X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=fs%2Fnfs%2Fpagelist.c;h=ca4b1d4ff42b0f7d337ad01fa7c1675f959c4134;hb=refs%2Fheads%2Fvserver;hp=c82fc852840ead607eb1ac6d2ee404bd1bfbbaf4;hpb=5273a3df6485dc2ad6aa7ddd441b9a21970f003b;p=linux-2.6.git

diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c
index c82fc8528..ca4b1d4ff 100644
--- a/fs/nfs/pagelist.c
+++ b/fs/nfs/pagelist.c
@@ -9,7 +9,6 @@
  *
  */
 
-#include <linux/config.h>
 #include <linux/slab.h>
 #include <linux/file.h>
 #include <linux/sunrpc/clnt.h>
@@ -18,25 +17,20 @@
 #include <linux/nfs_page.h>
 #include <linux/nfs_fs.h>
 #include <linux/nfs_mount.h>
+#include <linux/writeback.h>
 
 #define NFS_PARANOIA 1
 
-/*
- * Spinlock
- */
-spinlock_t nfs_wreq_lock = SPIN_LOCK_UNLOCKED;
-
-static kmem_cache_t *nfs_page_cachep;
+static struct kmem_cache *nfs_page_cachep;
 
 static inline struct nfs_page *
 nfs_page_alloc(void)
 {
 	struct nfs_page	*p;
-	p = kmem_cache_alloc(nfs_page_cachep, SLAB_KERNEL);
+	p = kmem_cache_alloc(nfs_page_cachep, GFP_KERNEL);
 	if (p) {
 		memset(p, 0, sizeof(*p));
 		INIT_LIST_HEAD(&p->wb_list);
-		init_waitqueue_head(&p->wb_wait);
 	}
 	return p;
 }
@@ -62,7 +56,7 @@ nfs_page_free(struct nfs_page *p)
  * User should ensure it is safe to sleep in this function.
  */
 struct nfs_page *
-nfs_create_request(struct file *file, struct inode *inode,
+nfs_create_request(struct nfs_open_context *ctx, struct inode *inode,
 		   struct page *page,
 		   unsigned int offset, unsigned int count)
 {
@@ -91,38 +85,76 @@ nfs_create_request(struct file *file, struct inode *inode,
 	atomic_set(&req->wb_complete, 0);
 	req->wb_index	= page->index;
 	page_cache_get(page);
+	BUG_ON(PagePrivate(page));
+	BUG_ON(!PageLocked(page));
+	BUG_ON(page->mapping->host != inode);
 	req->wb_offset  = offset;
 	req->wb_pgbase	= offset;
 	req->wb_bytes   = count;
-	req->wb_inode   = inode;
-	req->wb_count   = 1;
-	server->rpc_ops->request_init(req, file);
+	atomic_set(&req->wb_count, 1);
+	req->wb_context = get_nfs_open_context(ctx);
 
 	return req;
 }
 
+/**
+ * nfs_unlock_request - Unlock request and wake up sleepers.
+ * @req:
+ */
+void nfs_unlock_request(struct nfs_page *req)
+{
+	if (!NFS_WBACK_BUSY(req)) {
+		printk(KERN_ERR "NFS: Invalid unlock attempted\n");
+		BUG();
+	}
+	smp_mb__before_clear_bit();
+	clear_bit(PG_BUSY, &req->wb_flags);
+	smp_mb__after_clear_bit();
+	wake_up_bit(&req->wb_flags, PG_BUSY);
+	nfs_release_request(req);
+}
+
+/**
+ * nfs_set_page_writeback_locked - Lock a request for writeback
+ * @req:
+ */
+int nfs_set_page_writeback_locked(struct nfs_page *req)
+{
+	struct nfs_inode *nfsi = NFS_I(req->wb_context->dentry->d_inode);
+
+	if (!nfs_lock_request(req))
+		return 0;
+	radix_tree_tag_set(&nfsi->nfs_page_tree, req->wb_index, NFS_PAGE_TAG_WRITEBACK);
+	return 1;
+}
+
+/**
+ * nfs_clear_page_writeback - Unlock request and wake up sleepers
+ */
+void nfs_clear_page_writeback(struct nfs_page *req)
+{
+	struct nfs_inode *nfsi = NFS_I(req->wb_context->dentry->d_inode);
+
+	if (req->wb_page != NULL) {
+		spin_lock(&nfsi->req_lock);
+		radix_tree_tag_clear(&nfsi->nfs_page_tree, req->wb_index, NFS_PAGE_TAG_WRITEBACK);
+		spin_unlock(&nfsi->req_lock);
+	}
+	nfs_unlock_request(req);
+}
+
 /**
  * nfs_clear_request - Free up all resources allocated to the request
  * @req:
  *
- * Release all resources associated with a write request after it
+ * Release page resources associated with a write request after it
  * has completed.
  */
 void nfs_clear_request(struct nfs_page *req)
 {
-	if (req->wb_state)
-		req->wb_state = NULL;
-	/* Release struct file or cached credential */
-	if (req->wb_file) {
-		fput(req->wb_file);
-		req->wb_file = NULL;
-	}
-	if (req->wb_cred) {
-		put_rpccred(req->wb_cred);
-		req->wb_cred = NULL;
-	}
-	if (req->wb_page) {
-		page_cache_release(req->wb_page);
+	struct page *page = req->wb_page;
+	if (page != NULL) {
+		page_cache_release(page);
 		req->wb_page = NULL;
 	}
 }
@@ -137,12 +169,8 @@ void nfs_clear_request(struct nfs_page *req)
 void
 nfs_release_request(struct nfs_page *req)
 {
-	spin_lock(&nfs_wreq_lock);
-	if (--req->wb_count) {
-		spin_unlock(&nfs_wreq_lock);
+	if (!atomic_dec_and_test(&req->wb_count))
 		return;
-	}
-	spin_unlock(&nfs_wreq_lock);
 
 #ifdef NFS_PARANOIA
 	BUG_ON (!list_empty(&req->wb_list));
@@ -151,37 +179,19 @@ nfs_release_request(struct nfs_page *req)
 
 	/* Release struct file or cached credential */
 	nfs_clear_request(req);
+	put_nfs_open_context(req->wb_context);
 	nfs_page_free(req);
 }
 
-/**
- * nfs_list_add_request - Insert a request into a sorted list
- * @req: request
- * @head: head of list into which to insert the request.
- *
- * Note that the wb_list is sorted by page index in order to facilitate
- * coalescing of requests.
- * We use an insertion sort that is optimized for the case of appended
- * writes.
- */
-void
-nfs_list_add_request(struct nfs_page *req, struct list_head *head)
+static int nfs_wait_bit_interruptible(void *word)
 {
-	struct list_head *pos;
+	int ret = 0;
 
-#ifdef NFS_PARANOIA
-	if (!list_empty(&req->wb_list)) {
-		printk(KERN_ERR "NFS: Add to list failed!\n");
-		BUG();
-	}
-#endif
-	list_for_each_prev(pos, head) {
-		struct nfs_page	*p = nfs_list_entry(pos);
-		if (p->wb_index < req->wb_index)
-			break;
-	}
-	list_add(&req->wb_list, pos);
-	req->wb_list_head = head;
+	if (signal_pending(current))
+		ret = -ERESTARTSYS;
+	else
+		schedule();
+	return ret;
 }
 
 /**
@@ -194,12 +204,22 @@ nfs_list_add_request(struct nfs_page *req, struct list_head *head)
 int
 nfs_wait_on_request(struct nfs_page *req)
 {
-	struct inode	*inode = req->wb_inode;
-        struct rpc_clnt	*clnt = NFS_CLIENT(inode);
-
-	if (!NFS_WBACK_BUSY(req))
-		return 0;
-	return nfs_wait_event(clnt, req->wb_wait, !NFS_WBACK_BUSY(req));
+        struct rpc_clnt	*clnt = NFS_CLIENT(req->wb_context->dentry->d_inode);
+	sigset_t oldmask;
+	int ret = 0;
+
+	if (!test_bit(PG_BUSY, &req->wb_flags))
+		goto out;
+	/*
+	 * Note: the call to rpc_clnt_sigmask() suffices to ensure that we
+	 *	 are not interrupted if intr flag is not set
+	 */
+	rpc_clnt_sigmask(clnt, &oldmask);
+	ret = out_of_line_wait_on_bit(&req->wb_flags, PG_BUSY,
+			nfs_wait_bit_interruptible, TASK_INTERRUPTIBLE);
+	rpc_clnt_sigunmask(clnt, &oldmask);
+out:
+	return ret;
 }
 
 /**
@@ -224,7 +244,11 @@ nfs_coalesce_requests(struct list_head *head, struct list_head *dst,
 
 		req = nfs_list_entry(head->next);
 		if (prev) {
-			if (req->wb_cred != prev->wb_cred)
+			if (req->wb_context->cred != prev->wb_context->cred)
+				break;
+			if (req->wb_context->lockowner != prev->wb_context->lockowner)
+				break;
+			if (req->wb_context->state != prev->wb_context->state)
 				break;
 			if (req->wb_index != (prev->wb_index + 1))
 				break;
@@ -243,8 +267,82 @@ nfs_coalesce_requests(struct list_head *head, struct list_head *dst,
 	return npages;
 }
 
+#define NFS_SCAN_MAXENTRIES 16
+/**
+ * nfs_scan_dirty - Scan the radix tree for dirty requests
+ * @mapping: pointer to address space
+ * @wbc: writeback_control structure
+ * @dst: Destination list
+ *
+ * Moves elements from one of the inode request lists.
+ * If the number of requests is set to 0, the entire address_space
+ * starting at index idx_start, is scanned.
+ * The requests are *not* checked to ensure that they form a contiguous set.
+ * You must be holding the inode's req_lock when calling this function
+ */
+long nfs_scan_dirty(struct address_space *mapping,
+			struct writeback_control *wbc,
+			struct list_head *dst)
+{
+	struct nfs_inode *nfsi = NFS_I(mapping->host);
+	struct nfs_page *pgvec[NFS_SCAN_MAXENTRIES];
+	struct nfs_page *req;
+	pgoff_t idx_start, idx_end;
+	long res = 0;
+	int found, i;
+
+	if (nfsi->ndirty == 0)
+		return 0;
+	if (wbc->range_cyclic) {
+		idx_start = 0;
+		idx_end = ULONG_MAX;
+	} else if (wbc->range_end == 0) {
+		idx_start = wbc->range_start >> PAGE_CACHE_SHIFT;
+		idx_end = ULONG_MAX;
+	} else {
+		idx_start = wbc->range_start >> PAGE_CACHE_SHIFT;
+		idx_end = wbc->range_end >> PAGE_CACHE_SHIFT;
+	}
+
+	for (;;) {
+		unsigned int toscan = NFS_SCAN_MAXENTRIES;
+
+		found = radix_tree_gang_lookup_tag(&nfsi->nfs_page_tree,
+				(void **)&pgvec[0], idx_start, toscan,
+				NFS_PAGE_TAG_DIRTY);
+
+		/* Did we make progress? */
+		if (found <= 0)
+			break;
+
+		for (i = 0; i < found; i++) {
+			req = pgvec[i];
+			if (!wbc->range_cyclic && req->wb_index > idx_end)
+				goto out;
+
+			/* Try to lock request and mark it for writeback */
+			if (!nfs_set_page_writeback_locked(req))
+				goto next;
+			radix_tree_tag_clear(&nfsi->nfs_page_tree,
+					req->wb_index, NFS_PAGE_TAG_DIRTY);
+			nfsi->ndirty--;
+			nfs_list_remove_request(req);
+			nfs_list_add_request(req, dst);
+			res++;
+			if (res == LONG_MAX)
+				goto out;
+next:
+			idx_start = req->wb_index + 1;
+		}
+	}
+out:
+	WARN_ON ((nfsi->ndirty == 0) != list_empty(&nfsi->dirty));
+	return res;
+}
+
 /**
  * nfs_scan_list - Scan a list for matching requests
+ * @nfsi: NFS inode
  * @head: One of the NFS inode request lists
  * @dst: Destination list
  * @idx_start: lower bound of page->index to scan
@@ -254,16 +352,17 @@ nfs_coalesce_requests(struct list_head *head, struct list_head *dst,
  * If the number of requests is set to 0, the entire address_space
  * starting at index idx_start, is scanned.
  * The requests are *not* checked to ensure that they form a contiguous set.
- * You must be holding the nfs_wreq_lock when calling this function
+ * You must be holding the inode's req_lock when calling this function
  */
-int
-nfs_scan_list(struct list_head *head, struct list_head *dst,
-	      unsigned long idx_start, unsigned int npages)
+int nfs_scan_list(struct nfs_inode *nfsi, struct list_head *head,
+		struct list_head *dst, unsigned long idx_start,
+		unsigned int npages)
 {
-	struct list_head	*pos, *tmp;
-	struct nfs_page		*req;
-	unsigned long		idx_end;
-	int			res;
+	struct nfs_page *pgvec[NFS_SCAN_MAXENTRIES];
+	struct nfs_page *req;
+	unsigned long idx_end;
+	int found, i;
+	int res;
 
 	res = 0;
 	if (npages == 0)
@@ -271,25 +370,32 @@ nfs_scan_list(struct list_head *head, struct list_head *dst,
 	else
 		idx_end = idx_start + npages - 1;
 
-	list_for_each_safe(pos, tmp, head) {
-
-		req = nfs_list_entry(pos);
-
-		if (req->wb_index < idx_start)
-			continue;
-		if (req->wb_index > idx_end)
+	for (;;) {
+		found = radix_tree_gang_lookup(&nfsi->nfs_page_tree,
+				(void **)&pgvec[0], idx_start,
+				NFS_SCAN_MAXENTRIES);
+		if (found <= 0)
 			break;
+		for (i = 0; i < found; i++) {
+			req = pgvec[i];
+			if (req->wb_index > idx_end)
+				goto out;
+			idx_start = req->wb_index + 1;
+			if (req->wb_list_head != head)
+				continue;
+			if (nfs_set_page_writeback_locked(req)) {
+				nfs_list_remove_request(req);
+				nfs_list_add_request(req, dst);
+				res++;
+			}
+		}
 
-		if (!nfs_lock_request(req))
-			continue;
-		nfs_list_remove_request(req);
-		nfs_list_add_request(req, dst);
-		res++;
 	}
+out:
 	return res;
 }
 
-int nfs_init_nfspagecache(void)
+int __init nfs_init_nfspagecache(void)
 {
 	nfs_page_cachep = kmem_cache_create("nfs_page",
 					    sizeof(struct nfs_page),
@@ -303,7 +409,6 @@ int nfs_init_nfspagecache(void)
 
 void nfs_destroy_nfspagecache(void)
 {
-	if (kmem_cache_destroy(nfs_page_cachep))
-		printk(KERN_INFO "nfs_page: not all structures were freed\n");
+	kmem_cache_destroy(nfs_page_cachep);
 }