds_add(&dsaddrs, gfp_flags);
    173		if (!dsaddr->ds_list[i])
    174			goto out_err_drain_dsaddrs;
    175
    176		/* If DS was already in cache, free ds addrs */
    177		while (!list_empty(&dsaddrs)) {
    178			da = list_first_entry(&dsaddrs,
    179					      struct nfs4_pnfs_ds_addr,
    180					      da_node);
    181			list_del_init(&da->da_node);
    182			kfree(da->da_remotestr);
    183			kfree(da);
    184		}
    185	}
    186
    187	__free_page(scratch);
    188	return dsaddr;
    189
    190out_err_drain_dsaddrs:
    191	while (!list_empty(&dsaddrs)) {
    192		da = list_first_entry(&dsaddrs, struct nfs4_pnfs_ds_addr,
    193				      da_node);
    194		list_del_init(&da->da_node);
    195		kfree(da->da_remotestr);
    196		kfree(da);
    197	}
    198out_err_free_deviceid:
    199	nfs4_fl_free_deviceid(dsaddr);
    200	/* stripe_indicies was part of dsaddr */
    201	goto out_err_free_scratch;
    202out_err_free_stripe_indices:
    203	kfree(stripe_indices);
    204out_err_free_scratch:
    205	__free_page(scratch);
    206out_err:
    207	dprintk("%s ERROR: returning NULL\n", __func__);
    208	return NULL;
    209}
    210
    211void
    212nfs4_fl_put_deviceid(struct nfs4_file_layout_dsaddr *dsaddr)
    213{
    214	nfs4_put_deviceid_node(&dsaddr->id_node);
    215}
    216
    217/*
    218 * Want res = (offset - layout->pattern_offset)/ layout->stripe_unit
    219 * Then: ((res + fsi) % dsaddr->stripe_count)
    220 */
    221u32
    222nfs4_fl_calc_j_index(struct pnfs_layout_segment *lseg, loff_t offset)
    223{
    224	struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
    225	u64 tmp;
    226
    227	tmp = offset - flseg->pattern_offset;
    228	do_div(tmp, flseg->stripe_unit);
    229	tmp += flseg->first_stripe_index;
    230	return do_div(tmp, flseg->dsaddr->stripe_count);
    231}
    232
    233u32
    234nfs4_fl_calc_ds_index(struct pnfs_layout_segment *lseg, u32 j)
    235{
    236	return FILELAYOUT_LSEG(lseg)->dsaddr->stripe_indices[j];
    237}
    238
    239struct nfs_fh *
    240nfs4_fl_select_ds_fh(struct pnfs_layout_segment *lseg, u32 j)
    241{
    242	struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
    243	u32 i;
    244
    245	if (flseg->stripe_type == STRIPE_SPARSE) {
    246		if (flseg->num_fh == 1)
    247			i = 0;
    248		else if (flseg->num_fh == 0)
    249			/* Use the MDS OPEN fh set in nfs_read_rpcsetup */
    250			return NULL;
    251		else
    252			i = nfs4_fl_calc_ds_index(lseg, j);
    253	} else
    254		i = j;
    255	return flseg->fh_array[i];
    256}
    257
    258/* Upon return, either ds is connected, or ds is NULL */
    259struct nfs4_pnfs_ds *
    260nfs4_fl_prepare_ds(struct pnfs_layout_segment *lseg, u32 ds_idx)
    261{
    262	struct nfs4_file_layout_dsaddr *dsaddr = FILELAYOUT_LSEG(lseg)->dsaddr;
    263	struct nfs4_pnfs_ds *ds = dsaddr->ds_list[ds_idx];
    264	struct nfs4_deviceid_node *devid = FILELAYOUT_DEVID_NODE(lseg);
    265	struct nfs4_pnfs_ds *ret = ds;
    266	struct nfs_server *s = NFS_SERVER(lseg->pls_layout->plh_inode);
    267	int status;
    268
    269	if (ds == NULL) {
    270		printk(KERN_ERR "NFS: %s: No data server for offset index %d\n",
    271			__func__, ds_idx);
    272		pnfs_generic_mark_devid_invalid(devid);
    273		goto out;
    274	}
    275	smp_rmb();
    276	if (ds->ds_clp)
    277		goto out_test_devid;
    278
    279	status = nfs4_pnfs_ds_connect(s, ds, devid, dataserver_timeo,
    280			     dataserver_retrans, 4,
    281			     s->nfs_client->cl_minorversion);
    282	if (status) {
    283		nfs4_mark_deviceid_unavailable(devid);
    284		ret = NULL;
    285		goto out;
    286	}
    287
    288out_test_devid:
    289	if (ret->ds_clp == NULL ||
    290	    filelayout_test_devid_unavailable(devid))
    291		ret = NULL;
    292out:
    293	return ret;
    294}
    295
    296module_param(dataserver_retrans, uint, 0644);
    297MODULE_PARM_DESC(dataserver_retrans, "The  number of times the NFSv4.1 client "
    298			"retries a request before it attempts further "
    299			" recovery  action.");
    300module_param(dataserver_timeo, uint, 0644);
    301MODULE_PARM_DESC(dataserver_timeo, "The time (in tenths of a second) the "
    302			"NFSv4.1  client  waits for a response from a "
    303			" data server before it retries an NFS request.");