diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c index 77966ecb0a2..86c154bad5d 100644 --- a/fs/nfs/pnfs.c +++ b/fs/nfs/pnfs.c @@ -30,6 +30,7 @@ #include #include "internal.h" #include "pnfs.h" +#include "iostat.h" #define NFSDBG_FACILITY NFSDBG_PNFS @@ -879,6 +880,33 @@ pnfs_pageio_init_read(struct nfs_pageio_descriptor *pgio, struct inode *inode) pgio->pg_test = (ld && ld->pg_test) ? pnfs_read_pg_test : NULL; } +/* + * Call the appropriate parallel I/O subsystem read function. + */ +enum pnfs_try_status +pnfs_try_to_read_data(struct nfs_read_data *rdata, + const struct rpc_call_ops *call_ops) +{ + struct inode *inode = rdata->inode; + struct nfs_server *nfss = NFS_SERVER(inode); + enum pnfs_try_status trypnfs; + + rdata->mds_ops = call_ops; + + dprintk("%s: Reading ino:%lu %u@%llu\n", + __func__, inode->i_ino, rdata->args.count, rdata->args.offset); + + trypnfs = nfss->pnfs_curr_ld->read_pagelist(rdata); + if (trypnfs == PNFS_NOT_ATTEMPTED) { + put_lseg(rdata->lseg); + rdata->lseg = NULL; + } else { + nfs_inc_stats(inode, NFSIOS_PNFS_READ); + } + dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs); + return trypnfs; +} + /* * Device ID cache. Currently supports one layout type per struct nfs_client. * Add layout type to the lookup key to expand to support multiple types. diff --git a/fs/nfs/pnfs.h b/fs/nfs/pnfs.h index 5107d14db48..585023fabb5 100644 --- a/fs/nfs/pnfs.h +++ b/fs/nfs/pnfs.h @@ -45,6 +45,11 @@ struct pnfs_layout_segment { struct pnfs_layout_hdr *pls_layout; }; +enum pnfs_try_status { + PNFS_ATTEMPTED = 0, + PNFS_NOT_ATTEMPTED = 1, +}; + #ifdef CONFIG_NFS_V4_1 #define LAYOUT_NFSV4_1_MODULE_PREFIX "nfs-layouttype4" @@ -70,6 +75,12 @@ struct pnfs_layoutdriver_type { /* test for nfs page cache coalescing */ int (*pg_test)(struct nfs_pageio_descriptor *, struct nfs_page *, struct nfs_page *); + + /* + * Return PNFS_ATTEMPTED to indicate the layout code has attempted + * I/O, else return PNFS_NOT_ATTEMPTED to fall back to normal NFS + */ + enum pnfs_try_status (*read_pagelist) (struct nfs_read_data *nfs_data); }; struct pnfs_layout_hdr { @@ -157,6 +168,8 @@ pnfs_update_layout(struct inode *ino, struct nfs_open_context *ctx, enum pnfs_iomode access_type); void set_pnfs_layoutdriver(struct nfs_server *, u32 id); void unset_pnfs_layoutdriver(struct nfs_server *); +enum pnfs_try_status pnfs_try_to_read_data(struct nfs_read_data *, + const struct rpc_call_ops *); void pnfs_pageio_init_read(struct nfs_pageio_descriptor *, struct inode *); int pnfs_layout_process(struct nfs4_layoutget *lgp); void pnfs_free_lseg_list(struct list_head *tmp_list); @@ -227,6 +240,13 @@ pnfs_update_layout(struct inode *ino, struct nfs_open_context *ctx, return NULL; } +static inline enum pnfs_try_status +pnfs_try_to_read_data(struct nfs_read_data *data, + const struct rpc_call_ops *call_ops) +{ + return PNFS_NOT_ATTEMPTED; +} + static inline bool pnfs_roc(struct inode *ino) { diff --git a/fs/nfs/read.c b/fs/nfs/read.c index 6dc9eaf00e5..4127a1c0eec 100644 --- a/fs/nfs/read.c +++ b/fs/nfs/read.c @@ -18,6 +18,8 @@ #include #include #include +#include +#include #include #include "pnfs.h" @@ -155,6 +157,45 @@ static void nfs_readpage_release(struct nfs_page *req) nfs_release_request(req); } +static int nfs_initiate_read(struct nfs_read_data *data, struct rpc_clnt *clnt, + const struct rpc_call_ops *call_ops) +{ + 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 = data->cred, + }; + struct rpc_task_setup task_setup_data = { + .task = &data->task, + .rpc_client = clnt, + .rpc_message = &msg, + .callback_ops = call_ops, + .callback_data = data, + .workqueue = nfsiod_workqueue, + .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; +} + /* * Set up the NFS read request struct */ @@ -164,26 +205,10 @@ static int nfs_read_rpcsetup(struct nfs_page *req, struct nfs_read_data *data, struct pnfs_layout_segment *lseg) { struct inode *inode = req->wb_context->path.dentry->d_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, - }; - struct rpc_task_setup task_setup_data = { - .task = &data->task, - .rpc_client = NFS_CLIENT(inode), - .rpc_message = &msg, - .callback_ops = call_ops, - .callback_data = data, - .workqueue = nfsiod_workqueue, - .flags = RPC_TASK_ASYNC | swap_flags, - }; data->req = req; data->inode = inode; - data->cred = msg.rpc_cred; + data->cred = req->wb_context->cred; data->lseg = get_lseg(lseg); data->args.fh = NFS_FH(inode); @@ -199,21 +224,11 @@ static int nfs_read_rpcsetup(struct nfs_page *req, struct nfs_read_data *data, data->res.eof = 0; nfs_fattr_init(&data->fattr); - /* Set up the initial task struct. */ - NFS_PROTO(inode)->read_setup(data, &msg); + if (data->lseg && + (pnfs_try_to_read_data(data, call_ops) == PNFS_ATTEMPTED)) + return 0; - 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); - - task = rpc_run_task(&task_setup_data); - if (IS_ERR(task)) - return PTR_ERR(task); - rpc_put_task(task); - return 0; + return nfs_initiate_read(data, NFS_CLIENT(inode), call_ops); } static void diff --git a/include/linux/nfs_iostat.h b/include/linux/nfs_iostat.h index 68b10f5f890..37a143732d0 100644 --- a/include/linux/nfs_iostat.h +++ b/include/linux/nfs_iostat.h @@ -113,6 +113,7 @@ enum nfs_stat_eventcounters { NFSIOS_SHORTREAD, NFSIOS_SHORTWRITE, NFSIOS_DELAY, + NFSIOS_PNFS_READ, __NFSIOS_COUNTSMAX, }; diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h index 560923e2872..9d2b9dae277 100644 --- a/include/linux/nfs_xdr.h +++ b/include/linux/nfs_xdr.h @@ -1018,6 +1018,7 @@ struct nfs_read_data { struct nfs_readres res; unsigned long timestamp; /* For lease renewal */ struct pnfs_layout_segment *lseg; + const struct rpc_call_ops *mds_ops; struct page *page_array[NFS_PAGEVEC_SIZE]; };