Merge tag 'fscache-next-20180406' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull fscache updates from David Howells:
 "Three patches that fix some of AFS's usage of fscache:

   (1) Need to invalidate the cache if a foreign data change is detected
       on the server.

   (2) Move the vnode ID uniquifier (equivalent to i_generation) from
       the auxiliary data to the index key to prevent a race between
       file delete and a subsequent file create seeing the same index
       key.

   (3) Need to retire cookies that correspond to files that we think got
       deleted on the server.

  Four patches to fix some things in fscache and cachefiles:

   (4) Fix a couple of checker warnings.

   (5) Correctly indicate to the end-of-operation callback whether an
       operation completed or was cancelled.

   (6) Add a check for multiple cookie relinquishment.

   (7) Fix a path through the asynchronous write that doesn't wake up a
       waiter for a page if the cache decides not to write that page,
       but discards it instead.

  A couple of patches to add tracepoints to fscache and cachefiles:

   (8) Add tracepoints for cookie operators, object state machine
       execution, cachefiles object management and cachefiles VFS
       operations.

   (9) Add tracepoints for fscache operation management and page
       wrangling.

  And then three development patches:

  (10) Attach the index key and auxiliary data to the cookie, pass this
       information through various fscache-netfs API functions and get
       rid of the callbacks to the netfs to get it.

       This means that the cache can get at this information, even if
       the netfs goes away. It also means that the cache can be lazy in
       updating the coherency data.

  (11) Pass the object data size through various fscache-netfs API
       rather than calling back to the netfs for it, and store the value
       in the object.

       This makes it easier to correctly resize the object, as the size
       is updated on writes to the cache, rather than calling back out
       to the netfs.

  (12) Maintain a catalogue of allocated cookies. This makes it possible
       to catch cookie collision up front rather than down in the bowels
       of the cache being run from a service thread from the object
       state machine.

       This will also make it possible in the future to reconnect to a
       cookie that's not gone dead yet because it's waiting for
       finalisation of the storage and also make it possible to bring
       cookies online if the cache is added after the cookie has been
       obtained"

* tag 'fscache-next-20180406' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  fscache: Maintain a catalogue of allocated cookies
  fscache: Pass object size in rather than calling back for it
  fscache: Attach the index key and aux data to the cookie
  fscache: Add more tracepoints
  fscache: Add tracepoints
  fscache: Fix hanging wait on page discarded by writeback
  fscache: Detect multiple relinquishment of a cookie
  fscache: Pass the correct cancelled indications to fscache_op_complete()
  fscache, cachefiles: Fix checker warnings
  afs: Be more aggressive in retiring cached vnodes
  afs: Use the vnode ID uniquifier in the cache key not the aux data
  afs: Invalidate cache on server data change

3 files changed, 97 insertions, 166 deletions

diff --git a/fs/nfs/fscache-index.c b/fs/nfs/fscache-index.c
index 0ee4b93d36ea..1c5d8d31fc0a 100644
--- a/fs/nfs/fscache-index.c
+++ b/fs/nfs/fscache-index.c
@@ -50,59 +50,6 @@ void nfs_fscache_unregister(void)
 }
 
 /*
- * Layout of the key for an NFS server cache object.
- */
-struct nfs_server_key {
-	uint16_t	nfsversion;		/* NFS protocol version */
-	uint16_t	family;			/* address family */
-	uint16_t	port;			/* IP port */
-	union {
-		struct in_addr	ipv4_addr;	/* IPv4 address */
-		struct in6_addr ipv6_addr;	/* IPv6 address */
-	} addr[0];
-};
-
-/*
- * Generate a key to describe a server in the main NFS index
- * - We return the length of the key, or 0 if we can't generate one
- */
-static uint16_t nfs_server_get_key(const void *cookie_netfs_data,
-				   void *buffer, uint16_t bufmax)
-{
-	const struct nfs_client *clp = cookie_netfs_data;
-	const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) &clp->cl_addr;
-	const struct sockaddr_in *sin = (struct sockaddr_in *) &clp->cl_addr;
-	struct nfs_server_key *key = buffer;
-	uint16_t len = sizeof(struct nfs_server_key);
-
-	memset(key, 0, len);
-	key->nfsversion = clp->rpc_ops->version;
-	key->family = clp->cl_addr.ss_family;
-
-	switch (clp->cl_addr.ss_family) {
-	case AF_INET:
-		key->port = sin->sin_port;
-		key->addr[0].ipv4_addr = sin->sin_addr;
-		len += sizeof(key->addr[0].ipv4_addr);
-		break;
-
-	case AF_INET6:
-		key->port = sin6->sin6_port;
-		key->addr[0].ipv6_addr = sin6->sin6_addr;
-		len += sizeof(key->addr[0].ipv6_addr);
-		break;
-
-	default:
-		printk(KERN_WARNING "NFS: Unknown network family '%d'\n",
-		       clp->cl_addr.ss_family);
-		len = 0;
-		break;
-	}
-
-	return len;
-}
-
-/*
  * Define the server object for FS-Cache.  This is used to describe a server
  * object to fscache_acquire_cookie().  It is keyed by the NFS protocol and
  * server address parameters.
@@ -110,33 +57,9 @@ static uint16_t nfs_server_get_key(const void *cookie_netfs_data,
 const struct fscache_cookie_def nfs_fscache_server_index_def = {
 	.name		= "NFS.server",
 	.type 		= FSCACHE_COOKIE_TYPE_INDEX,
-	.get_key	= nfs_server_get_key,
 };
 
 /*
- * Generate a key to describe a superblock key in the main NFS index
- */
-static uint16_t nfs_super_get_key(const void *cookie_netfs_data,
-				  void *buffer, uint16_t bufmax)
-{
-	const struct nfs_fscache_key *key;
-	const struct nfs_server *nfss = cookie_netfs_data;
-	uint16_t len;
-
-	key = nfss->fscache_key;
-	len = sizeof(key->key) + key->key.uniq_len;
-	if (len > bufmax) {
-		len = 0;
-	} else {
-		memcpy(buffer, &key->key, sizeof(key->key));
-		memcpy(buffer + sizeof(key->key),
-		       key->key.uniquifier, key->key.uniq_len);
-	}
-
-	return len;
-}
-
-/*
  * Define the superblock object for FS-Cache.  This is used to describe a
  * superblock object to fscache_acquire_cookie().  It is keyed by all the NFS
  * parameters that might cause a separate superblock.
@@ -144,84 +67,9 @@ static uint16_t nfs_super_get_key(const void *cookie_netfs_data,
 const struct fscache_cookie_def nfs_fscache_super_index_def = {
 	.name		= "NFS.super",
 	.type 		= FSCACHE_COOKIE_TYPE_INDEX,
-	.get_key	= nfs_super_get_key,
 };
 
 /*
- * Definition of the auxiliary data attached to NFS inode storage objects
- * within the cache.
- *
- * The contents of this struct are recorded in the on-disk local cache in the
- * auxiliary data attached to the data storage object backing an inode.  This
- * permits coherency to be managed when a new inode binds to an already extant
- * cache object.
- */
-struct nfs_fscache_inode_auxdata {
-	struct timespec	mtime;
-	struct timespec	ctime;
-	loff_t		size;
-	u64		change_attr;
-};
-
-/*
- * Generate a key to describe an NFS inode in an NFS server's index
- */
-static uint16_t nfs_fscache_inode_get_key(const void *cookie_netfs_data,
-					  void *buffer, uint16_t bufmax)
-{
-	const struct nfs_inode *nfsi = cookie_netfs_data;
-	uint16_t nsize;
-
-	/* use the inode's NFS filehandle as the key */
-	nsize = nfsi->fh.size;
-	memcpy(buffer, nfsi->fh.data, nsize);
-	return nsize;
-}
-
-/*
- * Get certain file attributes from the netfs data
- * - This function can be absent for an index
- * - Not permitted to return an error
- * - The netfs data from the cookie being used as the source is presented
- */
-static void nfs_fscache_inode_get_attr(const void *cookie_netfs_data,
-				       uint64_t *size)
-{
-	const struct nfs_inode *nfsi = cookie_netfs_data;
-
-	*size = nfsi->vfs_inode.i_size;
-}
-
-/*
- * Get the auxiliary data from netfs data
- * - This function can be absent if the index carries no state data
- * - Should store the auxiliary data in the buffer
- * - Should return the amount of amount stored
- * - Not permitted to return an error
- * - The netfs data from the cookie being used as the source is presented
- */
-static uint16_t nfs_fscache_inode_get_aux(const void *cookie_netfs_data,
-					  void *buffer, uint16_t bufmax)
-{
-	struct nfs_fscache_inode_auxdata auxdata;
-	const struct nfs_inode *nfsi = cookie_netfs_data;
-
-	memset(&auxdata, 0, sizeof(auxdata));
-	auxdata.size = nfsi->vfs_inode.i_size;
-	auxdata.mtime = nfsi->vfs_inode.i_mtime;
-	auxdata.ctime = nfsi->vfs_inode.i_ctime;
-
-	if (NFS_SERVER(&nfsi->vfs_inode)->nfs_client->rpc_ops->version == 4)
-		auxdata.change_attr = inode_peek_iversion_raw(&nfsi->vfs_inode);
-
-	if (bufmax > sizeof(auxdata))
-		bufmax = sizeof(auxdata);
-
-	memcpy(buffer, &auxdata, bufmax);
-	return bufmax;
-}
-
-/*
  * Consult the netfs about the state of an object
  * - This function can be absent if the index carries no state data
  * - The netfs data from the cookie being used as the target is
@@ -230,7 +78,8 @@ static uint16_t nfs_fscache_inode_get_aux(const void *cookie_netfs_data,
 static
 enum fscache_checkaux nfs_fscache_inode_check_aux(void *cookie_netfs_data,
 						  const void *data,
-						  uint16_t datalen)
+						  uint16_t datalen,
+						  loff_t object_size)
 {
 	struct nfs_fscache_inode_auxdata auxdata;
 	struct nfs_inode *nfsi = cookie_netfs_data;
@@ -239,7 +88,6 @@ enum fscache_checkaux nfs_fscache_inode_check_aux(void *cookie_netfs_data,
 		return FSCACHE_CHECKAUX_OBSOLETE;
 
 	memset(&auxdata, 0, sizeof(auxdata));
-	auxdata.size = nfsi->vfs_inode.i_size;
 	auxdata.mtime = nfsi->vfs_inode.i_mtime;
 	auxdata.ctime = nfsi->vfs_inode.i_ctime;
 
@@ -288,9 +136,6 @@ static void nfs_fh_put_context(void *cookie_netfs_data, void *context)
 const struct fscache_cookie_def nfs_fscache_inode_object_def = {
 	.name		= "NFS.fh",
 	.type		= FSCACHE_COOKIE_TYPE_DATAFILE,
-	.get_key	= nfs_fscache_inode_get_key,
-	.get_attr	= nfs_fscache_inode_get_attr,
-	.get_aux	= nfs_fscache_inode_get_aux,
 	.check_aux	= nfs_fscache_inode_check_aux,
 	.get_context	= nfs_fh_get_context,
 	.put_context	= nfs_fh_put_context,
diff --git a/fs/nfs/fscache.c b/fs/nfs/fscache.c
index d63bea8bbfbb..b55fc7920c3b 100644
--- a/fs/nfs/fscache.c
+++ b/fs/nfs/fscache.c
@@ -18,6 +18,7 @@
 #include <linux/in6.h>
 #include <linux/seq_file.h>
 #include <linux/slab.h>
+#include <linux/iversion.h>
 
 #include "internal.h"
 #include "iostat.h"
@@ -29,6 +30,21 @@ static struct rb_root nfs_fscache_keys = RB_ROOT;
 static DEFINE_SPINLOCK(nfs_fscache_keys_lock);
 
 /*
+ * Layout of the key for an NFS server cache object.
+ */
+struct nfs_server_key {
+	struct {
+		uint16_t	nfsversion;		/* NFS protocol version */
+		uint16_t	family;			/* address family */
+		__be16		port;			/* IP port */
+	} hdr;
+	union {
+		struct in_addr	ipv4_addr;	/* IPv4 address */
+		struct in6_addr ipv6_addr;	/* IPv6 address */
+	};
+} __packed;
+
+/*
  * 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
@@ -36,10 +52,41 @@ static DEFINE_SPINLOCK(nfs_fscache_keys_lock);
  */
 void nfs_fscache_get_client_cookie(struct nfs_client *clp)
 {
+	const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) &clp->cl_addr;
+	const struct sockaddr_in *sin = (struct sockaddr_in *) &clp->cl_addr;
+	struct nfs_server_key key;
+	uint16_t len = sizeof(key.hdr);
+
+	memset(&key, 0, sizeof(key));
+	key.hdr.nfsversion = clp->rpc_ops->version;
+	key.hdr.family = clp->cl_addr.ss_family;
+
+	switch (clp->cl_addr.ss_family) {
+	case AF_INET:
+		key.hdr.port = sin->sin_port;
+		key.ipv4_addr = sin->sin_addr;
+		len += sizeof(key.ipv4_addr);
+		break;
+
+	case AF_INET6:
+		key.hdr.port = sin6->sin6_port;
+		key.ipv6_addr = sin6->sin6_addr;
+		len += sizeof(key.ipv6_addr);
+		break;
+
+	default:
+		printk(KERN_WARNING "NFS: Unknown network family '%d'\n",
+		       clp->cl_addr.ss_family);
+		clp->fscache = NULL;
+		return;
+	}
+
 	/* create a cache index for looking up filehandles */
 	clp->fscache = fscache_acquire_cookie(nfs_fscache_netfs.primary_index,
 					      &nfs_fscache_server_index_def,
-					      clp, true);
+					      &key, len,
+					      NULL, 0,
+					      clp, 0, true);
 	dfprintk(FSCACHE, "NFS: get client cookie (0x%p/0x%p)\n",
 		 clp, clp->fscache);
 }
@@ -52,7 +99,7 @@ void nfs_fscache_release_client_cookie(struct nfs_client *clp)
 	dfprintk(FSCACHE, "NFS: releasing client cookie (0x%p/0x%p)\n",
 		 clp, clp->fscache);
 
-	fscache_relinquish_cookie(clp->fscache, 0);
+	fscache_relinquish_cookie(clp->fscache, NULL, false);
 	clp->fscache = NULL;
 }
 
@@ -139,7 +186,9 @@ void nfs_fscache_get_super_cookie(struct super_block *sb, const char *uniq, int
 	/* create a cache index for looking up filehandles */
 	nfss->fscache = fscache_acquire_cookie(nfss->nfs_client->fscache,
 					       &nfs_fscache_super_index_def,
-					       nfss, true);
+					       key, sizeof(*key) + ulen,
+					       NULL, 0,
+					       nfss, 0, true);
 	dfprintk(FSCACHE, "NFS: get superblock cookie (0x%p/0x%p)\n",
 		 nfss, nfss->fscache);
 	return;
@@ -163,7 +212,7 @@ void nfs_fscache_release_super_cookie(struct super_block *sb)
 	dfprintk(FSCACHE, "NFS: releasing superblock cookie (0x%p/0x%p)\n",
 		 nfss, nfss->fscache);
 
-	fscache_relinquish_cookie(nfss->fscache, 0);
+	fscache_relinquish_cookie(nfss->fscache, NULL, false);
 	nfss->fscache = NULL;
 
 	if (nfss->fscache_key) {
@@ -180,14 +229,25 @@ void nfs_fscache_release_super_cookie(struct super_block *sb)
  */
 void nfs_fscache_init_inode(struct inode *inode)
 {
+	struct nfs_fscache_inode_auxdata auxdata;
 	struct nfs_inode *nfsi = NFS_I(inode);
 
 	nfsi->fscache = NULL;
 	if (!S_ISREG(inode->i_mode))
 		return;
+
+	memset(&auxdata, 0, sizeof(auxdata));
+	auxdata.mtime = nfsi->vfs_inode.i_mtime;
+	auxdata.ctime = nfsi->vfs_inode.i_ctime;
+
+	if (NFS_SERVER(&nfsi->vfs_inode)->nfs_client->rpc_ops->version == 4)
+		auxdata.change_attr = inode_peek_iversion_raw(&nfsi->vfs_inode);
+
 	nfsi->fscache = fscache_acquire_cookie(NFS_SB(inode->i_sb)->fscache,
 					       &nfs_fscache_inode_object_def,
-					       nfsi, false);
+					       nfsi->fh.data, nfsi->fh.size,
+					       &auxdata, sizeof(auxdata),
+					       nfsi, nfsi->vfs_inode.i_size, false);
 }
 
 /*
@@ -195,12 +255,16 @@ void nfs_fscache_init_inode(struct inode *inode)
  */
 void nfs_fscache_clear_inode(struct inode *inode)
 {
+	struct nfs_fscache_inode_auxdata auxdata;
 	struct nfs_inode *nfsi = NFS_I(inode);
 	struct fscache_cookie *cookie = nfs_i_fscache(inode);
 
 	dfprintk(FSCACHE, "NFS: clear cookie (0x%p/0x%p)\n", nfsi, cookie);
 
-	fscache_relinquish_cookie(cookie, false);
+	memset(&auxdata, 0, sizeof(auxdata));
+	auxdata.mtime = nfsi->vfs_inode.i_mtime;
+	auxdata.ctime = nfsi->vfs_inode.i_ctime;
+	fscache_relinquish_cookie(cookie, &auxdata, false);
 	nfsi->fscache = NULL;
 }
 
@@ -232,20 +296,26 @@ static bool nfs_fscache_can_enable(void *data)
  */
 void nfs_fscache_open_file(struct inode *inode, struct file *filp)
 {
+	struct nfs_fscache_inode_auxdata auxdata;
 	struct nfs_inode *nfsi = NFS_I(inode);
 	struct fscache_cookie *cookie = nfs_i_fscache(inode);
 
 	if (!fscache_cookie_valid(cookie))
 		return;
 
+	memset(&auxdata, 0, sizeof(auxdata));
+	auxdata.mtime = nfsi->vfs_inode.i_mtime;
+	auxdata.ctime = nfsi->vfs_inode.i_ctime;
+
 	if (inode_is_open_for_write(inode)) {
 		dfprintk(FSCACHE, "NFS: nfsi 0x%p disabling cache\n", nfsi);
 		clear_bit(NFS_INO_FSCACHE, &nfsi->flags);
-		fscache_disable_cookie(cookie, true);
+		fscache_disable_cookie(cookie, &auxdata, true);
 		fscache_uncache_all_inode_pages(cookie, inode);
 	} else {
 		dfprintk(FSCACHE, "NFS: nfsi 0x%p enabling cache\n", nfsi);
-		fscache_enable_cookie(cookie, nfs_fscache_can_enable, inode);
+		fscache_enable_cookie(cookie, &auxdata, nfsi->vfs_inode.i_size,
+				      nfs_fscache_can_enable, inode);
 		if (fscache_cookie_enabled(cookie))
 			set_bit(NFS_INO_FSCACHE, &NFS_I(inode)->flags);
 	}
@@ -422,7 +492,8 @@ void __nfs_readpage_to_fscache(struct inode *inode, struct page *page, int sync)
 		 "NFS: readpage_to_fscache(fsc:%p/p:%p(i:%lx f:%lx)/%d)\n",
 		 nfs_i_fscache(inode), page, page->index, page->flags, sync);
 
-	ret = fscache_write_page(nfs_i_fscache(inode), page, GFP_KERNEL);
+	ret = fscache_write_page(nfs_i_fscache(inode), page,
+				 inode->i_size, GFP_KERNEL);
 	dfprintk(FSCACHE,
 		 "NFS:     readpage_to_fscache: p:%p(i:%lu f:%lx) ret %d\n",
 		 page, page->index, page->flags, ret);
diff --git a/fs/nfs/fscache.h b/fs/nfs/fscache.h
index d7fe3e799f2f..161ba2edb9d0 100644
--- a/fs/nfs/fscache.h
+++ b/fs/nfs/fscache.h
@@ -57,6 +57,21 @@ struct nfs_fscache_key {
 };
 
 /*
+ * Definition of the auxiliary data attached to NFS inode storage objects
+ * within the cache.
+ *
+ * The contents of this struct are recorded in the on-disk local cache in the
+ * auxiliary data attached to the data storage object backing an inode.  This
+ * permits coherency to be managed when a new inode binds to an already extant
+ * cache object.
+ */
+struct nfs_fscache_inode_auxdata {
+	struct timespec	mtime;
+	struct timespec	ctime;
+	u64		change_attr;
+};
+
+/*
  * fscache-index.c
  */
 extern struct fscache_netfs nfs_fscache_netfs;