return result;
}
-static ssize_t nfs_direct_write_seg(struct inode *inode, struct nfs_open_context *ctx, unsigned long user_addr, size_t count, loff_t file_offset, struct page **pages, int nr_pages)
+static struct nfs_direct_req *nfs_direct_write_alloc(size_t nbytes, size_t wsize)
{
- const unsigned int wsize = NFS_SERVER(inode)->wsize;
- size_t request;
- int curpage, need_commit;
- ssize_t result, tot_bytes;
- struct nfs_writeverf first_verf;
- struct nfs_write_data *wdata;
-
- wdata = nfs_writedata_alloc(NFS_SERVER(inode)->wpages);
- if (!wdata)
- return -ENOMEM;
+ struct list_head *list;
+ struct nfs_direct_req *dreq;
+ unsigned int writes = 0;
+ unsigned int wpages = (wsize + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
- wdata->inode = inode;
- wdata->cred = ctx->cred;
- wdata->args.fh = NFS_FH(inode);
- wdata->args.context = ctx;
- wdata->args.stable = NFS_UNSTABLE;
- if (IS_SYNC(inode) || NFS_PROTO(inode)->version == 2 || count <= wsize)
- wdata->args.stable = NFS_FILE_SYNC;
- wdata->res.fattr = &wdata->fattr;
- wdata->res.verf = &wdata->verf;
+ dreq = nfs_direct_req_alloc();
+ if (!dreq)
+ return NULL;
+
+ list = &dreq->list;
+ for(;;) {
+ struct nfs_write_data *data = nfs_writedata_alloc(wpages);
+
+ if (unlikely(!data)) {
+ while (!list_empty(list)) {
+ data = list_entry(list->next,
+ struct nfs_write_data, pages);
+ list_del(&data->pages);
+ nfs_writedata_free(data);
+ }
+ kref_put(&dreq->kref, nfs_direct_req_release);
+ return NULL;
+ }
+
+ INIT_LIST_HEAD(&data->pages);
+ list_add(&data->pages, list);
+
+ data->req = (struct nfs_page *) dreq;
+ writes++;
+ if (nbytes <= wsize)
+ break;
+ nbytes -= wsize;
+ }
+ kref_get(&dreq->kref);
+ atomic_set(&dreq->complete, writes);
+ return dreq;
+}
+
+/*
+ * Collects and returns the final error value/byte-count.
+ */
+static ssize_t nfs_direct_write_wait(struct nfs_direct_req *dreq, int intr)
+{
+ int result = 0;
+
+ if (intr) {
+ result = wait_event_interruptible(dreq->wait,
+ (atomic_read(&dreq->complete) == 0));
+ } else {
+ wait_event(dreq->wait, (atomic_read(&dreq->complete) == 0));
+ }
+
+ if (!result)
+ result = atomic_read(&dreq->error);
+ if (!result)
+ result = atomic_read(&dreq->count);
+
+ kref_put(&dreq->kref, nfs_direct_req_release);
+ return (ssize_t) result;
+}
+
+static void nfs_direct_write_result(struct rpc_task *task, void *calldata)
+{
+ struct nfs_write_data *data = calldata;
+ struct nfs_direct_req *dreq = (struct nfs_direct_req *) data->req;
+ int status = task->tk_status;
+
+ if (nfs_writeback_done(task, data) != 0)
+ return;
+ /* If the server fell back to an UNSTABLE write, it's an error. */
+ if (unlikely(data->res.verf->committed != NFS_FILE_SYNC))
+ status = -EIO;
+
+ if (likely(status >= 0))
+ atomic_add(data->res.count, &dreq->count);
+ else
+ atomic_set(&dreq->error, status);
+
+ if (unlikely(atomic_dec_and_test(&dreq->complete)))
+ nfs_direct_complete(dreq);
+}
+
+static const struct rpc_call_ops nfs_write_direct_ops = {
+ .rpc_call_done = nfs_direct_write_result,
+ .rpc_release = nfs_writedata_release,
+};
+
+/*
+ * For each nfs_write_data struct that was allocated on the list, dispatch
+ * an NFS WRITE operation
+ *
+ * XXX: For now, support only FILE_SYNC writes. Later we may add
+ * support for UNSTABLE + COMMIT.
+ */
+static void nfs_direct_write_schedule(struct nfs_direct_req *dreq, struct inode *inode, struct nfs_open_context *ctx, unsigned long user_addr, size_t count, loff_t file_offset)
+{
+ struct list_head *list = &dreq->list;
+ struct page **pages = dreq->pages;
+ size_t wsize = NFS_SERVER(inode)->wsize;
+ unsigned int curpage, pgbase;
- nfs_begin_data_update(inode);
-retry:
- need_commit = 0;
- tot_bytes = 0;
curpage = 0;
- request = count;
- wdata->args.pgbase = user_addr & ~PAGE_MASK;
- wdata->args.offset = file_offset;
+ pgbase = user_addr & ~PAGE_MASK;
do {
- wdata->args.count = request;
- if (wdata->args.count > wsize)
- wdata->args.count = wsize;
- wdata->args.pages = &pages[curpage];
+ struct nfs_write_data *data;
+ size_t bytes;
+
+ bytes = wsize;
+ if (count < wsize)
+ bytes = count;
+
+ data = list_entry(list->next, struct nfs_write_data, pages);
+ list_del_init(&data->pages);
+
+ data->inode = inode;
+ data->cred = ctx->cred;
+ data->args.fh = NFS_FH(inode);
+ data->args.context = ctx;
+ data->args.offset = file_offset;
+ data->args.pgbase = pgbase;
+ data->args.pages = &pages[curpage];
+ data->args.count = bytes;
+ data->res.fattr = &data->fattr;
+ data->res.count = bytes;
+
+ rpc_init_task(&data->task, NFS_CLIENT(inode), RPC_TASK_ASYNC,
+ &nfs_write_direct_ops, data);
+ NFS_PROTO(inode)->write_setup(data, FLUSH_STABLE);
- dprintk("NFS: direct write: c=%u o=%Ld ua=%lu, pb=%u, cp=%u\n",
- wdata->args.count, (long long) wdata->args.offset,
- user_addr + tot_bytes, wdata->args.pgbase, curpage);
+ data->task.tk_priority = RPC_PRIORITY_NORMAL;
+ data->task.tk_cookie = (unsigned long) inode;
lock_kernel();
- result = NFS_PROTO(inode)->write(wdata);
+ rpc_execute(&data->task);
unlock_kernel();
- if (result <= 0) {
- if (tot_bytes > 0)
- break;
- goto out;
- }
+ dfprintk(VFS, "NFS: %4d initiated direct write call (req %s/%Ld, %u bytes @ offset %Lu)\n",
+ data->task.tk_pid,
+ inode->i_sb->s_id,
+ (long long)NFS_FILEID(inode),
+ bytes,
+ (unsigned long long)data->args.offset);
- if (tot_bytes == 0)
- memcpy(&first_verf.verifier, &wdata->verf.verifier,
- sizeof(first_verf.verifier));
- if (wdata->verf.committed != NFS_FILE_SYNC) {
- need_commit = 1;
- if (memcmp(&first_verf.verifier, &wdata->verf.verifier,
- sizeof(first_verf.verifier)))
- goto sync_retry;
- }
+ file_offset += bytes;
+ pgbase += bytes;
+ curpage += pgbase >> PAGE_SHIFT;
+ pgbase &= ~PAGE_MASK;
- tot_bytes += result;
+ count -= bytes;
+ } while (count != 0);
+}
- /* in case of a short write: stop now, let the app recover */
- if (result < wdata->args.count)
- break;
+static ssize_t nfs_direct_write_seg(struct inode *inode, struct nfs_open_context *ctx, unsigned long user_addr, size_t count, loff_t file_offset, struct page **pages, int nr_pages)
+{
+ ssize_t result;
+ sigset_t oldset;
+ struct rpc_clnt *clnt = NFS_CLIENT(inode);
+ struct nfs_direct_req *dreq;
- wdata->args.offset += result;
- wdata->args.pgbase += result;
- curpage += wdata->args.pgbase >> PAGE_SHIFT;
- wdata->args.pgbase &= ~PAGE_MASK;
- request -= result;
- } while (request != 0);
+ dreq = nfs_direct_write_alloc(count, NFS_SERVER(inode)->wsize);
+ if (!dreq)
+ return -ENOMEM;
- /*
- * Commit data written so far, even in the event of an error
- */
- if (need_commit) {
- wdata->args.count = tot_bytes;
- wdata->args.offset = file_offset;
+ dreq->pages = pages;
+ dreq->npages = nr_pages;
- lock_kernel();
- result = NFS_PROTO(inode)->commit(wdata);
- unlock_kernel();
+ nfs_begin_data_update(inode);
- if (result < 0 || memcmp(&first_verf.verifier,
- &wdata->verf.verifier,
- sizeof(first_verf.verifier)) != 0)
- goto sync_retry;
- }
- result = tot_bytes;
+ rpc_clnt_sigmask(clnt, &oldset);
+ nfs_direct_write_schedule(dreq, inode, ctx, user_addr, count,
+ file_offset);
+ result = nfs_direct_write_wait(dreq, clnt->cl_intr);
+ rpc_clnt_sigunmask(clnt, &oldset);
-out:
nfs_end_data_update(inode);
- nfs_writedata_free(wdata);
- return result;
-sync_retry:
- wdata->args.stable = NFS_FILE_SYNC;
- goto retry;
+ return result;
}
/*
nfs_add_stats(inode, NFSIOS_DIRECTWRITTENBYTES, size);
result = nfs_direct_write_seg(inode, ctx, user_addr, size,
file_offset, pages, page_count);
- nfs_free_user_pages(pages, page_count, 0);
if (result <= 0) {
if (tot_bytes > 0)
projects / linux-beck.git / commitdiff