#include <linux/slab.h>
#include <linux/file.h>
+#include <linux/sched.h>
#include <linux/sunrpc/clnt.h>
#include <linux/nfs3.h>
#include <linux/nfs4.h>
req->wb_offset = offset;
req->wb_pgbase = offset;
req->wb_bytes = count;
- atomic_set(&req->wb_count, 1);
req->wb_context = get_nfs_open_context(ctx);
-
+ kref_init(&req->wb_kref);
return req;
}
}
/**
- * nfs_set_page_writeback_locked - Lock a request for writeback
+ * nfs_set_page_tag_locked - Tag a request as locked
* @req:
*/
-int nfs_set_page_writeback_locked(struct nfs_page *req)
+static int nfs_set_page_tag_locked(struct nfs_page *req)
{
- struct nfs_inode *nfsi = NFS_I(req->wb_context->dentry->d_inode);
+ struct nfs_inode *nfsi = NFS_I(req->wb_context->path.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);
+ radix_tree_tag_set(&nfsi->nfs_page_tree, req->wb_index, NFS_PAGE_TAG_LOCKED);
return 1;
}
/**
- * nfs_clear_page_writeback - Unlock request and wake up sleepers
+ * nfs_clear_page_tag_locked - Clear request tag and wake up sleepers
*/
-void nfs_clear_page_writeback(struct nfs_page *req)
+void nfs_clear_page_tag_locked(struct nfs_page *req)
{
- struct nfs_inode *nfsi = NFS_I(req->wb_context->dentry->d_inode);
+ struct inode *inode = req->wb_context->path.dentry->d_inode;
+ struct nfs_inode *nfsi = NFS_I(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);
+ spin_lock(&inode->i_lock);
+ radix_tree_tag_clear(&nfsi->nfs_page_tree, req->wb_index, NFS_PAGE_TAG_LOCKED);
+ spin_unlock(&inode->i_lock);
}
nfs_unlock_request(req);
}
*
* Note: Should never be called with the spinlock held!
*/
-void
-nfs_release_request(struct nfs_page *req)
+static void nfs_free_request(struct kref *kref)
{
- if (!atomic_dec_and_test(&req->wb_count))
- return;
+ struct nfs_page *req = container_of(kref, struct nfs_page, wb_kref);
/* Release struct file or cached credential */
nfs_clear_request(req);
nfs_page_free(req);
}
+void nfs_release_request(struct nfs_page *req)
+{
+ kref_put(&req->wb_kref, nfs_free_request);
+}
+
static int nfs_wait_bit_interruptible(void *word)
{
int ret = 0;
int
nfs_wait_on_request(struct nfs_page *req)
{
- struct rpc_clnt *clnt = NFS_CLIENT(req->wb_context->dentry->d_inode);
+ struct rpc_clnt *clnt = NFS_CLIENT(req->wb_context->path.dentry->d_inode);
sigset_t oldmask;
int ret = 0;
nfs_pageio_doio(desc);
}
+/**
+ * nfs_pageio_cond_complete - Conditional I/O completion
+ * @desc: pointer to io descriptor
+ * @index: page index
+ *
+ * It is important to ensure that processes don't try to take locks
+ * on non-contiguous ranges of pages as that might deadlock. This
+ * function should be called before attempting to wait on a locked
+ * nfs_page. It will complete the I/O if the page index 'index'
+ * is not contiguous with the existing list of pages in 'desc'.
+ */
+void nfs_pageio_cond_complete(struct nfs_pageio_descriptor *desc, pgoff_t index)
+{
+ if (!list_empty(&desc->pg_list)) {
+ struct nfs_page *prev = nfs_list_entry(desc->pg_list.prev);
+ if (index != prev->wb_index + 1)
+ nfs_pageio_doio(desc);
+ }
+}
+
#define NFS_SCAN_MAXENTRIES 16
/**
* 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
* @npages: idx_start + npages sets the upper bound to scan.
+ * @tag: tag to scan for
*
* 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
+ * You must be holding the inode's i_lock when calling this function
*/
-int nfs_scan_list(struct nfs_inode *nfsi, struct list_head *head,
+int nfs_scan_list(struct nfs_inode *nfsi,
struct list_head *dst, pgoff_t idx_start,
- unsigned int npages)
+ unsigned int npages, int tag)
{
struct nfs_page *pgvec[NFS_SCAN_MAXENTRIES];
struct nfs_page *req;
idx_end = idx_start + npages - 1;
for (;;) {
- found = radix_tree_gang_lookup(&nfsi->nfs_page_tree,
+ found = radix_tree_gang_lookup_tag(&nfsi->nfs_page_tree,
(void **)&pgvec[0], idx_start,
- NFS_SCAN_MAXENTRIES);
+ NFS_SCAN_MAXENTRIES, tag);
if (found <= 0)
break;
for (i = 0; i < found; 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)) {
+ if (nfs_set_page_tag_locked(req)) {
nfs_list_remove_request(req);
+ radix_tree_tag_clear(&nfsi->nfs_page_tree,
+ req->wb_index, tag);
nfs_list_add_request(req, dst);
res++;
+ if (res == INT_MAX)
+ goto out;
}
}
-
+ /* for latency reduction */
+ cond_resched_lock(&nfsi->vfs_inode.i_lock);
}
out:
return res;
nfs_page_cachep = kmem_cache_create("nfs_page",
sizeof(struct nfs_page),
0, SLAB_HWCACHE_ALIGN,
- NULL, NULL);
+ NULL);
if (nfs_page_cachep == NULL)
return -ENOMEM;
git://bbs.cooldavid.org / net-next-2.6.git / blobdiff