[linux-block.git] / fs / nfs / fscache.c

// SPDX-License-Identifier: GPL-2.0-or-later
/* NFS filesystem cache interface
 *
 * Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 */

#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/nfs_fs.h>
#include <linux/nfs_fs_sb.h>
#include <linux/in6.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/iversion.h>
#include <linux/xarray.h>
#include <linux/fscache.h>
#include <linux/netfs.h>

#include "internal.h"
#include "iostat.h"
#include "fscache.h"
#include "nfstrace.h"

#define NFS_MAX_KEY_LEN 1000

static bool nfs_append_int(char *key, int *_len, unsigned long long x)
{
	if (*_len > NFS_MAX_KEY_LEN)
		return false;
	if (x == 0)
		key[(*_len)++] = ',';
	else
		*_len += sprintf(key + *_len, ",%llx", x);
	return true;
}

/*
 * Get the per-client index cookie for an NFS client if the appropriate mount
 * flag was set
 * - We always try and get an index cookie for the client, but get filehandle
 *   cookies on a per-superblock basis, depending on the mount flags
 */
static bool nfs_fscache_get_client_key(struct nfs_client *clp,
				       char *key, int *_len)
{
	const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) &clp->cl_addr;
	const struct sockaddr_in *sin = (struct sockaddr_in *) &clp->cl_addr;

	*_len += snprintf(key + *_len, NFS_MAX_KEY_LEN - *_len,
			  ",%u.%u,%x",
			  clp->rpc_ops->version,
			  clp->cl_minorversion,
			  clp->cl_addr.ss_family);

	switch (clp->cl_addr.ss_family) {
	case AF_INET:
		if (!nfs_append_int(key, _len, sin->sin_port) ||
		    !nfs_append_int(key, _len, sin->sin_addr.s_addr))
			return false;
		return true;

	case AF_INET6:
		if (!nfs_append_int(key, _len, sin6->sin6_port) ||
		    !nfs_append_int(key, _len, sin6->sin6_addr.s6_addr32[0]) ||
		    !nfs_append_int(key, _len, sin6->sin6_addr.s6_addr32[1]) ||
		    !nfs_append_int(key, _len, sin6->sin6_addr.s6_addr32[2]) ||
		    !nfs_append_int(key, _len, sin6->sin6_addr.s6_addr32[3]))
			return false;
		return true;

	default:
		printk(KERN_WARNING "NFS: Unknown network family '%d'\n",
		       clp->cl_addr.ss_family);
		return false;
	}
}

/*
 * Get the cache cookie for an NFS superblock.
 *
 * The default uniquifier is just an empty string, but it may be overridden
 * either by the 'fsc=xxx' option to mount, or by inheriting it from the parent
 * superblock across an automount point of some nature.
 */
int nfs_fscache_get_super_cookie(struct super_block *sb, const char *uniq, int ulen)
{
	struct fscache_volume *vcookie;
	struct nfs_server *nfss = NFS_SB(sb);
	unsigned int len = 3;
	char *key;

	if (uniq) {
		nfss->fscache_uniq = kmemdup_nul(uniq, ulen, GFP_KERNEL);
		if (!nfss->fscache_uniq)
			return -ENOMEM;
	}

	key = kmalloc(NFS_MAX_KEY_LEN + 24, GFP_KERNEL);
	if (!key)
		return -ENOMEM;

	memcpy(key, "nfs", 3);
	if (!nfs_fscache_get_client_key(nfss->nfs_client, key, &len) ||
	    !nfs_append_int(key, &len, nfss->fsid.major) ||
	    !nfs_append_int(key, &len, nfss->fsid.minor) ||
	    !nfs_append_int(key, &len, sb->s_flags & NFS_SB_MASK) ||
	    !nfs_append_int(key, &len, nfss->flags) ||
	    !nfs_append_int(key, &len, nfss->rsize) ||
	    !nfs_append_int(key, &len, nfss->wsize) ||
	    !nfs_append_int(key, &len, nfss->acregmin) ||
	    !nfs_append_int(key, &len, nfss->acregmax) ||
	    !nfs_append_int(key, &len, nfss->acdirmin) ||
	    !nfs_append_int(key, &len, nfss->acdirmax) ||
	    !nfs_append_int(key, &len, nfss->client->cl_auth->au_flavor))
		goto out;

	if (ulen > 0) {
		if (ulen > NFS_MAX_KEY_LEN - len)
			goto out;
		key[len++] = ',';
		memcpy(key + len, uniq, ulen);
		len += ulen;
	}
	key[len] = 0;

	/* create a cache index for looking up filehandles */
	vcookie = fscache_acquire_volume(key,
					 NULL, /* preferred_cache */
					 NULL, 0 /* coherency_data */);
	if (IS_ERR(vcookie)) {
		if (vcookie != ERR_PTR(-EBUSY)) {
			kfree(key);
			return PTR_ERR(vcookie);
		}
		pr_err("NFS: Cache volume key already in use (%s)\n", key);
		vcookie = NULL;
	}
	nfss->fscache = vcookie;

out:
	kfree(key);
	return 0;
}

/*
 * release a per-superblock cookie
 */
void nfs_fscache_release_super_cookie(struct super_block *sb)
{
	struct nfs_server *nfss = NFS_SB(sb);

	fscache_relinquish_volume(nfss->fscache, NULL, false);
	nfss->fscache = NULL;
	kfree(nfss->fscache_uniq);
}

/*
 * Initialise the per-inode cache cookie pointer for an NFS inode.
 */
void nfs_fscache_init_inode(struct inode *inode)
{
	struct nfs_fscache_inode_auxdata auxdata;
	struct nfs_server *nfss = NFS_SERVER(inode);
	struct nfs_inode *nfsi = NFS_I(inode);

	netfs_inode(inode)->cache = NULL;
	if (!(nfss->fscache && S_ISREG(inode->i_mode)))
		return;

	nfs_fscache_update_auxdata(&auxdata, inode);

	netfs_inode(inode)->cache = fscache_acquire_cookie(
					       nfss->fscache,
					       0,
					       nfsi->fh.data, /* index_key */
					       nfsi->fh.size,
					       &auxdata,      /* aux_data */
					       sizeof(auxdata),
					       i_size_read(inode));
}

/*
 * Release a per-inode cookie.
 */
void nfs_fscache_clear_inode(struct inode *inode)
{
	fscache_relinquish_cookie(netfs_i_cookie(netfs_inode(inode)), false);
	netfs_inode(inode)->cache = NULL;
}

/*
 * Enable or disable caching for a file that is being opened as appropriate.
 * The cookie is allocated when the inode is initialised, but is not enabled at
 * that time.  Enablement is deferred to file-open time to avoid stat() and
 * access() thrashing the cache.
 *
 * For now, with NFS, only regular files that are open read-only will be able
 * to use the cache.
 *
 * We enable the cache for an inode if we open it read-only and it isn't
 * currently open for writing.  We disable the cache if the inode is open
 * write-only.
 *
 * The caller uses the file struct to pin i_writecount on the inode before
 * calling us when a file is opened for writing, so we can make use of that.
 *
 * Note that this may be invoked multiple times in parallel by parallel
 * nfs_open() functions.
 */
void nfs_fscache_open_file(struct inode *inode, struct file *filp)
{
	struct nfs_fscache_inode_auxdata auxdata;
	struct fscache_cookie *cookie = netfs_i_cookie(netfs_inode(inode));
	bool open_for_write = inode_is_open_for_write(inode);

	if (!fscache_cookie_valid(cookie))
		return;

	fscache_use_cookie(cookie, open_for_write);
	if (open_for_write) {
		nfs_fscache_update_auxdata(&auxdata, inode);
		fscache_invalidate(cookie, &auxdata, i_size_read(inode),
				   FSCACHE_INVAL_DIO_WRITE);
	}
}
EXPORT_SYMBOL_GPL(nfs_fscache_open_file);

void nfs_fscache_release_file(struct inode *inode, struct file *filp)
{
	struct nfs_fscache_inode_auxdata auxdata;
	struct fscache_cookie *cookie = netfs_i_cookie(netfs_inode(inode));
	loff_t i_size = i_size_read(inode);

	nfs_fscache_update_auxdata(&auxdata, inode);
	fscache_unuse_cookie(cookie, &auxdata, &i_size);
}

int nfs_netfs_read_folio(struct file *file, struct folio *folio)
{
	if (!netfs_inode(folio_inode(folio))->cache)
		return -ENOBUFS;

	return netfs_read_folio(file, folio);
}

int nfs_netfs_readahead(struct readahead_control *ractl)
{
	struct inode *inode = ractl->mapping->host;

	if (!netfs_inode(inode)->cache)
		return -ENOBUFS;

	netfs_readahead(ractl);
	return 0;
}

static atomic_t nfs_netfs_debug_id;
static int nfs_netfs_init_request(struct netfs_io_request *rreq, struct file *file)
{
	rreq->netfs_priv = get_nfs_open_context(nfs_file_open_context(file));
	rreq->debug_id = atomic_inc_return(&nfs_netfs_debug_id);

	return 0;
}

static void nfs_netfs_free_request(struct netfs_io_request *rreq)
{
	put_nfs_open_context(rreq->netfs_priv);
}

static inline int nfs_netfs_begin_cache_operation(struct netfs_io_request *rreq)
{
	return fscache_begin_read_operation(&rreq->cache_resources,
					    netfs_i_cookie(netfs_inode(rreq->inode)));
}

static struct nfs_netfs_io_data *nfs_netfs_alloc(struct netfs_io_subrequest *sreq)
{
	struct nfs_netfs_io_data *netfs;

	netfs = kzalloc(sizeof(*netfs), GFP_KERNEL_ACCOUNT);
	if (!netfs)
		return NULL;
	netfs->sreq = sreq;
	refcount_set(&netfs->refcount, 1);
	return netfs;
}

static bool nfs_netfs_clamp_length(struct netfs_io_subrequest *sreq)
{
	size_t	rsize = NFS_SB(sreq->rreq->inode->i_sb)->rsize;

	sreq->len = min(sreq->len, rsize);
	return true;
}

static void nfs_netfs_issue_read(struct netfs_io_subrequest *sreq)
{
	struct nfs_netfs_io_data	*netfs;
	struct nfs_pageio_descriptor	pgio;
	struct inode *inode = sreq->rreq->inode;
	struct nfs_open_context *ctx = sreq->rreq->netfs_priv;
	struct page *page;
	int err;
	pgoff_t start = (sreq->start + sreq->transferred) >> PAGE_SHIFT;
	pgoff_t last = ((sreq->start + sreq->len -
			 sreq->transferred - 1) >> PAGE_SHIFT);
	XA_STATE(xas, &sreq->rreq->mapping->i_pages, start);

	nfs_pageio_init_read(&pgio, inode, false,
			     &nfs_async_read_completion_ops);

	netfs = nfs_netfs_alloc(sreq);
	if (!netfs)
		return netfs_subreq_terminated(sreq, -ENOMEM, false);

	pgio.pg_netfs = netfs; /* used in completion */

	xas_lock(&xas);
	xas_for_each(&xas, page, last) {
		/* nfs_read_add_folio() may schedule() due to pNFS layout and other RPCs  */
		xas_pause(&xas);
		xas_unlock(&xas);
		err = nfs_read_add_folio(&pgio, ctx, page_folio(page));
		if (err < 0) {
			netfs->error = err;
			goto out;
		}
		xas_lock(&xas);
	}
	xas_unlock(&xas);
out:
	nfs_pageio_complete_read(&pgio);
	nfs_netfs_put(netfs);
}

void nfs_netfs_initiate_read(struct nfs_pgio_header *hdr)
{
	struct nfs_netfs_io_data        *netfs = hdr->netfs;

	if (!netfs)
		return;

	nfs_netfs_get(netfs);
}

int nfs_netfs_folio_unlock(struct folio *folio)
{
	struct inode *inode = folio_file_mapping(folio)->host;

	/*
	 * If fscache is enabled, netfs will unlock pages.
	 */
	if (netfs_inode(inode)->cache)
		return 0;

	return 1;
}

void nfs_netfs_read_completion(struct nfs_pgio_header *hdr)
{
	struct nfs_netfs_io_data        *netfs = hdr->netfs;
	struct netfs_io_subrequest      *sreq;

	if (!netfs)
		return;

	sreq = netfs->sreq;
	if (test_bit(NFS_IOHDR_EOF, &hdr->flags))
		__set_bit(NETFS_SREQ_CLEAR_TAIL, &sreq->flags);

	if (hdr->error)
		netfs->error = hdr->error;
	else
		atomic64_add(hdr->res.count, &netfs->transferred);

	nfs_netfs_put(netfs);
	hdr->netfs = NULL;
}

const struct netfs_request_ops nfs_netfs_ops = {
	.init_request		= nfs_netfs_init_request,
	.free_request		= nfs_netfs_free_request,
	.begin_cache_operation	= nfs_netfs_begin_cache_operation,
	.issue_read		= nfs_netfs_issue_read,
	.clamp_length		= nfs_netfs_clamp_length
};
Commit	Line	Data
b4d0d230	1	// SPDX-License-Identifier: GPL-2.0-or-later
14727281 DH	2	/* NFS filesystem cache interface
	3	*
	4	* Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.
	5	* Written by David Howells (dhowells@redhat.com)
14727281 DH	6	*/
	7
	8	#include <linux/init.h>
	9	#include <linux/kernel.h>
	10	#include <linux/sched.h>
	11	#include <linux/mm.h>
	12	#include <linux/nfs_fs.h>
	13	#include <linux/nfs_fs_sb.h>
	14	#include <linux/in6.h>
	15	#include <linux/seq_file.h>
5a0e3ad6	16	#include <linux/slab.h>
402cb8dd	17	#include <linux/iversion.h>
000dbe0b DW	18	#include <linux/xarray.h>
	19	#include <linux/fscache.h>
	20	#include <linux/netfs.h>
14727281 DH	21
14727281 DH	22	#include "internal.h"
545db45f	23	#include "iostat.h"
14727281	24	#include "fscache.h"
e3f0a7fe	25	#include "nfstrace.h"
14727281	26
a6b5a28e	27	#define NFS_MAX_KEY_LEN 1000
08734048	28
a6b5a28e DW	29	static bool nfs_append_int(char key, int _len, unsigned long long x)
	30	{
	31	if (*_len > NFS_MAX_KEY_LEN)
	32	return false;
	33	if (x == 0)
	34	key[(*_len)++] = ',';
	35	else
	36	_len += sprintf(key + _len, ",%llx", x);
	37	return true;
	38	}
402cb8dd	39
14727281 DH	40	/*
	41	* Get the per-client index cookie for an NFS client if the appropriate mount
	42	* flag was set
	43	* - We always try and get an index cookie for the client, but get filehandle
	44	* cookies on a per-superblock basis, depending on the mount flags
	45	*/
a6b5a28e DW	46	static bool nfs_fscache_get_client_key(struct nfs_client *clp,
a6b5a28e DW	47	char key, int _len)
14727281	48	{
402cb8dd DH	49	const struct sockaddr_in6 sin6 = (struct sockaddr_in6 ) &clp->cl_addr;
402cb8dd DH	50	const struct sockaddr_in sin = (struct sockaddr_in ) &clp->cl_addr;
402cb8dd	51
a6b5a28e DW	52	_len += snprintf(key + _len, NFS_MAX_KEY_LEN - *_len,
	53	",%u.%u,%x",
	54	clp->rpc_ops->version,
	55	clp->cl_minorversion,
	56	clp->cl_addr.ss_family);
402cb8dd DH	57
	58	switch (clp->cl_addr.ss_family) {
	59	case AF_INET:
a6b5a28e DW	60	if (!nfs_append_int(key, _len, sin->sin_port) \|\|
	61	!nfs_append_int(key, _len, sin->sin_addr.s_addr))
	62	return false;
	63	return true;
402cb8dd DH	64
402cb8dd DH	65	case AF_INET6:
a6b5a28e DW	66	if (!nfs_append_int(key, _len, sin6->sin6_port) \|\|
	67	!nfs_append_int(key, _len, sin6->sin6_addr.s6_addr32[0]) \|\|
	68	!nfs_append_int(key, _len, sin6->sin6_addr.s6_addr32[1]) \|\|
	69	!nfs_append_int(key, _len, sin6->sin6_addr.s6_addr32[2]) \|\|
	70	!nfs_append_int(key, _len, sin6->sin6_addr.s6_addr32[3]))
	71	return false;
	72	return true;
402cb8dd DH	73
	74	default:
	75	printk(KERN_WARNING "NFS: Unknown network family '%d'\n",
	76	clp->cl_addr.ss_family);
a6b5a28e	77	return false;
402cb8dd	78	}
14727281	79	}
08734048 DH	80
08734048 DH	81	/*
a6b5a28e	82	* Get the cache cookie for an NFS superblock.
2df54806 DH	83	*
	84	* The default uniquifier is just an empty string, but it may be overridden
	85	* either by the 'fsc=xxx' option to mount, or by inheriting it from the parent
	86	* superblock across an automount point of some nature.
08734048	87	*/
a6b5a28e	88	int nfs_fscache_get_super_cookie(struct super_block sb, const char uniq, int ulen)
08734048	89	{
a6b5a28e	90	struct fscache_volume *vcookie;
08734048	91	struct nfs_server *nfss = NFS_SB(sb);
a6b5a28e DW	92	unsigned int len = 3;
a6b5a28e DW	93	char *key;
2df54806	94
a6b5a28e DW	95	if (uniq) {
	96	nfss->fscache_uniq = kmemdup_nul(uniq, ulen, GFP_KERNEL);
	97	if (!nfss->fscache_uniq)
	98	return -ENOMEM;
2df54806 DH	99	}
2df54806 DH	100
a6b5a28e	101	key = kmalloc(NFS_MAX_KEY_LEN + 24, GFP_KERNEL);
08734048	102	if (!key)
a6b5a28e DW	103	return -ENOMEM;
	104
	105	memcpy(key, "nfs", 3);
	106	if (!nfs_fscache_get_client_key(nfss->nfs_client, key, &len) \|\|
	107	!nfs_append_int(key, &len, nfss->fsid.major) \|\|
	108	!nfs_append_int(key, &len, nfss->fsid.minor) \|\|
	109	!nfs_append_int(key, &len, sb->s_flags & NFS_SB_MASK) \|\|
	110	!nfs_append_int(key, &len, nfss->flags) \|\|
	111	!nfs_append_int(key, &len, nfss->rsize) \|\|
	112	!nfs_append_int(key, &len, nfss->wsize) \|\|
	113	!nfs_append_int(key, &len, nfss->acregmin) \|\|
	114	!nfs_append_int(key, &len, nfss->acregmax) \|\|
	115	!nfs_append_int(key, &len, nfss->acdirmin) \|\|
	116	!nfs_append_int(key, &len, nfss->acdirmax) \|\|
	117	!nfs_append_int(key, &len, nfss->client->cl_auth->au_flavor))
	118	goto out;
	119
	120	if (ulen > 0) {
	121	if (ulen > NFS_MAX_KEY_LEN - len)
	122	goto out;
	123	key[len++] = ',';
	124	memcpy(key + len, uniq, ulen);
	125	len += ulen;
08734048	126	}
a6b5a28e	127	key[len] = 0;
08734048 DH	128
08734048 DH	129	/* create a cache index for looking up filehandles */
a6b5a28e DW	130	vcookie = fscache_acquire_volume(key,
	131	NULL, /* preferred_cache */
	132	NULL, 0 /* coherency_data */);
a6b5a28e DW	133	if (IS_ERR(vcookie)) {
	134	if (vcookie != ERR_PTR(-EBUSY)) {
	135	kfree(key);
	136	return PTR_ERR(vcookie);
	137	}
	138	pr_err("NFS: Cache volume key already in use (%s)\n", key);
	139	vcookie = NULL;
	140	}
	141	nfss->fscache = vcookie;
08734048	142
a6b5a28e	143	out:
08734048	144	kfree(key);
a6b5a28e	145	return 0;
08734048 DH	146	}
	147
	148	/*
	149	* release a per-superblock cookie
	150	*/
	151	void nfs_fscache_release_super_cookie(struct super_block *sb)
	152	{
	153	struct nfs_server *nfss = NFS_SB(sb);
	154
a6b5a28e	155	fscache_relinquish_volume(nfss->fscache, NULL, false);
08734048	156	nfss->fscache = NULL;
a6b5a28e	157	kfree(nfss->fscache_uniq);
50eaa652 DW	158	}
50eaa652 DW	159
ef79c097 DH	160	/*
	161	* Initialise the per-inode cache cookie pointer for an NFS inode.
	162	*/
f1fe29b4	163	void nfs_fscache_init_inode(struct inode *inode)
ef79c097	164	{
402cb8dd	165	struct nfs_fscache_inode_auxdata auxdata;
dea1bb35	166	struct nfs_server *nfss = NFS_SERVER(inode);
ef79c097 DH	167	struct nfs_inode *nfsi = NFS_I(inode);
ef79c097 DH	168
88a4d7bd	169	netfs_inode(inode)->cache = NULL;
dea1bb35	170	if (!(nfss->fscache && S_ISREG(inode->i_mode)))
ef79c097	171	return;
402cb8dd	172
45f3a70b	173	nfs_fscache_update_auxdata(&auxdata, inode);
402cb8dd	174
88a4d7bd DW	175	netfs_inode(inode)->cache = fscache_acquire_cookie(
88a4d7bd DW	176	nfss->fscache,
a6b5a28e DW	177	0,
	178	nfsi->fh.data, /* index_key */
	179	nfsi->fh.size,
	180	&auxdata, /* aux_data */
	181	sizeof(auxdata),
45f3a70b	182	i_size_read(inode));
ef79c097 DH	183	}
	184
	185	/*
	186	* Release a per-inode cookie.
	187	*/
f1fe29b4	188	void nfs_fscache_clear_inode(struct inode *inode)
ef79c097	189	{
88a4d7bd DW	190	fscache_relinquish_cookie(netfs_i_cookie(netfs_inode(inode)), false);
88a4d7bd DW	191	netfs_inode(inode)->cache = NULL;
ef79c097 DH	192	}
ef79c097 DH	193
ef79c097	194	/*
f1fe29b4 DH	195	* Enable or disable caching for a file that is being opened as appropriate.
	196	* The cookie is allocated when the inode is initialised, but is not enabled at
	197	* that time. Enablement is deferred to file-open time to avoid stat() and
	198	* access() thrashing the cache.
	199	*
	200	* For now, with NFS, only regular files that are open read-only will be able
	201	* to use the cache.
	202	*
	203	* We enable the cache for an inode if we open it read-only and it isn't
	204	* currently open for writing. We disable the cache if the inode is open
	205	* write-only.
	206	*
	207	* The caller uses the file struct to pin i_writecount on the inode before
	208	* calling us when a file is opened for writing, so we can make use of that.
	209	*
	210	* Note that this may be invoked multiple times in parallel by parallel
	211	* nfs_open() functions.
ef79c097	212	*/
f1fe29b4	213	void nfs_fscache_open_file(struct inode inode, struct file filp)
ef79c097	214	{
402cb8dd	215	struct nfs_fscache_inode_auxdata auxdata;
88a4d7bd	216	struct fscache_cookie *cookie = netfs_i_cookie(netfs_inode(inode));
a6b5a28e	217	bool open_for_write = inode_is_open_for_write(inode);
ef79c097	218
f1fe29b4 DH	219	if (!fscache_cookie_valid(cookie))
f1fe29b4 DH	220	return;
ef79c097	221
a6b5a28e DW	222	fscache_use_cookie(cookie, open_for_write);
a6b5a28e DW	223	if (open_for_write) {
45f3a70b	224	nfs_fscache_update_auxdata(&auxdata, inode);
a6b5a28e DW	225	fscache_invalidate(cookie, &auxdata, i_size_read(inode),
a6b5a28e DW	226	FSCACHE_INVAL_DIO_WRITE);
ef79c097	227	}
ef79c097	228	}
f1fe29b4	229	EXPORT_SYMBOL_GPL(nfs_fscache_open_file);
545db45f	230
a6b5a28e	231	void nfs_fscache_release_file(struct inode inode, struct file filp)
545db45f	232	{
a6b5a28e	233	struct nfs_fscache_inode_auxdata auxdata;
88a4d7bd	234	struct fscache_cookie *cookie = netfs_i_cookie(netfs_inode(inode));
9c4a5c75	235	loff_t i_size = i_size_read(inode);
545db45f	236
9c4a5c75 DW	237	nfs_fscache_update_auxdata(&auxdata, inode);
9c4a5c75 DW	238	fscache_unuse_cookie(cookie, &auxdata, &i_size);
9a9fc1c0 DH	239	}
9a9fc1c0 DH	240
000dbe0b	241	int nfs_netfs_read_folio(struct file file, struct folio folio)
16f2f4e6	242	{
000dbe0b DW	243	if (!netfs_inode(folio_inode(folio))->cache)
	244	return -ENOBUFS;
	245
	246	return netfs_read_folio(file, folio);
16f2f4e6 DH	247	}
16f2f4e6 DH	248
000dbe0b	249	int nfs_netfs_readahead(struct readahead_control *ractl)
16f2f4e6	250	{
000dbe0b DW	251	struct inode *inode = ractl->mapping->host;
	252
	253	if (!netfs_inode(inode)->cache)
	254	return -ENOBUFS;
	255
	256	netfs_readahead(ractl);
	257	return 0;
16f2f4e6 DH	258	}
16f2f4e6 DH	259
c5733ae6	260	static atomic_t nfs_netfs_debug_id;
000dbe0b	261	static int nfs_netfs_init_request(struct netfs_io_request rreq, struct file file)
9a9fc1c0	262	{
000dbe0b DW	263	rreq->netfs_priv = get_nfs_open_context(nfs_file_open_context(file));
000dbe0b DW	264	rreq->debug_id = atomic_inc_return(&nfs_netfs_debug_id);
16f2f4e6	265
000dbe0b DW	266	return 0;
000dbe0b DW	267	}
ba512c1b	268
000dbe0b DW	269	static void nfs_netfs_free_request(struct netfs_io_request *rreq)
	270	{
	271	put_nfs_open_context(rreq->netfs_priv);
	272	}
9a9fc1c0	273
000dbe0b DW	274	static inline int nfs_netfs_begin_cache_operation(struct netfs_io_request *rreq)
	275	{
	276	return fscache_begin_read_operation(&rreq->cache_resources,
	277	netfs_i_cookie(netfs_inode(rreq->inode)));
9a9fc1c0	278	}
7f8e05f6	279
000dbe0b	280	static struct nfs_netfs_io_data nfs_netfs_alloc(struct netfs_io_subrequest sreq)
7f8e05f6	281	{
000dbe0b DW	282	struct nfs_netfs_io_data *netfs;
	283
	284	netfs = kzalloc(sizeof(*netfs), GFP_KERNEL_ACCOUNT);
	285	if (!netfs)
	286	return NULL;
	287	netfs->sreq = sreq;
	288	refcount_set(&netfs->refcount, 1);
	289	return netfs;
	290	}
16f2f4e6	291
000dbe0b DW	292	static bool nfs_netfs_clamp_length(struct netfs_io_subrequest *sreq)
	293	{
	294	size_t rsize = NFS_SB(sreq->rreq->inode->i_sb)->rsize;
7f8e05f6	295
000dbe0b DW	296	sreq->len = min(sreq->len, rsize);
	297	return true;
	298	}
16f2f4e6	299
000dbe0b DW	300	static void nfs_netfs_issue_read(struct netfs_io_subrequest *sreq)
	301	{
	302	struct nfs_netfs_io_data *netfs;
	303	struct nfs_pageio_descriptor pgio;
	304	struct inode *inode = sreq->rreq->inode;
	305	struct nfs_open_context *ctx = sreq->rreq->netfs_priv;
	306	struct page *page;
	307	int err;
	308	pgoff_t start = (sreq->start + sreq->transferred) >> PAGE_SHIFT;
	309	pgoff_t last = ((sreq->start + sreq->len -
	310	sreq->transferred - 1) >> PAGE_SHIFT);
	311	XA_STATE(xas, &sreq->rreq->mapping->i_pages, start);
	312
	313	nfs_pageio_init_read(&pgio, inode, false,
	314	&nfs_async_read_completion_ops);
	315
	316	netfs = nfs_netfs_alloc(sreq);
	317	if (!netfs)
	318	return netfs_subreq_terminated(sreq, -ENOMEM, false);
	319
	320	pgio.pg_netfs = netfs; /* used in completion */
	321
	322	xas_lock(&xas);
	323	xas_for_each(&xas, page, last) {
	324	/* nfs_read_add_folio() may schedule() due to pNFS layout and other RPCs */
	325	xas_pause(&xas);
	326	xas_unlock(&xas);
	327	err = nfs_read_add_folio(&pgio, ctx, page_folio(page));
	328	if (err < 0) {
	329	netfs->error = err;
	330	goto out;
	331	}
	332	xas_lock(&xas);
16f2f4e6	333	}
000dbe0b DW	334	xas_unlock(&xas);
	335	out:
	336	nfs_pageio_complete_read(&pgio);
	337	nfs_netfs_put(netfs);
7f8e05f6	338	}
000dbe0b DW	339
	340	void nfs_netfs_initiate_read(struct nfs_pgio_header *hdr)
	341	{
	342	struct nfs_netfs_io_data *netfs = hdr->netfs;
	343
	344	if (!netfs)
	345	return;
	346
	347	nfs_netfs_get(netfs);
	348	}
	349
	350	int nfs_netfs_folio_unlock(struct folio *folio)
	351	{
	352	struct inode *inode = folio_file_mapping(folio)->host;
	353
	354	/*
	355	* If fscache is enabled, netfs will unlock pages.
	356	*/
	357	if (netfs_inode(inode)->cache)
	358	return 0;
	359
	360	return 1;
	361	}
	362
	363	void nfs_netfs_read_completion(struct nfs_pgio_header *hdr)
	364	{
	365	struct nfs_netfs_io_data *netfs = hdr->netfs;
	366	struct netfs_io_subrequest *sreq;
	367
	368	if (!netfs)
	369	return;
	370
	371	sreq = netfs->sreq;
	372	if (test_bit(NFS_IOHDR_EOF, &hdr->flags))
	373	__set_bit(NETFS_SREQ_CLEAR_TAIL, &sreq->flags);
	374
	375	if (hdr->error)
	376	netfs->error = hdr->error;
	377	else
	378	atomic64_add(hdr->res.count, &netfs->transferred);
	379
	380	nfs_netfs_put(netfs);
	381	hdr->netfs = NULL;
	382	}
	383
	384	const struct netfs_request_ops nfs_netfs_ops = {
	385	.init_request = nfs_netfs_init_request,
	386	.free_request = nfs_netfs_free_request,
	387	.begin_cache_operation = nfs_netfs_begin_cache_operation,
	388	.issue_read = nfs_netfs_issue_read,
	389	.clamp_length = nfs_netfs_clamp_length
	390	};