1 files changed, 55 insertions, 392 deletions

diff --git a/fs/ceph/cache.c b/fs/ceph/cache.c
index fd1172823f86..f678bab189d8 100644
--- a/fs/ceph/cache.c
+++ b/fs/ceph/cache.c
@@ -1,449 +1,112 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * Ceph cache definitions.
  *
  *  Copyright (C) 2013 by Adfin Solutions, Inc. All Rights Reserved.
  *  Written by Milosz Tanski (milosz@adfin.com)
- *
- *  This program is free software; you can redistribute it and/or modify
- *  it under the terms of the GNU General Public License version 2
- *  as published by the Free Software Foundation.
- *
- *  This program is distributed in the hope that it will be useful,
- *  but WITHOUT ANY WARRANTY; without even the implied warranty of
- *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- *  GNU General Public License for more details.
- *
- *  You should have received a copy of the GNU General Public License
- *  along with this program; if not, write to:
- *  Free Software Foundation
- *  51 Franklin Street, Fifth Floor
- *  Boston, MA  02111-1301  USA
- *
  */
 
+#include <linux/ceph/ceph_debug.h>
+
+#include <linux/fs_context.h>
 #include "super.h"
 #include "cache.h"
 
-struct ceph_aux_inode {
-	u64 		version;
-	struct timespec	mtime;
-	loff_t          size;
-};
-
-struct fscache_netfs ceph_cache_netfs = {
-	.name		= "ceph",
-	.version	= 0,
-};
-
-static DEFINE_MUTEX(ceph_fscache_lock);
-static LIST_HEAD(ceph_fscache_list);
-
-struct ceph_fscache_entry {
-	struct list_head list;
-	struct fscache_cookie *fscache;
-	struct ceph_fsid fsid;
-	size_t uniq_len;
-	char uniquifier[0];
-};
-
-static uint16_t ceph_fscache_session_get_key(const void *cookie_netfs_data,
-					     void *buffer, uint16_t maxbuf)
-{
-	const struct ceph_fs_client* fsc = cookie_netfs_data;
-	const char *fscache_uniq = fsc->mount_options->fscache_uniq;
-	uint16_t fsid_len, uniq_len;
-
-	fsid_len = sizeof(fsc->client->fsid);
-	uniq_len = fscache_uniq ? strlen(fscache_uniq) : 0;
-	if (fsid_len + uniq_len > maxbuf)
-		return 0;
-
-	memcpy(buffer, &fsc->client->fsid, fsid_len);
-	if (uniq_len)
-		memcpy(buffer + fsid_len, fscache_uniq, uniq_len);
-
-	return fsid_len + uniq_len;
-}
-
-static const struct fscache_cookie_def ceph_fscache_fsid_object_def = {
-	.name		= "CEPH.fsid",
-	.type		= FSCACHE_COOKIE_TYPE_INDEX,
-	.get_key	= ceph_fscache_session_get_key,
-};
-
-int ceph_fscache_register(void)
-{
-	return fscache_register_netfs(&ceph_cache_netfs);
-}
-
-void ceph_fscache_unregister(void)
-{
-	fscache_unregister_netfs(&ceph_cache_netfs);
-}
-
-int ceph_fscache_register_fs(struct ceph_fs_client* fsc)
-{
-	const struct ceph_fsid *fsid = &fsc->client->fsid;
-	const char *fscache_uniq = fsc->mount_options->fscache_uniq;
-	size_t uniq_len = fscache_uniq ? strlen(fscache_uniq) : 0;
-	struct ceph_fscache_entry *ent;
-	int err = 0;
-
-	mutex_lock(&ceph_fscache_lock);
-	list_for_each_entry(ent, &ceph_fscache_list, list) {
-		if (memcmp(&ent->fsid, fsid, sizeof(*fsid)))
-			continue;
-		if (ent->uniq_len != uniq_len)
-			continue;
-		if (uniq_len && memcmp(ent->uniquifier, fscache_uniq, uniq_len))
-			continue;
-
-		pr_err("fscache cookie already registered for fsid %pU\n", fsid);
-		pr_err("  use fsc=%%s mount option to specify a uniquifier\n");
-		err = -EBUSY;
-		goto out_unlock;
-	}
-
-	ent = kzalloc(sizeof(*ent) + uniq_len, GFP_KERNEL);
-	if (!ent) {
-		err = -ENOMEM;
-		goto out_unlock;
-	}
-
-	fsc->fscache = fscache_acquire_cookie(ceph_cache_netfs.primary_index,
-					      &ceph_fscache_fsid_object_def,
-					      fsc, true);
-
-	if (fsc->fscache) {
-		memcpy(&ent->fsid, fsid, sizeof(*fsid));
-		if (uniq_len > 0) {
-			memcpy(&ent->uniquifier, fscache_uniq, uniq_len);
-			ent->uniq_len = uniq_len;
-		}
-		ent->fscache = fsc->fscache;
-		list_add_tail(&ent->list, &ceph_fscache_list);
-	} else {
-		kfree(ent);
-		pr_err("unable to register fscache cookie for fsid %pU\n",
-		       fsid);
-		/* all other fs ignore this error */
-	}
-out_unlock:
-	mutex_unlock(&ceph_fscache_lock);
-	return err;
-}
-
-static uint16_t ceph_fscache_inode_get_key(const void *cookie_netfs_data,
-					   void *buffer, uint16_t maxbuf)
-{
-	const struct ceph_inode_info* ci = cookie_netfs_data;
-	uint16_t klen;
-
-	/* use ceph virtual inode (id + snapshot) */
-	klen = sizeof(ci->i_vino);
-	if (klen > maxbuf)
-		return 0;
-
-	memcpy(buffer, &ci->i_vino, klen);
-	return klen;
-}
-
-static uint16_t ceph_fscache_inode_get_aux(const void *cookie_netfs_data,
-					   void *buffer, uint16_t bufmax)
-{
-	struct ceph_aux_inode aux;
-	const struct ceph_inode_info* ci = cookie_netfs_data;
-	const struct inode* inode = &ci->vfs_inode;
-
-	memset(&aux, 0, sizeof(aux));
-	aux.version = ci->i_version;
-	aux.mtime = inode->i_mtime;
-	aux.size = i_size_read(inode);
-
-	memcpy(buffer, &aux, sizeof(aux));
-
-	return sizeof(aux);
-}
-
-static void ceph_fscache_inode_get_attr(const void *cookie_netfs_data,
-					uint64_t *size)
-{
-	const struct ceph_inode_info* ci = cookie_netfs_data;
-	*size = i_size_read(&ci->vfs_inode);
-}
-
-static enum fscache_checkaux ceph_fscache_inode_check_aux(
-	void *cookie_netfs_data, const void *data, uint16_t dlen)
-{
-	struct ceph_aux_inode aux;
-	struct ceph_inode_info* ci = cookie_netfs_data;
-	struct inode* inode = &ci->vfs_inode;
-
-	if (dlen != sizeof(aux))
-		return FSCACHE_CHECKAUX_OBSOLETE;
-
-	memset(&aux, 0, sizeof(aux));
-	aux.version = ci->i_version;
-	aux.mtime = inode->i_mtime;
-	aux.size = i_size_read(inode);
-
-	if (memcmp(data, &aux, sizeof(aux)) != 0)
-		return FSCACHE_CHECKAUX_OBSOLETE;
-
-	dout("ceph inode 0x%p cached okay", ci);
-	return FSCACHE_CHECKAUX_OKAY;
-}
-
-static void ceph_fscache_inode_now_uncached(void* cookie_netfs_data)
-{
-	struct ceph_inode_info* ci = cookie_netfs_data;
-	struct pagevec pvec;
-	pgoff_t first;
-	int loop, nr_pages;
-
-	pagevec_init(&pvec, 0);
-	first = 0;
-
-	dout("ceph inode 0x%p now uncached", ci);
-
-	while (1) {
-		nr_pages = pagevec_lookup(&pvec, ci->vfs_inode.i_mapping, first,
-					  PAGEVEC_SIZE - pagevec_count(&pvec));
-
-		if (!nr_pages)
-			break;
-
-		for (loop = 0; loop < nr_pages; loop++)
-			ClearPageFsCache(pvec.pages[loop]);
-
-		first = pvec.pages[nr_pages - 1]->index + 1;
-
-		pvec.nr = nr_pages;
-		pagevec_release(&pvec);
-		cond_resched();
-	}
-}
-
-static const struct fscache_cookie_def ceph_fscache_inode_object_def = {
-	.name		= "CEPH.inode",
-	.type		= FSCACHE_COOKIE_TYPE_DATAFILE,
-	.get_key	= ceph_fscache_inode_get_key,
-	.get_attr	= ceph_fscache_inode_get_attr,
-	.get_aux	= ceph_fscache_inode_get_aux,
-	.check_aux	= ceph_fscache_inode_check_aux,
-	.now_uncached	= ceph_fscache_inode_now_uncached,
-};
-
 void ceph_fscache_register_inode_cookie(struct inode *inode)
 {
 	struct ceph_inode_info *ci = ceph_inode(inode);
-	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
+	struct ceph_fs_client *fsc = ceph_inode_to_fs_client(inode);
 
-	/* No caching for filesystem */
-	if (fsc->fscache == NULL)
+	/* No caching for filesystem? */
+	if (!fsc->fscache)
 		return;
 
-	/* Only cache for regular files that are read only */
+	/* Regular files only */
 	if (!S_ISREG(inode->i_mode))
 		return;
 
-	inode_lock_nested(inode, I_MUTEX_CHILD);
-	if (!ci->fscache) {
-		ci->fscache = fscache_acquire_cookie(fsc->fscache,
-					&ceph_fscache_inode_object_def,
-					ci, false);
-	}
-	inode_unlock(inode);
-}
-
-void ceph_fscache_unregister_inode_cookie(struct ceph_inode_info* ci)
-{
-	struct fscache_cookie* cookie;
-
-	if ((cookie = ci->fscache) == NULL)
+	/* Only new inodes! */
+	if (!(inode_state_read_once(inode) & I_NEW))
 		return;
 
-	ci->fscache = NULL;
+	WARN_ON_ONCE(ci->netfs.cache);
 
-	fscache_uncache_all_inode_pages(cookie, &ci->vfs_inode);
-	fscache_relinquish_cookie(cookie, 0);
+	ci->netfs.cache =
+		fscache_acquire_cookie(fsc->fscache, 0,
+				       &ci->i_vino, sizeof(ci->i_vino),
+				       &ci->i_version, sizeof(ci->i_version),
+				       i_size_read(inode));
+	if (ci->netfs.cache)
+		mapping_set_release_always(inode->i_mapping);
 }
 
-static bool ceph_fscache_can_enable(void *data)
+void ceph_fscache_unregister_inode_cookie(struct ceph_inode_info *ci)
 {
-	struct inode *inode = data;
-	return !inode_is_open_for_write(inode);
+	fscache_relinquish_cookie(ceph_fscache_cookie(ci), false);
 }
 
-void ceph_fscache_file_set_cookie(struct inode *inode, struct file *filp)
+void ceph_fscache_use_cookie(struct inode *inode, bool will_modify)
 {
 	struct ceph_inode_info *ci = ceph_inode(inode);
 
-	if (!fscache_cookie_valid(ci->fscache))
-		return;
-
-	if (inode_is_open_for_write(inode)) {
-		dout("fscache_file_set_cookie %p %p disabling cache\n",
-		     inode, filp);
-		fscache_disable_cookie(ci->fscache, false);
-		fscache_uncache_all_inode_pages(ci->fscache, inode);
-	} else {
-		fscache_enable_cookie(ci->fscache, ceph_fscache_can_enable,
-				inode);
-		if (fscache_cookie_enabled(ci->fscache)) {
-			dout("fscache_file_set_cookie %p %p enabling cache\n",
-			     inode, filp);
-		}
-	}
+	fscache_use_cookie(ceph_fscache_cookie(ci), will_modify);
 }
 
-static void ceph_vfs_readpage_complete(struct page *page, void *data, int error)
-{
-	if (!error)
-		SetPageUptodate(page);
-}
-
-static void ceph_vfs_readpage_complete_unlock(struct page *page, void *data, int error)
-{
-	if (!error)
-		SetPageUptodate(page);
-
-	unlock_page(page);
-}
-
-static inline bool cache_valid(struct ceph_inode_info *ci)
-{
-	return ci->i_fscache_gen == ci->i_rdcache_gen;
-}
-
-
-/* Atempt to read from the fscache,
- *
- * This function is called from the readpage_nounlock context. DO NOT attempt to
- * unlock the page here (or in the callback).
- */
-int ceph_readpage_from_fscache(struct inode *inode, struct page *page)
+void ceph_fscache_unuse_cookie(struct inode *inode, bool update)
 {
 	struct ceph_inode_info *ci = ceph_inode(inode);
-	int ret;
-
-	if (!cache_valid(ci))
-		return -ENOBUFS;
-
-	ret = fscache_read_or_alloc_page(ci->fscache, page,
-					 ceph_vfs_readpage_complete, NULL,
-					 GFP_KERNEL);
 
-	switch (ret) {
-		case 0: /* Page found */
-			dout("page read submitted\n");
-			return 0;
-		case -ENOBUFS: /* Pages were not found, and can't be */
-		case -ENODATA: /* Pages were not found */
-			dout("page/inode not in cache\n");
-			return ret;
-		default:
-			dout("%s: unknown error ret = %i\n", __func__, ret);
-			return ret;
-	}
-}
+	if (update) {
+		loff_t i_size = i_size_read(inode);
 
-int ceph_readpages_from_fscache(struct inode *inode,
-				  struct address_space *mapping,
-				  struct list_head *pages,
-				  unsigned *nr_pages)
-{
-	struct ceph_inode_info *ci = ceph_inode(inode);
-	int ret;
-
-	if (!cache_valid(ci))
-		return -ENOBUFS;
-
-	ret = fscache_read_or_alloc_pages(ci->fscache, mapping, pages, nr_pages,
-					  ceph_vfs_readpage_complete_unlock,
-					  NULL, mapping_gfp_mask(mapping));
-
-	switch (ret) {
-		case 0: /* All pages found */
-			dout("all-page read submitted\n");
-			return 0;
-		case -ENOBUFS: /* Some pages were not found, and can't be */
-		case -ENODATA: /* some pages were not found */
-			dout("page/inode not in cache\n");
-			return ret;
-		default:
-			dout("%s: unknown error ret = %i\n", __func__, ret);
-			return ret;
+		fscache_unuse_cookie(ceph_fscache_cookie(ci),
+				     &ci->i_version, &i_size);
+	} else {
+		fscache_unuse_cookie(ceph_fscache_cookie(ci), NULL, NULL);
 	}
 }
 
-void ceph_readpage_to_fscache(struct inode *inode, struct page *page)
+void ceph_fscache_update(struct inode *inode)
 {
 	struct ceph_inode_info *ci = ceph_inode(inode);
-	int ret;
-
-	if (!PageFsCache(page))
-		return;
-
-	if (!cache_valid(ci))
-		return;
+	loff_t i_size = i_size_read(inode);
 
-	ret = fscache_write_page(ci->fscache, page, GFP_KERNEL);
-	if (ret)
-		 fscache_uncache_page(ci->fscache, page);
+	fscache_update_cookie(ceph_fscache_cookie(ci), &ci->i_version, &i_size);
 }
 
-void ceph_invalidate_fscache_page(struct inode* inode, struct page *page)
+void ceph_fscache_invalidate(struct inode *inode, bool dio_write)
 {
 	struct ceph_inode_info *ci = ceph_inode(inode);
 
-	if (!PageFsCache(page))
-		return;
-
-	fscache_wait_on_page_write(ci->fscache, page);
-	fscache_uncache_page(ci->fscache, page);
+	fscache_invalidate(ceph_fscache_cookie(ci),
+			   &ci->i_version, i_size_read(inode),
+			   dio_write ? FSCACHE_INVAL_DIO_WRITE : 0);
 }
 
-void ceph_fscache_unregister_fs(struct ceph_fs_client* fsc)
+int ceph_fscache_register_fs(struct ceph_fs_client* fsc, struct fs_context *fc)
 {
-	if (fscache_cookie_valid(fsc->fscache)) {
-		struct ceph_fscache_entry *ent;
-		bool found = false;
+	const struct ceph_fsid *fsid = &fsc->client->fsid;
+	const char *fscache_uniq = fsc->mount_options->fscache_uniq;
+	size_t uniq_len = fscache_uniq ? strlen(fscache_uniq) : 0;
+	char *name;
+	int err = 0;
 
-		mutex_lock(&ceph_fscache_lock);
-		list_for_each_entry(ent, &ceph_fscache_list, list) {
-			if (ent->fscache == fsc->fscache) {
-				list_del(&ent->list);
-				kfree(ent);
-				found = true;
-				break;
-			}
-		}
-		WARN_ON_ONCE(!found);
-		mutex_unlock(&ceph_fscache_lock);
+	name = kasprintf(GFP_KERNEL, "ceph,%pU%s%s", fsid, uniq_len ? "," : "",
+			 uniq_len ? fscache_uniq : "");
+	if (!name)
+		return -ENOMEM;
 
-		__fscache_relinquish_cookie(fsc->fscache, 0);
+	fsc->fscache = fscache_acquire_volume(name, NULL, NULL, 0);
+	if (IS_ERR_OR_NULL(fsc->fscache)) {
+		errorfc(fc, "Unable to register fscache cookie for %s", name);
+		err = fsc->fscache ? PTR_ERR(fsc->fscache) : -EOPNOTSUPP;
+		fsc->fscache = NULL;
 	}
-	fsc->fscache = NULL;
+	kfree(name);
+	return err;
 }
 
-/*
- * caller should hold CEPH_CAP_FILE_{RD,CACHE}
- */
-void ceph_fscache_revalidate_cookie(struct ceph_inode_info *ci)
+void ceph_fscache_unregister_fs(struct ceph_fs_client* fsc)
 {
-	if (cache_valid(ci))
-		return;
-
-	/* resue i_truncate_mutex. There should be no pending
-	 * truncate while the caller holds CEPH_CAP_FILE_RD */
-	mutex_lock(&ci->i_truncate_mutex);
-	if (!cache_valid(ci)) {
-		if (fscache_check_consistency(ci->fscache))
-			fscache_invalidate(ci->fscache);
-		spin_lock(&ci->i_ceph_lock);
-		ci->i_fscache_gen = ci->i_rdcache_gen;
-		spin_unlock(&ci->i_ceph_lock);
-	}
-	mutex_unlock(&ci->i_truncate_mutex);
+	fscache_relinquish_volume(fsc->fscache, NULL, false);
 }