diff options
Diffstat (limited to 'fs/nfs/read.c')
-rw-r--r-- | fs/nfs/read.c | 179 |
1 files changed, 84 insertions, 95 deletions
diff --git a/fs/nfs/read.c b/fs/nfs/read.c index 244a8c45b68..a9c26521a9e 100644 --- a/fs/nfs/read.c +++ b/fs/nfs/read.c @@ -30,6 +30,7 @@ #include <asm/system.h> +#include "internal.h" #include "iostat.h" #define NFSDBG_FACILITY NFSDBG_PAGECACHE @@ -65,32 +66,22 @@ struct nfs_read_data *nfs_readdata_alloc(size_t len) return p; } -static void nfs_readdata_free(struct nfs_read_data *p) +static void nfs_readdata_rcu_free(struct rcu_head *head) { + struct nfs_read_data *p = container_of(head, struct nfs_read_data, task.u.tk_rcu); if (p && (p->pagevec != &p->page_array[0])) kfree(p->pagevec); mempool_free(p, nfs_rdata_mempool); } -void nfs_readdata_release(void *data) +static void nfs_readdata_free(struct nfs_read_data *rdata) { - nfs_readdata_free(data); + call_rcu_bh(&rdata->task.u.tk_rcu, nfs_readdata_rcu_free); } -static -unsigned int nfs_page_length(struct inode *inode, struct page *page) +void nfs_readdata_release(void *data) { - loff_t i_size = i_size_read(inode); - unsigned long idx; - - if (i_size <= 0) - return 0; - idx = (i_size - 1) >> PAGE_CACHE_SHIFT; - if (page->index > idx) - return 0; - if (page->index != idx) - return PAGE_CACHE_SIZE; - return 1 + ((i_size - 1) & (PAGE_CACHE_SIZE - 1)); + nfs_readdata_free(data); } static @@ -139,12 +130,12 @@ static int nfs_readpage_sync(struct nfs_open_context *ctx, struct inode *inode, { unsigned int rsize = NFS_SERVER(inode)->rsize; unsigned int count = PAGE_CACHE_SIZE; - int result; + int result = -ENOMEM; struct nfs_read_data *rdata; rdata = nfs_readdata_alloc(count); if (!rdata) - return -ENOMEM; + goto out_unlock; memset(rdata, 0, sizeof(*rdata)); rdata->flags = (IS_SWAPFILE(inode)? NFS_RPC_SWAPFLAGS : 0); @@ -212,8 +203,9 @@ static int nfs_readpage_sync(struct nfs_open_context *ctx, struct inode *inode, result = 0; io_error: - unlock_page(page); nfs_readdata_free(rdata); +out_unlock: + unlock_page(page); return result; } @@ -224,7 +216,7 @@ static int nfs_readpage_async(struct nfs_open_context *ctx, struct inode *inode, struct nfs_page *new; unsigned int len; - len = nfs_page_length(inode, page); + len = nfs_page_length(page); if (len == 0) return nfs_return_empty_page(page); new = nfs_create_request(ctx, inode, page, 0, len); @@ -316,9 +308,7 @@ static void nfs_execute_read(struct nfs_read_data *data) sigset_t oldset; rpc_clnt_sigmask(clnt, &oldset); - lock_kernel(); rpc_execute(&data->task); - unlock_kernel(); rpc_clnt_sigunmask(clnt, &oldset); } @@ -455,6 +445,55 @@ nfs_pagein_list(struct list_head *head, int rpages) } /* + * This is the callback from RPC telling us whether a reply was + * received or some error occurred (timeout or socket shutdown). + */ +int nfs_readpage_result(struct rpc_task *task, struct nfs_read_data *data) +{ + int status; + + dprintk("%s: %4d, (status %d)\n", __FUNCTION__, task->tk_pid, + task->tk_status); + + status = NFS_PROTO(data->inode)->read_done(task, data); + if (status != 0) + return status; + + nfs_add_stats(data->inode, NFSIOS_SERVERREADBYTES, data->res.count); + + if (task->tk_status == -ESTALE) { + set_bit(NFS_INO_STALE, &NFS_FLAGS(data->inode)); + nfs_mark_for_revalidate(data->inode); + } + spin_lock(&data->inode->i_lock); + NFS_I(data->inode)->cache_validity |= NFS_INO_INVALID_ATIME; + spin_unlock(&data->inode->i_lock); + return 0; +} + +static int nfs_readpage_retry(struct rpc_task *task, struct nfs_read_data *data) +{ + struct nfs_readargs *argp = &data->args; + struct nfs_readres *resp = &data->res; + + if (resp->eof || resp->count == argp->count) + return 0; + + /* This is a short read! */ + nfs_inc_stats(data->inode, NFSIOS_SHORTREAD); + /* Has the server at least made some progress? */ + if (resp->count == 0) + return 0; + + /* Yes, so retry the read at the end of the data */ + argp->offset += resp->count; + argp->pgbase += resp->count; + argp->count -= resp->count; + rpc_restart_call(task); + return -EAGAIN; +} + +/* * Handle a read reply that fills part of a page. */ static void nfs_readpage_result_partial(struct rpc_task *task, void *calldata) @@ -463,12 +502,16 @@ static void nfs_readpage_result_partial(struct rpc_task *task, void *calldata) struct nfs_page *req = data->req; struct page *page = req->wb_page; - if (likely(task->tk_status >= 0)) - nfs_readpage_truncate_uninitialised_page(data); - else - SetPageError(page); if (nfs_readpage_result(task, data) != 0) return; + + if (likely(task->tk_status >= 0)) { + nfs_readpage_truncate_uninitialised_page(data); + if (nfs_readpage_retry(task, data) != 0) + return; + } + if (unlikely(task->tk_status < 0)) + SetPageError(page); if (atomic_dec_and_test(&req->wb_complete)) { if (!PageError(page)) SetPageUptodate(page); @@ -496,25 +539,13 @@ static void nfs_readpage_set_pages_uptodate(struct nfs_read_data *data) count += base; for (;count >= PAGE_CACHE_SIZE; count -= PAGE_CACHE_SIZE, pages++) SetPageUptodate(*pages); - if (count != 0) + if (count == 0) + return; + /* Was this a short read? */ + if (data->res.eof || data->res.count == data->args.count) SetPageUptodate(*pages); } -static void nfs_readpage_set_pages_error(struct nfs_read_data *data) -{ - unsigned int count = data->args.count; - unsigned int base = data->args.pgbase; - struct page **pages; - - pages = &data->args.pages[base >> PAGE_CACHE_SHIFT]; - base &= ~PAGE_CACHE_MASK; - count += base; - for (;count >= PAGE_CACHE_SIZE; count -= PAGE_CACHE_SIZE, pages++) - SetPageError(*pages); - if (count != 0) - SetPageError(*pages); -} - /* * This is the callback from RPC telling us whether a reply was * received or some error occurred (timeout or socket shutdown). @@ -523,19 +554,20 @@ static void nfs_readpage_result_full(struct rpc_task *task, void *calldata) { struct nfs_read_data *data = calldata; + if (nfs_readpage_result(task, data) != 0) + return; /* - * Note: nfs_readpage_result may change the values of + * Note: nfs_readpage_retry may change the values of * data->args. In the multi-page case, we therefore need - * to ensure that we call the next nfs_readpage_set_page_uptodate() - * first in the multi-page case. + * to ensure that we call nfs_readpage_set_pages_uptodate() + * first. */ if (likely(task->tk_status >= 0)) { nfs_readpage_truncate_uninitialised_page(data); nfs_readpage_set_pages_uptodate(data); - } else - nfs_readpage_set_pages_error(data); - if (nfs_readpage_result(task, data) != 0) - return; + if (nfs_readpage_retry(task, data) != 0) + return; + } while (!list_empty(&data->pages)) { struct nfs_page *req = nfs_list_entry(data->pages.next); @@ -550,50 +582,6 @@ static const struct rpc_call_ops nfs_read_full_ops = { }; /* - * This is the callback from RPC telling us whether a reply was - * received or some error occurred (timeout or socket shutdown). - */ -int nfs_readpage_result(struct rpc_task *task, struct nfs_read_data *data) -{ - struct nfs_readargs *argp = &data->args; - struct nfs_readres *resp = &data->res; - int status; - - dprintk("NFS: %4d nfs_readpage_result, (status %d)\n", - task->tk_pid, task->tk_status); - - status = NFS_PROTO(data->inode)->read_done(task, data); - if (status != 0) - return status; - - nfs_add_stats(data->inode, NFSIOS_SERVERREADBYTES, resp->count); - - if (task->tk_status < 0) { - if (task->tk_status == -ESTALE) { - set_bit(NFS_INO_STALE, &NFS_FLAGS(data->inode)); - nfs_mark_for_revalidate(data->inode); - } - } else if (resp->count < argp->count && !resp->eof) { - /* This is a short read! */ - nfs_inc_stats(data->inode, NFSIOS_SHORTREAD); - /* Has the server at least made some progress? */ - if (resp->count != 0) { - /* Yes, so retry the read at the end of the data */ - argp->offset += resp->count; - argp->pgbase += resp->count; - argp->count -= resp->count; - rpc_restart_call(task); - return -EAGAIN; - } - task->tk_status = -EIO; - } - spin_lock(&data->inode->i_lock); - NFS_I(data->inode)->cache_validity |= NFS_INO_INVALID_ATIME; - spin_unlock(&data->inode->i_lock); - return 0; -} - -/* * Read a page over NFS. * We read the page synchronously in the following case: * - The error flag is set for this page. This happens only when a @@ -626,9 +614,10 @@ int nfs_readpage(struct file *file, struct page *page) goto out_error; if (file == NULL) { + error = -EBADF; ctx = nfs_find_open_context(inode, NULL, FMODE_READ); if (ctx == NULL) - return -EBADF; + goto out_error; } else ctx = get_nfs_open_context((struct nfs_open_context *) file->private_data); @@ -663,7 +652,7 @@ readpage_async_filler(void *data, struct page *page) unsigned int len; nfs_wb_page(inode, page); - len = nfs_page_length(inode, page); + len = nfs_page_length(page); if (len == 0) return nfs_return_empty_page(page); new = nfs_create_request(desc->ctx, inode, page, 0, len); |