*
*/
-#include <linux/config.h>
#include <linux/slab.h>
#include <linux/file.h>
#include <linux/sunrpc/clnt.h>
#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;
}
* 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)
{
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;
}
}
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));
/* 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;
}
/**
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;
}
/**
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;
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
* 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)
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),
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);
}
git://git.onelab.eu / linux-2.6.git / blobdiff