Merge tag 'split-asm_system_h-for-linus-20120328' of git://git.kernel.org/pub/scm...
[linux-2.6.git] / fs / nfs / read.c
index 6dc9eaf..9a0e8ef 100644 (file)
@@ -18,8 +18,8 @@
 #include <linux/sunrpc/clnt.h>
 #include <linux/nfs_fs.h>
 #include <linux/nfs_page.h>
+#include <linux/module.h>
 
-#include <asm/system.h>
 #include "pnfs.h"
 
 #include "nfs4_fs.h"
 
 #define NFSDBG_FACILITY                NFSDBG_PAGECACHE
 
-static int nfs_pagein_multi(struct inode *, struct list_head *, unsigned int, size_t, int, struct pnfs_layout_segment *);
-static int nfs_pagein_one(struct inode *, struct list_head *, unsigned int, size_t, int, struct pnfs_layout_segment *);
+static const struct nfs_pageio_ops nfs_pageio_read_ops;
 static const struct rpc_call_ops nfs_read_partial_ops;
 static const struct rpc_call_ops nfs_read_full_ops;
 
 static struct kmem_cache *nfs_rdata_cachep;
-static mempool_t *nfs_rdata_mempool;
-
-#define MIN_POOL_READ  (32)
 
 struct nfs_read_data *nfs_readdata_alloc(unsigned int pagecount)
 {
-       struct nfs_read_data *p = mempool_alloc(nfs_rdata_mempool, GFP_KERNEL);
+       struct nfs_read_data *p;
 
+       p = kmem_cache_zalloc(nfs_rdata_cachep, GFP_KERNEL);
        if (p) {
-               memset(p, 0, sizeof(*p));
                INIT_LIST_HEAD(&p->pages);
                p->npages = pagecount;
                if (pagecount <= ARRAY_SIZE(p->page_array))
@@ -52,7 +48,7 @@ struct nfs_read_data *nfs_readdata_alloc(unsigned int pagecount)
                else {
                        p->pagevec = kcalloc(pagecount, sizeof(struct page *), GFP_KERNEL);
                        if (!p->pagevec) {
-                               mempool_free(p, nfs_rdata_mempool);
+                               kmem_cache_free(nfs_rdata_cachep, p);
                                p = NULL;
                        }
                }
@@ -64,12 +60,11 @@ void nfs_readdata_free(struct nfs_read_data *p)
 {
        if (p && (p->pagevec != &p->page_array[0]))
                kfree(p->pagevec);
-       mempool_free(p, nfs_rdata_mempool);
+       kmem_cache_free(nfs_rdata_cachep, p);
 }
 
-static void nfs_readdata_release(struct nfs_read_data *rdata)
+void nfs_readdata_release(struct nfs_read_data *rdata)
 {
-       put_lseg(rdata->lseg);
        put_nfs_open_context(rdata->args.context);
        nfs_readdata_free(rdata);
 }
@@ -112,12 +107,33 @@ static void nfs_readpage_truncate_uninitialised_page(struct nfs_read_data *data)
        }
 }
 
+void nfs_pageio_init_read_mds(struct nfs_pageio_descriptor *pgio,
+               struct inode *inode)
+{
+       nfs_pageio_init(pgio, inode, &nfs_pageio_read_ops,
+                       NFS_SERVER(inode)->rsize, 0);
+}
+
+void nfs_pageio_reset_read_mds(struct nfs_pageio_descriptor *pgio)
+{
+       pgio->pg_ops = &nfs_pageio_read_ops;
+       pgio->pg_bsize = NFS_SERVER(pgio->pg_inode)->rsize;
+}
+EXPORT_SYMBOL_GPL(nfs_pageio_reset_read_mds);
+
+static void nfs_pageio_init_read(struct nfs_pageio_descriptor *pgio,
+               struct inode *inode)
+{
+       if (!pnfs_pageio_init_read(pgio, inode))
+               nfs_pageio_init_read_mds(pgio, inode);
+}
+
 int nfs_readpage_async(struct nfs_open_context *ctx, struct inode *inode,
                       struct page *page)
 {
-       LIST_HEAD(one_request);
        struct nfs_page *new;
        unsigned int len;
+       struct nfs_pageio_descriptor pgio;
 
        len = nfs_page_length(page);
        if (len == 0)
@@ -130,17 +146,15 @@ int nfs_readpage_async(struct nfs_open_context *ctx, struct inode *inode,
        if (len < PAGE_CACHE_SIZE)
                zero_user_segment(page, len, PAGE_CACHE_SIZE);
 
-       nfs_list_add_request(new, &one_request);
-       if (NFS_SERVER(inode)->rsize < PAGE_CACHE_SIZE)
-               nfs_pagein_multi(inode, &one_request, 1, len, 0, NULL);
-       else
-               nfs_pagein_one(inode, &one_request, 1, len, 0, NULL);
+       nfs_pageio_init_read(&pgio, inode);
+       nfs_pageio_add_request(&pgio, new);
+       nfs_pageio_complete(&pgio);
        return 0;
 }
 
 static void nfs_readpage_release(struct nfs_page *req)
 {
-       struct inode *d_inode = req->wb_context->path.dentry->d_inode;
+       struct inode *d_inode = req->wb_context->dentry->d_inode;
 
        if (PageUptodate(req->wb_page))
                nfs_readpage_to_fscache(d_inode, req->wb_page, 0);
@@ -148,32 +162,27 @@ static void nfs_readpage_release(struct nfs_page *req)
        unlock_page(req->wb_page);
 
        dprintk("NFS: read done (%s/%Ld %d@%Ld)\n",
-                       req->wb_context->path.dentry->d_inode->i_sb->s_id,
-                       (long long)NFS_FILEID(req->wb_context->path.dentry->d_inode),
+                       req->wb_context->dentry->d_inode->i_sb->s_id,
+                       (long long)NFS_FILEID(req->wb_context->dentry->d_inode),
                        req->wb_bytes,
                        (long long)req_offset(req));
        nfs_release_request(req);
 }
 
-/*
- * Set up the NFS read request struct
- */
-static int nfs_read_rpcsetup(struct nfs_page *req, struct nfs_read_data *data,
-               const struct rpc_call_ops *call_ops,
-               unsigned int count, unsigned int offset,
-               struct pnfs_layout_segment *lseg)
+int nfs_initiate_read(struct nfs_read_data *data, struct rpc_clnt *clnt,
+                     const struct rpc_call_ops *call_ops)
 {
-       struct inode *inode = req->wb_context->path.dentry->d_inode;
+       struct inode *inode = data->inode;
        int swap_flags = IS_SWAPFILE(inode) ? NFS_RPC_SWAPFLAGS : 0;
        struct rpc_task *task;
        struct rpc_message msg = {
                .rpc_argp = &data->args,
                .rpc_resp = &data->res,
-               .rpc_cred = req->wb_context->cred,
+               .rpc_cred = data->cred,
        };
        struct rpc_task_setup task_setup_data = {
                .task = &data->task,
-               .rpc_client = NFS_CLIENT(inode),
+               .rpc_client = clnt,
                .rpc_message = &msg,
                .callback_ops = call_ops,
                .callback_data = data,
@@ -181,10 +190,36 @@ static int nfs_read_rpcsetup(struct nfs_page *req, struct nfs_read_data *data,
                .flags = RPC_TASK_ASYNC | swap_flags,
        };
 
+       /* Set up the initial task struct. */
+       NFS_PROTO(inode)->read_setup(data, &msg);
+
+       dprintk("NFS: %5u initiated read call (req %s/%lld, %u bytes @ "
+                       "offset %llu)\n",
+                       data->task.tk_pid,
+                       inode->i_sb->s_id,
+                       (long long)NFS_FILEID(inode),
+                       data->args.count,
+                       (unsigned long long)data->args.offset);
+
+       task = rpc_run_task(&task_setup_data);
+       if (IS_ERR(task))
+               return PTR_ERR(task);
+       rpc_put_task(task);
+       return 0;
+}
+EXPORT_SYMBOL_GPL(nfs_initiate_read);
+
+/*
+ * Set up the NFS read request struct
+ */
+static void nfs_read_rpcsetup(struct nfs_page *req, struct nfs_read_data *data,
+               unsigned int count, unsigned int offset)
+{
+       struct inode *inode = req->wb_context->dentry->d_inode;
+
        data->req         = req;
        data->inode       = inode;
-       data->cred        = msg.rpc_cred;
-       data->lseg        = get_lseg(lseg);
+       data->cred        = req->wb_context->cred;
 
        data->args.fh     = NFS_FH(inode);
        data->args.offset = req_offset(req) + offset;
@@ -198,22 +233,34 @@ static int nfs_read_rpcsetup(struct nfs_page *req, struct nfs_read_data *data,
        data->res.count   = count;
        data->res.eof     = 0;
        nfs_fattr_init(&data->fattr);
+}
 
-       /* Set up the initial task struct. */
-       NFS_PROTO(inode)->read_setup(data, &msg);
+static int nfs_do_read(struct nfs_read_data *data,
+               const struct rpc_call_ops *call_ops)
+{
+       struct inode *inode = data->args.context->dentry->d_inode;
 
-       dprintk("NFS: %5u initiated read call (req %s/%Ld, %u bytes @ offset %Lu)\n",
-                       data->task.tk_pid,
-                       inode->i_sb->s_id,
-                       (long long)NFS_FILEID(inode),
-                       count,
-                       (unsigned long long)data->args.offset);
+       return nfs_initiate_read(data, NFS_CLIENT(inode), call_ops);
+}
 
-       task = rpc_run_task(&task_setup_data);
-       if (IS_ERR(task))
-               return PTR_ERR(task);
-       rpc_put_task(task);
-       return 0;
+static int
+nfs_do_multiple_reads(struct list_head *head,
+               const struct rpc_call_ops *call_ops)
+{
+       struct nfs_read_data *data;
+       int ret = 0;
+
+       while (!list_empty(head)) {
+               int ret2;
+
+               data = list_entry(head->next, struct nfs_read_data, list);
+               list_del_init(&data->list);
+
+               ret2 = nfs_do_read(data, call_ops);
+               if (ret == 0)
+                       ret = ret2;
+       }
+       return ret;
 }
 
 static void
@@ -224,7 +271,6 @@ nfs_async_read_error(struct list_head *head)
        while (!list_empty(head)) {
                req = nfs_list_entry(head->next);
                nfs_list_remove_request(req);
-               SetPageError(req->wb_page);
                nfs_readpage_release(req);
        }
 }
@@ -242,79 +288,59 @@ nfs_async_read_error(struct list_head *head)
  * won't see the new data until our attribute cache is updated.  This is more
  * or less conventional NFS client behavior.
  */
-static int nfs_pagein_multi(struct inode *inode, struct list_head *head, unsigned int npages, size_t count, int flags, struct pnfs_layout_segment *lseg)
+static int nfs_pagein_multi(struct nfs_pageio_descriptor *desc, struct list_head *res)
 {
-       struct nfs_page *req = nfs_list_entry(head->next);
+       struct nfs_page *req = nfs_list_entry(desc->pg_list.next);
        struct page *page = req->wb_page;
        struct nfs_read_data *data;
-       size_t rsize = NFS_SERVER(inode)->rsize, nbytes;
+       size_t rsize = desc->pg_bsize, nbytes;
        unsigned int offset;
        int requests = 0;
        int ret = 0;
-       LIST_HEAD(list);
 
        nfs_list_remove_request(req);
 
-       nbytes = count;
+       offset = 0;
+       nbytes = desc->pg_count;
        do {
                size_t len = min(nbytes,rsize);
 
                data = nfs_readdata_alloc(1);
                if (!data)
                        goto out_bad;
-               list_add(&data->pages, &list);
+               data->pagevec[0] = page;
+               nfs_read_rpcsetup(req, data, len, offset);
+               list_add(&data->list, res);
                requests++;
                nbytes -= len;
+               offset += len;
        } while(nbytes != 0);
        atomic_set(&req->wb_complete, requests);
-
-       /* We know lseg==NULL */
-       lseg = pnfs_update_layout(inode, req->wb_context, IOMODE_READ);
-       ClearPageError(page);
-       offset = 0;
-       nbytes = count;
-       do {
-               int ret2;
-
-               data = list_entry(list.next, struct nfs_read_data, pages);
-               list_del_init(&data->pages);
-
-               data->pagevec[0] = page;
-
-               if (nbytes < rsize)
-                       rsize = nbytes;
-               ret2 = nfs_read_rpcsetup(req, data, &nfs_read_partial_ops,
-                                        rsize, offset, lseg);
-               if (ret == 0)
-                       ret = ret2;
-               offset += rsize;
-               nbytes -= rsize;
-       } while (nbytes != 0);
-       put_lseg(lseg);
-
+       desc->pg_rpc_callops = &nfs_read_partial_ops;
        return ret;
-
 out_bad:
-       while (!list_empty(&list)) {
-               data = list_entry(list.next, struct nfs_read_data, pages);
-               list_del(&data->pages);
+       while (!list_empty(res)) {
+               data = list_entry(res->next, struct nfs_read_data, list);
+               list_del(&data->list);
                nfs_readdata_free(data);
        }
-       SetPageError(page);
        nfs_readpage_release(req);
        return -ENOMEM;
 }
 
-static int nfs_pagein_one(struct inode *inode, struct list_head *head, unsigned int npages, size_t count, int flags, struct pnfs_layout_segment *lseg)
+static int nfs_pagein_one(struct nfs_pageio_descriptor *desc, struct list_head *res)
 {
        struct nfs_page         *req;
        struct page             **pages;
        struct nfs_read_data    *data;
-       int ret = -ENOMEM;
+       struct list_head *head = &desc->pg_list;
+       int ret = 0;
 
-       data = nfs_readdata_alloc(npages);
+       data = nfs_readdata_alloc(nfs_page_array_len(desc->pg_base,
+                                                    desc->pg_count));
        if (!data) {
                nfs_async_read_error(head);
+               ret = -ENOMEM;
                goto out;
        }
 
@@ -323,19 +349,40 @@ static int nfs_pagein_one(struct inode *inode, struct list_head *head, unsigned
                req = nfs_list_entry(head->next);
                nfs_list_remove_request(req);
                nfs_list_add_request(req, &data->pages);
-               ClearPageError(req->wb_page);
                *pages++ = req->wb_page;
        }
        req = nfs_list_entry(data->pages.next);
-       if ((!lseg) && list_is_singular(&data->pages))
-               lseg = pnfs_update_layout(inode, req->wb_context, IOMODE_READ);
 
-       ret = nfs_read_rpcsetup(req, data, &nfs_read_full_ops, count, 0, lseg);
+       nfs_read_rpcsetup(req, data, desc->pg_count, 0);
+       list_add(&data->list, res);
+       desc->pg_rpc_callops = &nfs_read_full_ops;
 out:
-       put_lseg(lseg);
        return ret;
 }
 
+int nfs_generic_pagein(struct nfs_pageio_descriptor *desc, struct list_head *head)
+{
+       if (desc->pg_bsize < PAGE_CACHE_SIZE)
+               return nfs_pagein_multi(desc, head);
+       return nfs_pagein_one(desc, head);
+}
+
+static int nfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc)
+{
+       LIST_HEAD(head);
+       int ret;
+
+       ret = nfs_generic_pagein(desc, &head);
+       if (ret == 0)
+               ret = nfs_do_multiple_reads(&head, desc->pg_rpc_callops);
+       return ret;
+}
+
+static const struct nfs_pageio_ops nfs_pageio_read_ops = {
+       .pg_test = nfs_generic_pg_test,
+       .pg_doio = nfs_generic_pg_readpages,
+};
+
 /*
  * This is the callback from RPC telling us whether a reply was
  * received or some error occurred (timeout or socket shutdown).
@@ -375,10 +422,11 @@ static void nfs_readpage_retry(struct rpc_task *task, struct nfs_read_data *data
                return;
 
        /* Yes, so retry the read at the end of the data */
+       data->mds_offset += resp->count;
        argp->offset += resp->count;
        argp->pgbase += resp->count;
        argp->count -= resp->count;
-       nfs_restart_rpc(task, NFS_SERVER(data->inode)->nfs_client);
+       rpc_restart_call_prepare(task);
 }
 
 /*
@@ -405,33 +453,24 @@ static void nfs_readpage_release_partial(void *calldata)
        int status = data->task.tk_status;
 
        if (status < 0)
-               SetPageError(page);
+               set_bit(PG_PARTIAL_READ_FAILED, &req->wb_flags);
 
        if (atomic_dec_and_test(&req->wb_complete)) {
-               if (!PageError(page))
+               if (!test_bit(PG_PARTIAL_READ_FAILED, &req->wb_flags))
                        SetPageUptodate(page);
                nfs_readpage_release(req);
        }
        nfs_readdata_release(calldata);
 }
 
-#if defined(CONFIG_NFS_V4_1)
 void nfs_read_prepare(struct rpc_task *task, void *calldata)
 {
        struct nfs_read_data *data = calldata;
-
-       if (nfs4_setup_sequence(NFS_SERVER(data->inode),
-                               &data->args.seq_args, &data->res.seq_res,
-                               0, task))
-               return;
-       rpc_call_start(task);
+       NFS_PROTO(data->inode)->read_rpc_prepare(task, data);
 }
-#endif /* CONFIG_NFS_V4_1 */
 
 static const struct rpc_call_ops nfs_read_partial_ops = {
-#if defined(CONFIG_NFS_V4_1)
        .rpc_call_prepare = nfs_read_prepare,
-#endif /* CONFIG_NFS_V4_1 */
        .rpc_call_done = nfs_readpage_result_partial,
        .rpc_release = nfs_readpage_release_partial,
 };
@@ -495,9 +534,7 @@ static void nfs_readpage_release_full(void *calldata)
 }
 
 static const struct rpc_call_ops nfs_read_full_ops = {
-#if defined(CONFIG_NFS_V4_1)
        .rpc_call_prepare = nfs_read_prepare,
-#endif /* CONFIG_NFS_V4_1 */
        .rpc_call_done = nfs_readpage_result_full,
        .rpc_release = nfs_readpage_release_full,
 };
@@ -591,7 +628,6 @@ readpage_async_filler(void *data, struct page *page)
        return 0;
 out_error:
        error = PTR_ERR(new);
-       SetPageError(page);
 out_unlock:
        unlock_page(page);
        return error;
@@ -605,8 +641,6 @@ int nfs_readpages(struct file *filp, struct address_space *mapping,
                .pgio = &pgio,
        };
        struct inode *inode = mapping->host;
-       struct nfs_server *server = NFS_SERVER(inode);
-       size_t rsize = server->rsize;
        unsigned long npages;
        int ret = -ESTALE;
 
@@ -634,11 +668,7 @@ int nfs_readpages(struct file *filp, struct address_space *mapping,
        if (ret == 0)
                goto read_complete; /* all pages were read */
 
-       pnfs_pageio_init_read(&pgio, inode);
-       if (rsize < PAGE_CACHE_SIZE)
-               nfs_pageio_init(&pgio, inode, nfs_pagein_multi, rsize, 0);
-       else
-               nfs_pageio_init(&pgio, inode, nfs_pagein_one, rsize, 0);
+       nfs_pageio_init_read(&pgio, inode);
 
        ret = read_cache_pages(mapping, pages, readpage_async_filler, &desc);
 
@@ -660,16 +690,10 @@ int __init nfs_init_readpagecache(void)
        if (nfs_rdata_cachep == NULL)
                return -ENOMEM;
 
-       nfs_rdata_mempool = mempool_create_slab_pool(MIN_POOL_READ,
-                                                    nfs_rdata_cachep);
-       if (nfs_rdata_mempool == NULL)
-               return -ENOMEM;
-
        return 0;
 }
 
 void nfs_destroy_readpagecache(void)
 {
-       mempool_destroy(nfs_rdata_mempool);
        kmem_cache_destroy(nfs_rdata_cachep);
 }