Merge tag '5.17-rc3-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6

Pull cifs fixes from Steve French:
 "SMB3 client fixes including:

   - multiple fscache related fixes, reenabling ability to read/write to
     cached files for cifs.ko (that was temporarily disabled for cifs.ko
     a few weeks ago due to the recent fscache changes)

   - also includes a new fscache helper function ("query_occupancy")
     used by above

   - fix for multiuser mounts and NTLMSSP auth (workstation name) for
     stable

   - fix locking ordering problem in multichannel code

   - trivial malformed comment fix"

* tag '5.17-rc3-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: fix workstation_name for multiuser mounts
  Invalidate fscache cookie only when inode attributes are changed.
  cifs: Fix the readahead conversion to manage the batch when reading from cache
  cifs: Implement cache I/O by accessing the cache directly
  netfs, cachefiles: Add a method to query presence of data in the cache
  cifs: Transition from ->readpages() to ->readahead()
  cifs: unlock chan_lock before calling cifs_put_tcp_session
  Fix a warning about a malformed kernel doc comment in cifs

Documentation/filesystems/netfs_library.rst

@@ -462,6 +462,10 @@ operation table looks like the following::
 			     struct iov_iter *iter,
 			     netfs_io_terminated_t term_func,
 			     void *term_func_priv);
+
+		int (*query_occupancy)(struct netfs_cache_resources *cres,
+				       loff_t start, size_t len, size_t granularity,
+				       loff_t *_data_start, size_t *_data_len);
 	};
 
 With a termination handler function pointer::
@@ -536,6 +540,18 @@ The methods defined in the table are:
    indicating whether the termination is definitely happening in the caller's
    context.
 
+ * ``query_occupancy()``
+
+   [Required] Called to find out where the next piece of data is within a
+   particular region of the cache.  The start and length of the region to be
+   queried are passed in, along with the granularity to which the answer needs
+   to be aligned.  The function passes back the start and length of the data,
+   if any, available within that region.  Note that there may be a hole at the
+   front.
+
+   It returns 0 if some data was found, -ENODATA if there was no usable data
+   within the region or -ENOBUFS if there is no caching on this file.
+
 Note that these methods are passed a pointer to the cache resource structure,
 not the read request structure as they could be used in other situations where
 there isn't a read request structure as well, such as writing dirty data to the

fs/cachefiles/io.c

@@ -191,6 +191,64 @@ static int cachefiles_read(struct netfs_cache_resources *cres,
 	return ret;
 }
 
+/*
+ * Query the occupancy of the cache in a region, returning where the next chunk
+ * of data starts and how long it is.
+ */
+static int cachefiles_query_occupancy(struct netfs_cache_resources *cres,
+				      loff_t start, size_t len, size_t granularity,
+				      loff_t *_data_start, size_t *_data_len)
+{
+	struct cachefiles_object *object;
+	struct file *file;
+	loff_t off, off2;
+
+	*_data_start = -1;
+	*_data_len = 0;
+
+	if (!fscache_wait_for_operation(cres, FSCACHE_WANT_READ))
+		return -ENOBUFS;
+
+	object = cachefiles_cres_object(cres);
+	file = cachefiles_cres_file(cres);
+	granularity = max_t(size_t, object->volume->cache->bsize, granularity);
+
+	_enter("%pD,%li,%llx,%zx/%llx",
+	       file, file_inode(file)->i_ino, start, len,
+	       i_size_read(file_inode(file)));
+
+	off = cachefiles_inject_read_error();
+	if (off == 0)
+		off = vfs_llseek(file, start, SEEK_DATA);
+	if (off == -ENXIO)
+		return -ENODATA; /* Beyond EOF */
+	if (off < 0 && off >= (loff_t)-MAX_ERRNO)
+		return -ENOBUFS; /* Error. */
+	if (round_up(off, granularity) >= start + len)
+		return -ENODATA; /* No data in range */
+
+	off2 = cachefiles_inject_read_error();
+	if (off2 == 0)
+		off2 = vfs_llseek(file, off, SEEK_HOLE);
+	if (off2 == -ENXIO)
+		return -ENODATA; /* Beyond EOF */
+	if (off2 < 0 && off2 >= (loff_t)-MAX_ERRNO)
+		return -ENOBUFS; /* Error. */
+
+	/* Round away partial blocks */
+	off = round_up(off, granularity);
+	off2 = round_down(off2, granularity);
+	if (off2 <= off)
+		return -ENODATA;
+
+	*_data_start = off;
+	if (off2 > start + len)
+		*_data_len = len;
+	else
+		*_data_len = off2 - off;
+	return 0;
+}
+
 /*
  * Handle completion of a write to the cache.
  */
@@ -545,6 +603,7 @@ static const struct netfs_cache_ops cachefiles_netfs_cache_ops = {
 	.write			= cachefiles_write,
 	.prepare_read		= cachefiles_prepare_read,
 	.prepare_write		= cachefiles_prepare_write,
+	.query_occupancy	= cachefiles_query_occupancy,
 };
 
 /*

fs/cifs/connect.c

@@ -162,7 +162,7 @@ static void cifs_resolve_server(struct work_struct *work)
 	mutex_unlock(&server->srv_mutex);
 }
 
-/**
+/*
  * Mark all sessions and tcons for reconnect.
  *
  * @server needs to be previously set to CifsNeedReconnect.
@@ -1831,13 +1831,9 @@ void cifs_put_smb_ses(struct cifs_ses *ses)
 		int i;
 
 		for (i = 1; i < chan_count; i++) {
-			/*
-			 * note: for now, we're okay accessing ses->chans
-			 * without chan_lock. But when chans can go away, we'll
-			 * need to introduce ref counting to make sure that chan
-			 * is not freed from under us.
-			 */
+			spin_unlock(&ses->chan_lock);
 			cifs_put_tcp_session(ses->chans[i].server, 0);
+			spin_lock(&ses->chan_lock);
 			ses->chans[i].server = NULL;
 		}
 	}
@@ -1981,6 +1977,19 @@ cifs_set_cifscreds(struct smb3_fs_context *ctx, struct cifs_ses *ses)
 		}
 	}
 
+	ctx->workstation_name = kstrdup(ses->workstation_name, GFP_KERNEL);
+	if (!ctx->workstation_name) {
+		cifs_dbg(FYI, "Unable to allocate memory for workstation_name\n");
+		rc = -ENOMEM;
+		kfree(ctx->username);
+		ctx->username = NULL;
+		kfree_sensitive(ctx->password);
+		ctx->password = NULL;
+		kfree(ctx->domainname);
+		ctx->domainname = NULL;
+		goto out_key_put;
+	}
+
 out_key_put:
 	up_read(&key->sem);
 	key_put(key);

fs/cifs/fscache.c

@@ -134,37 +134,127 @@ void cifs_fscache_release_inode_cookie(struct inode *inode)
 	}
 }
 
+static inline void fscache_end_operation(struct netfs_cache_resources *cres)
+{
+	const struct netfs_cache_ops *ops = fscache_operation_valid(cres);
+
+	if (ops)
+		ops->end_operation(cres);
+}
+
 /*
- * Retrieve a page from FS-Cache
+ * Fallback page reading interface.
  */
-int __cifs_readpage_from_fscache(struct inode *inode, struct page *page)
+static int fscache_fallback_read_page(struct inode *inode, struct page *page)
 {
-	cifs_dbg(FYI, "%s: (fsc:%p, p:%p, i:0x%p\n",
-		 __func__, CIFS_I(inode)->fscache, page, inode);
-	return -ENOBUFS; // Needs conversion to using netfslib
+	struct netfs_cache_resources cres;
+	struct fscache_cookie *cookie = cifs_inode_cookie(inode);
+	struct iov_iter iter;
+	struct bio_vec bvec[1];
+	int ret;
+
+	memset(&cres, 0, sizeof(cres));
+	bvec[0].bv_page		= page;
+	bvec[0].bv_offset	= 0;
+	bvec[0].bv_len		= PAGE_SIZE;
+	iov_iter_bvec(&iter, READ, bvec, ARRAY_SIZE(bvec), PAGE_SIZE);
+
+	ret = fscache_begin_read_operation(&cres, cookie);
+	if (ret < 0)
+		return ret;
+
+	ret = fscache_read(&cres, page_offset(page), &iter, NETFS_READ_HOLE_FAIL,
+			   NULL, NULL);
+	fscache_end_operation(&cres);
+	return ret;
 }
 
 /*
- * Retrieve a set of pages from FS-Cache
+ * Fallback page writing interface.
  */
-int __cifs_readpages_from_fscache(struct inode *inode,
-				struct address_space *mapping,
-				struct list_head *pages,
-				unsigned *nr_pages)
+static int fscache_fallback_write_page(struct inode *inode, struct page *page,
+				       bool no_space_allocated_yet)
 {
-	cifs_dbg(FYI, "%s: (0x%p/%u/0x%p)\n",
-		 __func__, CIFS_I(inode)->fscache, *nr_pages, inode);
-	return -ENOBUFS; // Needs conversion to using netfslib
+	struct netfs_cache_resources cres;
+	struct fscache_cookie *cookie = cifs_inode_cookie(inode);
+	struct iov_iter iter;
+	struct bio_vec bvec[1];
+	loff_t start = page_offset(page);
+	size_t len = PAGE_SIZE;
+	int ret;
+
+	memset(&cres, 0, sizeof(cres));
+	bvec[0].bv_page		= page;
+	bvec[0].bv_offset	= 0;
+	bvec[0].bv_len		= PAGE_SIZE;
+	iov_iter_bvec(&iter, WRITE, bvec, ARRAY_SIZE(bvec), PAGE_SIZE);
+
+	ret = fscache_begin_write_operation(&cres, cookie);
+	if (ret < 0)
+		return ret;
+
+	ret = cres.ops->prepare_write(&cres, &start, &len, i_size_read(inode),
+				      no_space_allocated_yet);
+	if (ret == 0)
+		ret = fscache_write(&cres, page_offset(page), &iter, NULL, NULL);
+	fscache_end_operation(&cres);
+	return ret;
 }
 
-void __cifs_readpage_to_fscache(struct inode *inode, struct page *page)
+/*
+ * Retrieve a page from FS-Cache
+ */
+int __cifs_readpage_from_fscache(struct inode *inode, struct page *page)
 {
-	struct cifsInodeInfo *cifsi = CIFS_I(inode);
+	int ret;
 
-	WARN_ON(!cifsi->fscache);
+	cifs_dbg(FYI, "%s: (fsc:%p, p:%p, i:0x%p\n",
+		 __func__, cifs_inode_cookie(inode), page, inode);
 
+	ret = fscache_fallback_read_page(inode, page);
+	if (ret < 0)
+		return ret;
+
+	/* Read completed synchronously */
+	SetPageUptodate(page);
+	return 0;
+}
+
+void __cifs_readpage_to_fscache(struct inode *inode, struct page *page)
+{
 	cifs_dbg(FYI, "%s: (fsc: %p, p: %p, i: %p)\n",
-		 __func__, cifsi->fscache, page, inode);
+		 __func__, cifs_inode_cookie(inode), page, inode);
+
+	fscache_fallback_write_page(inode, page, true);
+}
+
+/*
+ * Query the cache occupancy.
+ */
+int __cifs_fscache_query_occupancy(struct inode *inode,
+				   pgoff_t first, unsigned int nr_pages,
+				   pgoff_t *_data_first,
+				   unsigned int *_data_nr_pages)
+{
+	struct netfs_cache_resources cres;
+	struct fscache_cookie *cookie = cifs_inode_cookie(inode);
+	loff_t start, data_start;
+	size_t len, data_len;
+	int ret;
 
-	// Needs conversion to using netfslib
+	ret = fscache_begin_read_operation(&cres, cookie);
+	if (ret < 0)
+		return ret;
+
+	start = first * PAGE_SIZE;
+	len = nr_pages * PAGE_SIZE;
+	ret = cres.ops->query_occupancy(&cres, start, len, PAGE_SIZE,
+					&data_start, &data_len);
+	if (ret == 0) {
+		*_data_first = data_start / PAGE_SIZE;
+		*_data_nr_pages = len / PAGE_SIZE;
+	}
+
+	fscache_end_operation(&cres);
+	return ret;
 }

fs/cifs/fscache.h

@@ -9,6 +9,7 @@
 #ifndef _CIFS_FSCACHE_H
 #define _CIFS_FSCACHE_H
 
+#include <linux/swap.h>
 #include <linux/fscache.h>
 
 #include "cifsglob.h"
@@ -58,14 +59,6 @@ void cifs_fscache_fill_coherency(struct inode *inode,
 }
 
 
-extern int cifs_fscache_release_page(struct page *page, gfp_t gfp);
-extern int __cifs_readpage_from_fscache(struct inode *, struct page *);
-extern int __cifs_readpages_from_fscache(struct inode *,
-					 struct address_space *,
-					 struct list_head *,
-					 unsigned *);
-extern void __cifs_readpage_to_fscache(struct inode *, struct page *);
-
 static inline struct fscache_cookie *cifs_inode_cookie(struct inode *inode)
 {
 	return CIFS_I(inode)->fscache;
@@ -80,33 +73,52 @@ static inline void cifs_invalidate_cache(struct inode *inode, unsigned int flags
 			   i_size_read(inode), flags);
 }
 
-static inline int cifs_readpage_from_fscache(struct inode *inode,
-					     struct page *page)
-{
-	if (CIFS_I(inode)->fscache)
-		return __cifs_readpage_from_fscache(inode, page);
+extern int __cifs_fscache_query_occupancy(struct inode *inode,
+					  pgoff_t first, unsigned int nr_pages,
+					  pgoff_t *_data_first,
+					  unsigned int *_data_nr_pages);
 
-	return -ENOBUFS;
+static inline int cifs_fscache_query_occupancy(struct inode *inode,
+					       pgoff_t first, unsigned int nr_pages,
+					       pgoff_t *_data_first,
+					       unsigned int *_data_nr_pages)
+{
+	if (!cifs_inode_cookie(inode))
+		return -ENOBUFS;
+	return __cifs_fscache_query_occupancy(inode, first, nr_pages,
+					      _data_first, _data_nr_pages);
 }
 
-static inline int cifs_readpages_from_fscache(struct inode *inode,
-					      struct address_space *mapping,
-					      struct list_head *pages,
-					      unsigned *nr_pages)
+extern int __cifs_readpage_from_fscache(struct inode *pinode, struct page *ppage);
+extern void __cifs_readpage_to_fscache(struct inode *pinode, struct page *ppage);
+
+
+static inline int cifs_readpage_from_fscache(struct inode *inode,
+					     struct page *page)
 {
-	if (CIFS_I(inode)->fscache)
-		return __cifs_readpages_from_fscache(inode, mapping, pages,
-						     nr_pages);
+	if (cifs_inode_cookie(inode))
+		return __cifs_readpage_from_fscache(inode, page);
 	return -ENOBUFS;
 }
 
 static inline void cifs_readpage_to_fscache(struct inode *inode,
 					    struct page *page)
 {
-	if (PageFsCache(page))
+	if (cifs_inode_cookie(inode))
 		__cifs_readpage_to_fscache(inode, page);
 }
 
+static inline int cifs_fscache_release_page(struct page *page, gfp_t gfp)
+{
+	if (PageFsCache(page)) {
+		if (current_is_kswapd() || !(gfp & __GFP_FS))
+			return false;
+		wait_on_page_fscache(page);
+		fscache_note_page_release(cifs_inode_cookie(page->mapping->host));
+	}
+	return true;
+}
+
 #else /* CONFIG_CIFS_FSCACHE */
 static inline
 void cifs_fscache_fill_coherency(struct inode *inode,
@@ -123,22 +135,29 @@ static inline void cifs_fscache_unuse_inode_cookie(struct inode *inode, bool upd
 static inline struct fscache_cookie *cifs_inode_cookie(struct inode *inode) { return NULL; }
 static inline void cifs_invalidate_cache(struct inode *inode, unsigned int flags) {}
 
-static inline int
-cifs_readpage_from_fscache(struct inode *inode, struct page *page)
+static inline int cifs_fscache_query_occupancy(struct inode *inode,
+					       pgoff_t first, unsigned int nr_pages,
+					       pgoff_t *_data_first,
+					       unsigned int *_data_nr_pages)
 {
+	*_data_first = ULONG_MAX;
+	*_data_nr_pages = 0;
 	return -ENOBUFS;
 }
 
-static inline int cifs_readpages_from_fscache(struct inode *inode,
-					      struct address_space *mapping,
-					      struct list_head *pages,
-					      unsigned *nr_pages)
+static inline int
+cifs_readpage_from_fscache(struct inode *inode, struct page *page)
 {
 	return -ENOBUFS;
 }
 
-static inline void cifs_readpage_to_fscache(struct inode *inode,
-			struct page *page) {}
+static inline
+void cifs_readpage_to_fscache(struct inode *inode, struct page *page) {}
+
+static inline int nfs_fscache_release_page(struct page *page, gfp_t gfp)
+{
+	return true; /* May release page */
+}
 
 #endif /* CONFIG_CIFS_FSCACHE */
 

fs/cifs/inode.c

@@ -83,6 +83,7 @@ static void cifs_set_ops(struct inode *inode)
 static void
 cifs_revalidate_cache(struct inode *inode, struct cifs_fattr *fattr)
 {
+	struct cifs_fscache_inode_coherency_data cd;
 	struct cifsInodeInfo *cifs_i = CIFS_I(inode);
 
 	cifs_dbg(FYI, "%s: revalidating inode %llu\n",
@@ -113,6 +114,9 @@ cifs_revalidate_cache(struct inode *inode, struct cifs_fattr *fattr)
 	cifs_dbg(FYI, "%s: invalidating inode %llu mapping\n",
 		 __func__, cifs_i->uniqueid);
 	set_bit(CIFS_INO_INVALID_MAPPING, &cifs_i->flags);
+	/* Invalidate fscache cookie */
+	cifs_fscache_fill_coherency(&cifs_i->vfs_inode, &cd);
+	fscache_invalidate(cifs_inode_cookie(inode), &cd, i_size_read(inode), 0);
 }
 
 /*
@@ -2261,8 +2265,6 @@ cifs_dentry_needs_reval(struct dentry *dentry)
 int
 cifs_invalidate_mapping(struct inode *inode)
 {
-	struct cifs_fscache_inode_coherency_data cd;
-	struct cifsInodeInfo *cifsi = CIFS_I(inode);
 	int rc = 0;
 
 	if (inode->i_mapping && inode->i_mapping->nrpages != 0) {
@@ -2272,8 +2274,6 @@ cifs_invalidate_mapping(struct inode *inode)
 				 __func__, inode);
 	}
 
-	cifs_fscache_fill_coherency(&cifsi->vfs_inode, &cd);
-	fscache_invalidate(cifs_inode_cookie(inode), &cd, i_size_read(inode), 0);
 	return rc;
 }
 

fs/cifs/sess.c

@@ -713,7 +713,11 @@ static int size_of_ntlmssp_blob(struct cifs_ses *ses, int base_size)
 	else
 		sz += sizeof(__le16);
 
-	sz += sizeof(__le16) * strnlen(ses->workstation_name, CIFS_MAX_WORKSTATION_LEN);
+	if (ses->workstation_name)
+		sz += sizeof(__le16) * strnlen(ses->workstation_name,
+			CIFS_MAX_WORKSTATION_LEN);
+	else
+		sz += sizeof(__le16);
 
 	return sz;
 }

include/linux/netfs.h

@@ -244,6 +244,13 @@ struct netfs_cache_ops {
 	int (*prepare_write)(struct netfs_cache_resources *cres,
 			     loff_t *_start, size_t *_len, loff_t i_size,
 			     bool no_space_allocated_yet);
+
+	/* Query the occupancy of the cache in a region, returning where the
+	 * next chunk of data starts and how long it is.
+	 */
+	int (*query_occupancy)(struct netfs_cache_resources *cres,
+			       loff_t start, size_t len, size_t granularity,
+			       loff_t *_data_start, size_t *_data_len);
 };
 
 struct readahead_control;