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1470 lines
37 KiB
1470 lines
37 KiB
// SPDX-License-Identifier: GPL-2.0-only |
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/* |
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* linux/fs/nfs/pagelist.c |
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* |
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* A set of helper functions for managing NFS read and write requests. |
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* The main purpose of these routines is to provide support for the |
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* coalescing of several requests into a single RPC call. |
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* |
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* Copyright 2000, 2001 (c) Trond Myklebust <[email protected]> |
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* |
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*/ |
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|
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#include <linux/slab.h> |
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#include <linux/file.h> |
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#include <linux/sched.h> |
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#include <linux/sunrpc/clnt.h> |
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#include <linux/nfs.h> |
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#include <linux/nfs3.h> |
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#include <linux/nfs4.h> |
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#include <linux/nfs_fs.h> |
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#include <linux/nfs_page.h> |
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#include <linux/nfs_mount.h> |
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#include <linux/export.h> |
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|
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#include "internal.h" |
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#include "pnfs.h" |
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#include "nfstrace.h" |
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|
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#define NFSDBG_FACILITY NFSDBG_PAGECACHE |
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|
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static struct kmem_cache *nfs_page_cachep; |
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static const struct rpc_call_ops nfs_pgio_common_ops; |
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|
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static struct nfs_pgio_mirror * |
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nfs_pgio_get_mirror(struct nfs_pageio_descriptor *desc, u32 idx) |
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{ |
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if (desc->pg_ops->pg_get_mirror) |
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return desc->pg_ops->pg_get_mirror(desc, idx); |
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return &desc->pg_mirrors[0]; |
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} |
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|
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struct nfs_pgio_mirror * |
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nfs_pgio_current_mirror(struct nfs_pageio_descriptor *desc) |
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{ |
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return nfs_pgio_get_mirror(desc, desc->pg_mirror_idx); |
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} |
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EXPORT_SYMBOL_GPL(nfs_pgio_current_mirror); |
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|
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static u32 |
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nfs_pgio_set_current_mirror(struct nfs_pageio_descriptor *desc, u32 idx) |
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{ |
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if (desc->pg_ops->pg_set_mirror) |
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return desc->pg_ops->pg_set_mirror(desc, idx); |
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return desc->pg_mirror_idx; |
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} |
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|
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void nfs_pgheader_init(struct nfs_pageio_descriptor *desc, |
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struct nfs_pgio_header *hdr, |
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void (*release)(struct nfs_pgio_header *hdr)) |
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{ |
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struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc); |
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|
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|
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hdr->req = nfs_list_entry(mirror->pg_list.next); |
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hdr->inode = desc->pg_inode; |
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hdr->cred = nfs_req_openctx(hdr->req)->cred; |
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hdr->io_start = req_offset(hdr->req); |
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hdr->good_bytes = mirror->pg_count; |
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hdr->io_completion = desc->pg_io_completion; |
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hdr->dreq = desc->pg_dreq; |
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hdr->release = release; |
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hdr->completion_ops = desc->pg_completion_ops; |
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if (hdr->completion_ops->init_hdr) |
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hdr->completion_ops->init_hdr(hdr); |
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|
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hdr->pgio_mirror_idx = desc->pg_mirror_idx; |
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} |
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EXPORT_SYMBOL_GPL(nfs_pgheader_init); |
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|
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void nfs_set_pgio_error(struct nfs_pgio_header *hdr, int error, loff_t pos) |
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{ |
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unsigned int new = pos - hdr->io_start; |
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|
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trace_nfs_pgio_error(hdr, error, pos); |
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if (hdr->good_bytes > new) { |
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hdr->good_bytes = new; |
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clear_bit(NFS_IOHDR_EOF, &hdr->flags); |
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if (!test_and_set_bit(NFS_IOHDR_ERROR, &hdr->flags)) |
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hdr->error = error; |
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} |
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} |
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|
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static inline struct nfs_page * |
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nfs_page_alloc(void) |
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{ |
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struct nfs_page *p = kmem_cache_zalloc(nfs_page_cachep, GFP_KERNEL); |
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if (p) |
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INIT_LIST_HEAD(&p->wb_list); |
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return p; |
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} |
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|
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static inline void |
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nfs_page_free(struct nfs_page *p) |
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{ |
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kmem_cache_free(nfs_page_cachep, p); |
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} |
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|
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/** |
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* nfs_iocounter_wait - wait for i/o to complete |
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* @l_ctx: nfs_lock_context with io_counter to use |
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* |
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* returns -ERESTARTSYS if interrupted by a fatal signal. |
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* Otherwise returns 0 once the io_count hits 0. |
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*/ |
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int |
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nfs_iocounter_wait(struct nfs_lock_context *l_ctx) |
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{ |
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return wait_var_event_killable(&l_ctx->io_count, |
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!atomic_read(&l_ctx->io_count)); |
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} |
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|
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/** |
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* nfs_async_iocounter_wait - wait on a rpc_waitqueue for I/O |
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* to complete |
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* @task: the rpc_task that should wait |
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* @l_ctx: nfs_lock_context with io_counter to check |
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* |
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* Returns true if there is outstanding I/O to wait on and the |
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* task has been put to sleep. |
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*/ |
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bool |
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nfs_async_iocounter_wait(struct rpc_task *task, struct nfs_lock_context *l_ctx) |
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{ |
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struct inode *inode = d_inode(l_ctx->open_context->dentry); |
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bool ret = false; |
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|
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if (atomic_read(&l_ctx->io_count) > 0) { |
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rpc_sleep_on(&NFS_SERVER(inode)->uoc_rpcwaitq, task, NULL); |
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ret = true; |
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} |
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|
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if (atomic_read(&l_ctx->io_count) == 0) { |
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rpc_wake_up_queued_task(&NFS_SERVER(inode)->uoc_rpcwaitq, task); |
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ret = false; |
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} |
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|
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return ret; |
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} |
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EXPORT_SYMBOL_GPL(nfs_async_iocounter_wait); |
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|
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/* |
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* nfs_page_lock_head_request - page lock the head of the page group |
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* @req: any member of the page group |
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*/ |
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struct nfs_page * |
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nfs_page_group_lock_head(struct nfs_page *req) |
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{ |
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struct nfs_page *head = req->wb_head; |
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|
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while (!nfs_lock_request(head)) { |
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int ret = nfs_wait_on_request(head); |
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if (ret < 0) |
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return ERR_PTR(ret); |
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} |
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if (head != req) |
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kref_get(&head->wb_kref); |
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return head; |
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} |
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|
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/* |
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* nfs_unroll_locks - unlock all newly locked reqs and wait on @req |
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* @head: head request of page group, must be holding head lock |
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* @req: request that couldn't lock and needs to wait on the req bit lock |
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* |
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* This is a helper function for nfs_lock_and_join_requests |
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* returns 0 on success, < 0 on error. |
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*/ |
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static void |
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nfs_unroll_locks(struct nfs_page *head, struct nfs_page *req) |
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{ |
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struct nfs_page *tmp; |
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|
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/* relinquish all the locks successfully grabbed this run */ |
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for (tmp = head->wb_this_page ; tmp != req; tmp = tmp->wb_this_page) { |
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if (!kref_read(&tmp->wb_kref)) |
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continue; |
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nfs_unlock_and_release_request(tmp); |
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} |
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} |
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|
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/* |
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* nfs_page_group_lock_subreq - try to lock a subrequest |
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* @head: head request of page group |
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* @subreq: request to lock |
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* |
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* This is a helper function for nfs_lock_and_join_requests which |
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* must be called with the head request and page group both locked. |
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* On error, it returns with the page group unlocked. |
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*/ |
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static int |
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nfs_page_group_lock_subreq(struct nfs_page *head, struct nfs_page *subreq) |
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{ |
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int ret; |
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|
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if (!kref_get_unless_zero(&subreq->wb_kref)) |
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return 0; |
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while (!nfs_lock_request(subreq)) { |
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nfs_page_group_unlock(head); |
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ret = nfs_wait_on_request(subreq); |
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if (!ret) |
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ret = nfs_page_group_lock(head); |
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if (ret < 0) { |
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nfs_unroll_locks(head, subreq); |
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nfs_release_request(subreq); |
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return ret; |
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} |
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} |
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return 0; |
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} |
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|
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/* |
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* nfs_page_group_lock_subrequests - try to lock the subrequests |
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* @head: head request of page group |
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* |
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* This is a helper function for nfs_lock_and_join_requests which |
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* must be called with the head request locked. |
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*/ |
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int nfs_page_group_lock_subrequests(struct nfs_page *head) |
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{ |
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struct nfs_page *subreq; |
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int ret; |
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|
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ret = nfs_page_group_lock(head); |
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if (ret < 0) |
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return ret; |
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/* lock each request in the page group */ |
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for (subreq = head->wb_this_page; subreq != head; |
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subreq = subreq->wb_this_page) { |
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ret = nfs_page_group_lock_subreq(head, subreq); |
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if (ret < 0) |
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return ret; |
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} |
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nfs_page_group_unlock(head); |
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return 0; |
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} |
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|
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/* |
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* nfs_page_set_headlock - set the request PG_HEADLOCK |
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* @req: request that is to be locked |
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* |
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* this lock must be held when modifying req->wb_head |
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* |
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* return 0 on success, < 0 on error |
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*/ |
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int |
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nfs_page_set_headlock(struct nfs_page *req) |
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{ |
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if (!test_and_set_bit(PG_HEADLOCK, &req->wb_flags)) |
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return 0; |
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set_bit(PG_CONTENDED1, &req->wb_flags); |
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smp_mb__after_atomic(); |
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return wait_on_bit_lock(&req->wb_flags, PG_HEADLOCK, |
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TASK_UNINTERRUPTIBLE); |
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} |
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|
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/* |
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* nfs_page_clear_headlock - clear the request PG_HEADLOCK |
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* @req: request that is to be locked |
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*/ |
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void |
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nfs_page_clear_headlock(struct nfs_page *req) |
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{ |
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smp_mb__before_atomic(); |
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clear_bit(PG_HEADLOCK, &req->wb_flags); |
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smp_mb__after_atomic(); |
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if (!test_bit(PG_CONTENDED1, &req->wb_flags)) |
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return; |
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wake_up_bit(&req->wb_flags, PG_HEADLOCK); |
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} |
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|
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/* |
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* nfs_page_group_lock - lock the head of the page group |
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* @req: request in group that is to be locked |
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* |
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* this lock must be held when traversing or modifying the page |
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* group list |
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* |
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* return 0 on success, < 0 on error |
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*/ |
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int |
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nfs_page_group_lock(struct nfs_page *req) |
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{ |
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int ret; |
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ret = nfs_page_set_headlock(req); |
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if (ret || req->wb_head == req) |
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return ret; |
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return nfs_page_set_headlock(req->wb_head); |
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} |
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|
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/* |
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* nfs_page_group_unlock - unlock the head of the page group |
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* @req: request in group that is to be unlocked |
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*/ |
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void |
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nfs_page_group_unlock(struct nfs_page *req) |
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{ |
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if (req != req->wb_head) |
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nfs_page_clear_headlock(req->wb_head); |
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nfs_page_clear_headlock(req); |
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} |
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|
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/* |
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* nfs_page_group_sync_on_bit_locked |
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* |
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* must be called with page group lock held |
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*/ |
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static bool |
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nfs_page_group_sync_on_bit_locked(struct nfs_page *req, unsigned int bit) |
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{ |
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struct nfs_page *head = req->wb_head; |
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struct nfs_page *tmp; |
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|
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WARN_ON_ONCE(!test_bit(PG_HEADLOCK, &head->wb_flags)); |
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WARN_ON_ONCE(test_and_set_bit(bit, &req->wb_flags)); |
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tmp = req->wb_this_page; |
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while (tmp != req) { |
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if (!test_bit(bit, &tmp->wb_flags)) |
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return false; |
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tmp = tmp->wb_this_page; |
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} |
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|
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/* true! reset all bits */ |
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tmp = req; |
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do { |
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clear_bit(bit, &tmp->wb_flags); |
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tmp = tmp->wb_this_page; |
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} while (tmp != req); |
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|
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return true; |
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} |
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|
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/* |
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* nfs_page_group_sync_on_bit - set bit on current request, but only |
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* return true if the bit is set for all requests in page group |
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* @req - request in page group |
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* @bit - PG_* bit that is used to sync page group |
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*/ |
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bool nfs_page_group_sync_on_bit(struct nfs_page *req, unsigned int bit) |
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{ |
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bool ret; |
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|
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nfs_page_group_lock(req); |
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ret = nfs_page_group_sync_on_bit_locked(req, bit); |
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nfs_page_group_unlock(req); |
|
|
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return ret; |
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} |
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|
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/* |
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* nfs_page_group_init - Initialize the page group linkage for @req |
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* @req - a new nfs request |
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* @prev - the previous request in page group, or NULL if @req is the first |
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* or only request in the group (the head). |
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*/ |
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static inline void |
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nfs_page_group_init(struct nfs_page *req, struct nfs_page *prev) |
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{ |
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struct inode *inode; |
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WARN_ON_ONCE(prev == req); |
|
|
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if (!prev) { |
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/* a head request */ |
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req->wb_head = req; |
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req->wb_this_page = req; |
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} else { |
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/* a subrequest */ |
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WARN_ON_ONCE(prev->wb_this_page != prev->wb_head); |
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WARN_ON_ONCE(!test_bit(PG_HEADLOCK, &prev->wb_head->wb_flags)); |
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req->wb_head = prev->wb_head; |
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req->wb_this_page = prev->wb_this_page; |
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prev->wb_this_page = req; |
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|
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/* All subrequests take a ref on the head request until |
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* nfs_page_group_destroy is called */ |
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kref_get(&req->wb_head->wb_kref); |
|
|
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/* grab extra ref and bump the request count if head request |
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* has extra ref from the write/commit path to handle handoff |
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* between write and commit lists. */ |
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if (test_bit(PG_INODE_REF, &prev->wb_head->wb_flags)) { |
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inode = page_file_mapping(req->wb_page)->host; |
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set_bit(PG_INODE_REF, &req->wb_flags); |
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kref_get(&req->wb_kref); |
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atomic_long_inc(&NFS_I(inode)->nrequests); |
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} |
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} |
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} |
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|
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/* |
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* nfs_page_group_destroy - sync the destruction of page groups |
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* @req - request that no longer needs the page group |
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* |
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* releases the page group reference from each member once all |
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* members have called this function. |
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*/ |
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static void |
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nfs_page_group_destroy(struct kref *kref) |
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{ |
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struct nfs_page *req = container_of(kref, struct nfs_page, wb_kref); |
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struct nfs_page *head = req->wb_head; |
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struct nfs_page *tmp, *next; |
|
|
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if (!nfs_page_group_sync_on_bit(req, PG_TEARDOWN)) |
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goto out; |
|
|
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tmp = req; |
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do { |
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next = tmp->wb_this_page; |
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/* unlink and free */ |
|
tmp->wb_this_page = tmp; |
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tmp->wb_head = tmp; |
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nfs_free_request(tmp); |
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tmp = next; |
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} while (tmp != req); |
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out: |
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/* subrequests must release the ref on the head request */ |
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if (head != req) |
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nfs_release_request(head); |
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} |
|
|
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static struct nfs_page * |
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__nfs_create_request(struct nfs_lock_context *l_ctx, struct page *page, |
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unsigned int pgbase, unsigned int offset, |
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unsigned int count) |
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{ |
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struct nfs_page *req; |
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struct nfs_open_context *ctx = l_ctx->open_context; |
|
|
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if (test_bit(NFS_CONTEXT_BAD, &ctx->flags)) |
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return ERR_PTR(-EBADF); |
|
/* try to allocate the request struct */ |
|
req = nfs_page_alloc(); |
|
if (req == NULL) |
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return ERR_PTR(-ENOMEM); |
|
|
|
req->wb_lock_context = l_ctx; |
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refcount_inc(&l_ctx->count); |
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atomic_inc(&l_ctx->io_count); |
|
|
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/* Initialize the request struct. Initially, we assume a |
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* long write-back delay. This will be adjusted in |
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* update_nfs_request below if the region is not locked. */ |
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req->wb_page = page; |
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if (page) { |
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req->wb_index = page_index(page); |
|
get_page(page); |
|
} |
|
req->wb_offset = offset; |
|
req->wb_pgbase = pgbase; |
|
req->wb_bytes = count; |
|
kref_init(&req->wb_kref); |
|
req->wb_nio = 0; |
|
return req; |
|
} |
|
|
|
/** |
|
* nfs_create_request - Create an NFS read/write request. |
|
* @ctx: open context to use |
|
* @page: page to write |
|
* @offset: starting offset within the page for the write |
|
* @count: number of bytes to read/write |
|
* |
|
* The page must be locked by the caller. This makes sure we never |
|
* create two different requests for the same page. |
|
* User should ensure it is safe to sleep in this function. |
|
*/ |
|
struct nfs_page * |
|
nfs_create_request(struct nfs_open_context *ctx, struct page *page, |
|
unsigned int offset, unsigned int count) |
|
{ |
|
struct nfs_lock_context *l_ctx = nfs_get_lock_context(ctx); |
|
struct nfs_page *ret; |
|
|
|
if (IS_ERR(l_ctx)) |
|
return ERR_CAST(l_ctx); |
|
ret = __nfs_create_request(l_ctx, page, offset, offset, count); |
|
if (!IS_ERR(ret)) |
|
nfs_page_group_init(ret, NULL); |
|
nfs_put_lock_context(l_ctx); |
|
return ret; |
|
} |
|
|
|
static struct nfs_page * |
|
nfs_create_subreq(struct nfs_page *req, |
|
unsigned int pgbase, |
|
unsigned int offset, |
|
unsigned int count) |
|
{ |
|
struct nfs_page *last; |
|
struct nfs_page *ret; |
|
|
|
ret = __nfs_create_request(req->wb_lock_context, req->wb_page, |
|
pgbase, offset, count); |
|
if (!IS_ERR(ret)) { |
|
/* find the last request */ |
|
for (last = req->wb_head; |
|
last->wb_this_page != req->wb_head; |
|
last = last->wb_this_page) |
|
; |
|
|
|
nfs_lock_request(ret); |
|
ret->wb_index = req->wb_index; |
|
nfs_page_group_init(ret, last); |
|
ret->wb_nio = req->wb_nio; |
|
} |
|
return ret; |
|
} |
|
|
|
/** |
|
* nfs_unlock_request - Unlock request and wake up sleepers. |
|
* @req: pointer to request |
|
*/ |
|
void nfs_unlock_request(struct nfs_page *req) |
|
{ |
|
if (!NFS_WBACK_BUSY(req)) { |
|
printk(KERN_ERR "NFS: Invalid unlock attempted\n"); |
|
BUG(); |
|
} |
|
smp_mb__before_atomic(); |
|
clear_bit(PG_BUSY, &req->wb_flags); |
|
smp_mb__after_atomic(); |
|
if (!test_bit(PG_CONTENDED2, &req->wb_flags)) |
|
return; |
|
wake_up_bit(&req->wb_flags, PG_BUSY); |
|
} |
|
|
|
/** |
|
* nfs_unlock_and_release_request - Unlock request and release the nfs_page |
|
* @req: pointer to request |
|
*/ |
|
void nfs_unlock_and_release_request(struct nfs_page *req) |
|
{ |
|
nfs_unlock_request(req); |
|
nfs_release_request(req); |
|
} |
|
|
|
/* |
|
* nfs_clear_request - Free up all resources allocated to the request |
|
* @req: |
|
* |
|
* Release page and open context resources associated with a read/write |
|
* request after it has completed. |
|
*/ |
|
static void nfs_clear_request(struct nfs_page *req) |
|
{ |
|
struct page *page = req->wb_page; |
|
struct nfs_lock_context *l_ctx = req->wb_lock_context; |
|
struct nfs_open_context *ctx; |
|
|
|
if (page != NULL) { |
|
put_page(page); |
|
req->wb_page = NULL; |
|
} |
|
if (l_ctx != NULL) { |
|
if (atomic_dec_and_test(&l_ctx->io_count)) { |
|
wake_up_var(&l_ctx->io_count); |
|
ctx = l_ctx->open_context; |
|
if (test_bit(NFS_CONTEXT_UNLOCK, &ctx->flags)) |
|
rpc_wake_up(&NFS_SERVER(d_inode(ctx->dentry))->uoc_rpcwaitq); |
|
} |
|
nfs_put_lock_context(l_ctx); |
|
req->wb_lock_context = NULL; |
|
} |
|
} |
|
|
|
/** |
|
* nfs_release_request - Release the count on an NFS read/write request |
|
* @req: request to release |
|
* |
|
* Note: Should never be called with the spinlock held! |
|
*/ |
|
void nfs_free_request(struct nfs_page *req) |
|
{ |
|
WARN_ON_ONCE(req->wb_this_page != req); |
|
|
|
/* extra debug: make sure no sync bits are still set */ |
|
WARN_ON_ONCE(test_bit(PG_TEARDOWN, &req->wb_flags)); |
|
WARN_ON_ONCE(test_bit(PG_UNLOCKPAGE, &req->wb_flags)); |
|
WARN_ON_ONCE(test_bit(PG_UPTODATE, &req->wb_flags)); |
|
WARN_ON_ONCE(test_bit(PG_WB_END, &req->wb_flags)); |
|
WARN_ON_ONCE(test_bit(PG_REMOVE, &req->wb_flags)); |
|
|
|
/* Release struct file and open context */ |
|
nfs_clear_request(req); |
|
nfs_page_free(req); |
|
} |
|
|
|
void nfs_release_request(struct nfs_page *req) |
|
{ |
|
kref_put(&req->wb_kref, nfs_page_group_destroy); |
|
} |
|
EXPORT_SYMBOL_GPL(nfs_release_request); |
|
|
|
/** |
|
* nfs_wait_on_request - Wait for a request to complete. |
|
* @req: request to wait upon. |
|
* |
|
* Interruptible by fatal signals only. |
|
* The user is responsible for holding a count on the request. |
|
*/ |
|
int |
|
nfs_wait_on_request(struct nfs_page *req) |
|
{ |
|
if (!test_bit(PG_BUSY, &req->wb_flags)) |
|
return 0; |
|
set_bit(PG_CONTENDED2, &req->wb_flags); |
|
smp_mb__after_atomic(); |
|
return wait_on_bit_io(&req->wb_flags, PG_BUSY, |
|
TASK_UNINTERRUPTIBLE); |
|
} |
|
EXPORT_SYMBOL_GPL(nfs_wait_on_request); |
|
|
|
/* |
|
* nfs_generic_pg_test - determine if requests can be coalesced |
|
* @desc: pointer to descriptor |
|
* @prev: previous request in desc, or NULL |
|
* @req: this request |
|
* |
|
* Returns zero if @req cannot be coalesced into @desc, otherwise it returns |
|
* the size of the request. |
|
*/ |
|
size_t nfs_generic_pg_test(struct nfs_pageio_descriptor *desc, |
|
struct nfs_page *prev, struct nfs_page *req) |
|
{ |
|
struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc); |
|
|
|
|
|
if (mirror->pg_count > mirror->pg_bsize) { |
|
/* should never happen */ |
|
WARN_ON_ONCE(1); |
|
return 0; |
|
} |
|
|
|
/* |
|
* Limit the request size so that we can still allocate a page array |
|
* for it without upsetting the slab allocator. |
|
*/ |
|
if (((mirror->pg_count + req->wb_bytes) >> PAGE_SHIFT) * |
|
sizeof(struct page *) > PAGE_SIZE) |
|
return 0; |
|
|
|
return min(mirror->pg_bsize - mirror->pg_count, (size_t)req->wb_bytes); |
|
} |
|
EXPORT_SYMBOL_GPL(nfs_generic_pg_test); |
|
|
|
struct nfs_pgio_header *nfs_pgio_header_alloc(const struct nfs_rw_ops *ops) |
|
{ |
|
struct nfs_pgio_header *hdr = ops->rw_alloc_header(); |
|
|
|
if (hdr) { |
|
INIT_LIST_HEAD(&hdr->pages); |
|
hdr->rw_ops = ops; |
|
} |
|
return hdr; |
|
} |
|
EXPORT_SYMBOL_GPL(nfs_pgio_header_alloc); |
|
|
|
/** |
|
* nfs_pgio_data_destroy - make @hdr suitable for reuse |
|
* |
|
* Frees memory and releases refs from nfs_generic_pgio, so that it may |
|
* be called again. |
|
* |
|
* @hdr: A header that has had nfs_generic_pgio called |
|
*/ |
|
static void nfs_pgio_data_destroy(struct nfs_pgio_header *hdr) |
|
{ |
|
if (hdr->args.context) |
|
put_nfs_open_context(hdr->args.context); |
|
if (hdr->page_array.pagevec != hdr->page_array.page_array) |
|
kfree(hdr->page_array.pagevec); |
|
} |
|
|
|
/* |
|
* nfs_pgio_header_free - Free a read or write header |
|
* @hdr: The header to free |
|
*/ |
|
void nfs_pgio_header_free(struct nfs_pgio_header *hdr) |
|
{ |
|
nfs_pgio_data_destroy(hdr); |
|
hdr->rw_ops->rw_free_header(hdr); |
|
} |
|
EXPORT_SYMBOL_GPL(nfs_pgio_header_free); |
|
|
|
/** |
|
* nfs_pgio_rpcsetup - Set up arguments for a pageio call |
|
* @hdr: The pageio hdr |
|
* @count: Number of bytes to read |
|
* @how: How to commit data (writes only) |
|
* @cinfo: Commit information for the call (writes only) |
|
*/ |
|
static void nfs_pgio_rpcsetup(struct nfs_pgio_header *hdr, |
|
unsigned int count, |
|
int how, struct nfs_commit_info *cinfo) |
|
{ |
|
struct nfs_page *req = hdr->req; |
|
|
|
/* Set up the RPC argument and reply structs |
|
* NB: take care not to mess about with hdr->commit et al. */ |
|
|
|
hdr->args.fh = NFS_FH(hdr->inode); |
|
hdr->args.offset = req_offset(req); |
|
/* pnfs_set_layoutcommit needs this */ |
|
hdr->mds_offset = hdr->args.offset; |
|
hdr->args.pgbase = req->wb_pgbase; |
|
hdr->args.pages = hdr->page_array.pagevec; |
|
hdr->args.count = count; |
|
hdr->args.context = get_nfs_open_context(nfs_req_openctx(req)); |
|
hdr->args.lock_context = req->wb_lock_context; |
|
hdr->args.stable = NFS_UNSTABLE; |
|
switch (how & (FLUSH_STABLE | FLUSH_COND_STABLE)) { |
|
case 0: |
|
break; |
|
case FLUSH_COND_STABLE: |
|
if (nfs_reqs_to_commit(cinfo)) |
|
break; |
|
fallthrough; |
|
default: |
|
hdr->args.stable = NFS_FILE_SYNC; |
|
} |
|
|
|
hdr->res.fattr = &hdr->fattr; |
|
hdr->res.count = 0; |
|
hdr->res.eof = 0; |
|
hdr->res.verf = &hdr->verf; |
|
nfs_fattr_init(&hdr->fattr); |
|
} |
|
|
|
/** |
|
* nfs_pgio_prepare - Prepare pageio hdr to go over the wire |
|
* @task: The current task |
|
* @calldata: pageio header to prepare |
|
*/ |
|
static void nfs_pgio_prepare(struct rpc_task *task, void *calldata) |
|
{ |
|
struct nfs_pgio_header *hdr = calldata; |
|
int err; |
|
err = NFS_PROTO(hdr->inode)->pgio_rpc_prepare(task, hdr); |
|
if (err) |
|
rpc_exit(task, err); |
|
} |
|
|
|
int nfs_initiate_pgio(struct rpc_clnt *clnt, struct nfs_pgio_header *hdr, |
|
const struct cred *cred, const struct nfs_rpc_ops *rpc_ops, |
|
const struct rpc_call_ops *call_ops, int how, int flags) |
|
{ |
|
struct rpc_task *task; |
|
struct rpc_message msg = { |
|
.rpc_argp = &hdr->args, |
|
.rpc_resp = &hdr->res, |
|
.rpc_cred = cred, |
|
}; |
|
struct rpc_task_setup task_setup_data = { |
|
.rpc_client = clnt, |
|
.task = &hdr->task, |
|
.rpc_message = &msg, |
|
.callback_ops = call_ops, |
|
.callback_data = hdr, |
|
.workqueue = nfsiod_workqueue, |
|
.flags = RPC_TASK_ASYNC | flags, |
|
}; |
|
|
|
hdr->rw_ops->rw_initiate(hdr, &msg, rpc_ops, &task_setup_data, how); |
|
|
|
dprintk("NFS: initiated pgio call " |
|
"(req %s/%llu, %u bytes @ offset %llu)\n", |
|
hdr->inode->i_sb->s_id, |
|
(unsigned long long)NFS_FILEID(hdr->inode), |
|
hdr->args.count, |
|
(unsigned long long)hdr->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_pgio); |
|
|
|
/** |
|
* nfs_pgio_error - Clean up from a pageio error |
|
* @hdr: pageio header |
|
*/ |
|
static void nfs_pgio_error(struct nfs_pgio_header *hdr) |
|
{ |
|
set_bit(NFS_IOHDR_REDO, &hdr->flags); |
|
hdr->completion_ops->completion(hdr); |
|
} |
|
|
|
/** |
|
* nfs_pgio_release - Release pageio data |
|
* @calldata: The pageio header to release |
|
*/ |
|
static void nfs_pgio_release(void *calldata) |
|
{ |
|
struct nfs_pgio_header *hdr = calldata; |
|
hdr->completion_ops->completion(hdr); |
|
} |
|
|
|
static void nfs_pageio_mirror_init(struct nfs_pgio_mirror *mirror, |
|
unsigned int bsize) |
|
{ |
|
INIT_LIST_HEAD(&mirror->pg_list); |
|
mirror->pg_bytes_written = 0; |
|
mirror->pg_count = 0; |
|
mirror->pg_bsize = bsize; |
|
mirror->pg_base = 0; |
|
mirror->pg_recoalesce = 0; |
|
} |
|
|
|
/** |
|
* nfs_pageio_init - initialise a page io descriptor |
|
* @desc: pointer to descriptor |
|
* @inode: pointer to inode |
|
* @pg_ops: pointer to pageio operations |
|
* @compl_ops: pointer to pageio completion operations |
|
* @rw_ops: pointer to nfs read/write operations |
|
* @bsize: io block size |
|
* @io_flags: extra parameters for the io function |
|
*/ |
|
void nfs_pageio_init(struct nfs_pageio_descriptor *desc, |
|
struct inode *inode, |
|
const struct nfs_pageio_ops *pg_ops, |
|
const struct nfs_pgio_completion_ops *compl_ops, |
|
const struct nfs_rw_ops *rw_ops, |
|
size_t bsize, |
|
int io_flags) |
|
{ |
|
desc->pg_moreio = 0; |
|
desc->pg_inode = inode; |
|
desc->pg_ops = pg_ops; |
|
desc->pg_completion_ops = compl_ops; |
|
desc->pg_rw_ops = rw_ops; |
|
desc->pg_ioflags = io_flags; |
|
desc->pg_error = 0; |
|
desc->pg_lseg = NULL; |
|
desc->pg_io_completion = NULL; |
|
desc->pg_dreq = NULL; |
|
desc->pg_bsize = bsize; |
|
|
|
desc->pg_mirror_count = 1; |
|
desc->pg_mirror_idx = 0; |
|
|
|
desc->pg_mirrors_dynamic = NULL; |
|
desc->pg_mirrors = desc->pg_mirrors_static; |
|
nfs_pageio_mirror_init(&desc->pg_mirrors[0], bsize); |
|
desc->pg_maxretrans = 0; |
|
} |
|
|
|
/** |
|
* nfs_pgio_result - Basic pageio error handling |
|
* @task: The task that ran |
|
* @calldata: Pageio header to check |
|
*/ |
|
static void nfs_pgio_result(struct rpc_task *task, void *calldata) |
|
{ |
|
struct nfs_pgio_header *hdr = calldata; |
|
struct inode *inode = hdr->inode; |
|
|
|
dprintk("NFS: %s: %5u, (status %d)\n", __func__, |
|
task->tk_pid, task->tk_status); |
|
|
|
if (hdr->rw_ops->rw_done(task, hdr, inode) != 0) |
|
return; |
|
if (task->tk_status < 0) |
|
nfs_set_pgio_error(hdr, task->tk_status, hdr->args.offset); |
|
else |
|
hdr->rw_ops->rw_result(task, hdr); |
|
} |
|
|
|
/* |
|
* Create an RPC task for the given read or write request and kick it. |
|
* The page must have been locked by the caller. |
|
* |
|
* It may happen that the page we're passed is not marked dirty. |
|
* This is the case if nfs_updatepage detects a conflicting request |
|
* that has been written but not committed. |
|
*/ |
|
int nfs_generic_pgio(struct nfs_pageio_descriptor *desc, |
|
struct nfs_pgio_header *hdr) |
|
{ |
|
struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc); |
|
|
|
struct nfs_page *req; |
|
struct page **pages, |
|
*last_page; |
|
struct list_head *head = &mirror->pg_list; |
|
struct nfs_commit_info cinfo; |
|
struct nfs_page_array *pg_array = &hdr->page_array; |
|
unsigned int pagecount, pageused; |
|
gfp_t gfp_flags = GFP_KERNEL; |
|
|
|
pagecount = nfs_page_array_len(mirror->pg_base, mirror->pg_count); |
|
pg_array->npages = pagecount; |
|
|
|
if (pagecount <= ARRAY_SIZE(pg_array->page_array)) |
|
pg_array->pagevec = pg_array->page_array; |
|
else { |
|
pg_array->pagevec = kcalloc(pagecount, sizeof(struct page *), gfp_flags); |
|
if (!pg_array->pagevec) { |
|
pg_array->npages = 0; |
|
nfs_pgio_error(hdr); |
|
desc->pg_error = -ENOMEM; |
|
return desc->pg_error; |
|
} |
|
} |
|
|
|
nfs_init_cinfo(&cinfo, desc->pg_inode, desc->pg_dreq); |
|
pages = hdr->page_array.pagevec; |
|
last_page = NULL; |
|
pageused = 0; |
|
while (!list_empty(head)) { |
|
req = nfs_list_entry(head->next); |
|
nfs_list_move_request(req, &hdr->pages); |
|
|
|
if (!last_page || last_page != req->wb_page) { |
|
pageused++; |
|
if (pageused > pagecount) |
|
break; |
|
*pages++ = last_page = req->wb_page; |
|
} |
|
} |
|
if (WARN_ON_ONCE(pageused != pagecount)) { |
|
nfs_pgio_error(hdr); |
|
desc->pg_error = -EINVAL; |
|
return desc->pg_error; |
|
} |
|
|
|
if ((desc->pg_ioflags & FLUSH_COND_STABLE) && |
|
(desc->pg_moreio || nfs_reqs_to_commit(&cinfo))) |
|
desc->pg_ioflags &= ~FLUSH_COND_STABLE; |
|
|
|
/* Set up the argument struct */ |
|
nfs_pgio_rpcsetup(hdr, mirror->pg_count, desc->pg_ioflags, &cinfo); |
|
desc->pg_rpc_callops = &nfs_pgio_common_ops; |
|
return 0; |
|
} |
|
EXPORT_SYMBOL_GPL(nfs_generic_pgio); |
|
|
|
static int nfs_generic_pg_pgios(struct nfs_pageio_descriptor *desc) |
|
{ |
|
struct nfs_pgio_header *hdr; |
|
int ret; |
|
|
|
hdr = nfs_pgio_header_alloc(desc->pg_rw_ops); |
|
if (!hdr) { |
|
desc->pg_error = -ENOMEM; |
|
return desc->pg_error; |
|
} |
|
nfs_pgheader_init(desc, hdr, nfs_pgio_header_free); |
|
ret = nfs_generic_pgio(desc, hdr); |
|
if (ret == 0) |
|
ret = nfs_initiate_pgio(NFS_CLIENT(hdr->inode), |
|
hdr, |
|
hdr->cred, |
|
NFS_PROTO(hdr->inode), |
|
desc->pg_rpc_callops, |
|
desc->pg_ioflags, |
|
RPC_TASK_CRED_NOREF); |
|
return ret; |
|
} |
|
|
|
static struct nfs_pgio_mirror * |
|
nfs_pageio_alloc_mirrors(struct nfs_pageio_descriptor *desc, |
|
unsigned int mirror_count) |
|
{ |
|
struct nfs_pgio_mirror *ret; |
|
unsigned int i; |
|
|
|
kfree(desc->pg_mirrors_dynamic); |
|
desc->pg_mirrors_dynamic = NULL; |
|
if (mirror_count == 1) |
|
return desc->pg_mirrors_static; |
|
ret = kmalloc_array(mirror_count, sizeof(*ret), GFP_KERNEL); |
|
if (ret != NULL) { |
|
for (i = 0; i < mirror_count; i++) |
|
nfs_pageio_mirror_init(&ret[i], desc->pg_bsize); |
|
desc->pg_mirrors_dynamic = ret; |
|
} |
|
return ret; |
|
} |
|
|
|
/* |
|
* nfs_pageio_setup_mirroring - determine if mirroring is to be used |
|
* by calling the pg_get_mirror_count op |
|
*/ |
|
static void nfs_pageio_setup_mirroring(struct nfs_pageio_descriptor *pgio, |
|
struct nfs_page *req) |
|
{ |
|
unsigned int mirror_count = 1; |
|
|
|
if (pgio->pg_ops->pg_get_mirror_count) |
|
mirror_count = pgio->pg_ops->pg_get_mirror_count(pgio, req); |
|
if (mirror_count == pgio->pg_mirror_count || pgio->pg_error < 0) |
|
return; |
|
|
|
if (!mirror_count || mirror_count > NFS_PAGEIO_DESCRIPTOR_MIRROR_MAX) { |
|
pgio->pg_error = -EINVAL; |
|
return; |
|
} |
|
|
|
pgio->pg_mirrors = nfs_pageio_alloc_mirrors(pgio, mirror_count); |
|
if (pgio->pg_mirrors == NULL) { |
|
pgio->pg_error = -ENOMEM; |
|
pgio->pg_mirrors = pgio->pg_mirrors_static; |
|
mirror_count = 1; |
|
} |
|
pgio->pg_mirror_count = mirror_count; |
|
} |
|
|
|
static void nfs_pageio_cleanup_mirroring(struct nfs_pageio_descriptor *pgio) |
|
{ |
|
pgio->pg_mirror_count = 1; |
|
pgio->pg_mirror_idx = 0; |
|
pgio->pg_mirrors = pgio->pg_mirrors_static; |
|
kfree(pgio->pg_mirrors_dynamic); |
|
pgio->pg_mirrors_dynamic = NULL; |
|
} |
|
|
|
static bool nfs_match_lock_context(const struct nfs_lock_context *l1, |
|
const struct nfs_lock_context *l2) |
|
{ |
|
return l1->lockowner == l2->lockowner; |
|
} |
|
|
|
/** |
|
* nfs_coalesce_size - test two requests for compatibility |
|
* @prev: pointer to nfs_page |
|
* @req: pointer to nfs_page |
|
* @pgio: pointer to nfs_pagio_descriptor |
|
* |
|
* The nfs_page structures 'prev' and 'req' are compared to ensure that the |
|
* page data area they describe is contiguous, and that their RPC |
|
* credentials, NFSv4 open state, and lockowners are the same. |
|
* |
|
* Returns size of the request that can be coalesced |
|
*/ |
|
static unsigned int nfs_coalesce_size(struct nfs_page *prev, |
|
struct nfs_page *req, |
|
struct nfs_pageio_descriptor *pgio) |
|
{ |
|
struct file_lock_context *flctx; |
|
|
|
if (prev) { |
|
if (!nfs_match_open_context(nfs_req_openctx(req), nfs_req_openctx(prev))) |
|
return 0; |
|
flctx = d_inode(nfs_req_openctx(req)->dentry)->i_flctx; |
|
if (flctx != NULL && |
|
!(list_empty_careful(&flctx->flc_posix) && |
|
list_empty_careful(&flctx->flc_flock)) && |
|
!nfs_match_lock_context(req->wb_lock_context, |
|
prev->wb_lock_context)) |
|
return 0; |
|
if (req_offset(req) != req_offset(prev) + prev->wb_bytes) |
|
return 0; |
|
if (req->wb_page == prev->wb_page) { |
|
if (req->wb_pgbase != prev->wb_pgbase + prev->wb_bytes) |
|
return 0; |
|
} else { |
|
if (req->wb_pgbase != 0 || |
|
prev->wb_pgbase + prev->wb_bytes != PAGE_SIZE) |
|
return 0; |
|
} |
|
} |
|
return pgio->pg_ops->pg_test(pgio, prev, req); |
|
} |
|
|
|
/** |
|
* nfs_pageio_do_add_request - Attempt to coalesce a request into a page list. |
|
* @desc: destination io descriptor |
|
* @req: request |
|
* |
|
* If the request 'req' was successfully coalesced into the existing list |
|
* of pages 'desc', it returns the size of req. |
|
*/ |
|
static unsigned int |
|
nfs_pageio_do_add_request(struct nfs_pageio_descriptor *desc, |
|
struct nfs_page *req) |
|
{ |
|
struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc); |
|
struct nfs_page *prev = NULL; |
|
unsigned int size; |
|
|
|
if (list_empty(&mirror->pg_list)) { |
|
if (desc->pg_ops->pg_init) |
|
desc->pg_ops->pg_init(desc, req); |
|
if (desc->pg_error < 0) |
|
return 0; |
|
mirror->pg_base = req->wb_pgbase; |
|
mirror->pg_count = 0; |
|
mirror->pg_recoalesce = 0; |
|
} else |
|
prev = nfs_list_entry(mirror->pg_list.prev); |
|
|
|
if (desc->pg_maxretrans && req->wb_nio > desc->pg_maxretrans) { |
|
if (NFS_SERVER(desc->pg_inode)->flags & NFS_MOUNT_SOFTERR) |
|
desc->pg_error = -ETIMEDOUT; |
|
else |
|
desc->pg_error = -EIO; |
|
return 0; |
|
} |
|
|
|
size = nfs_coalesce_size(prev, req, desc); |
|
if (size < req->wb_bytes) |
|
return size; |
|
nfs_list_move_request(req, &mirror->pg_list); |
|
mirror->pg_count += req->wb_bytes; |
|
return req->wb_bytes; |
|
} |
|
|
|
/* |
|
* Helper for nfs_pageio_add_request and nfs_pageio_complete |
|
*/ |
|
static void nfs_pageio_doio(struct nfs_pageio_descriptor *desc) |
|
{ |
|
struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc); |
|
|
|
if (!list_empty(&mirror->pg_list)) { |
|
int error = desc->pg_ops->pg_doio(desc); |
|
if (error < 0) |
|
desc->pg_error = error; |
|
if (list_empty(&mirror->pg_list)) { |
|
mirror->pg_bytes_written += mirror->pg_count; |
|
mirror->pg_count = 0; |
|
mirror->pg_base = 0; |
|
mirror->pg_recoalesce = 0; |
|
} |
|
} |
|
} |
|
|
|
static void |
|
nfs_pageio_cleanup_request(struct nfs_pageio_descriptor *desc, |
|
struct nfs_page *req) |
|
{ |
|
LIST_HEAD(head); |
|
|
|
nfs_list_move_request(req, &head); |
|
desc->pg_completion_ops->error_cleanup(&head, desc->pg_error); |
|
} |
|
|
|
/** |
|
* nfs_pageio_add_request - Attempt to coalesce a request into a page list. |
|
* @desc: destination io descriptor |
|
* @req: request |
|
* |
|
* This may split a request into subrequests which are all part of the |
|
* same page group. If so, it will submit @req as the last one, to ensure |
|
* the pointer to @req is still valid in case of failure. |
|
* |
|
* Returns true if the request 'req' was successfully coalesced into the |
|
* existing list of pages 'desc'. |
|
*/ |
|
static int __nfs_pageio_add_request(struct nfs_pageio_descriptor *desc, |
|
struct nfs_page *req) |
|
{ |
|
struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc); |
|
struct nfs_page *subreq; |
|
unsigned int size, subreq_size; |
|
|
|
nfs_page_group_lock(req); |
|
|
|
subreq = req; |
|
subreq_size = subreq->wb_bytes; |
|
for(;;) { |
|
size = nfs_pageio_do_add_request(desc, subreq); |
|
if (size == subreq_size) { |
|
/* We successfully submitted a request */ |
|
if (subreq == req) |
|
break; |
|
req->wb_pgbase += size; |
|
req->wb_bytes -= size; |
|
req->wb_offset += size; |
|
subreq_size = req->wb_bytes; |
|
subreq = req; |
|
continue; |
|
} |
|
if (WARN_ON_ONCE(subreq != req)) { |
|
nfs_page_group_unlock(req); |
|
nfs_pageio_cleanup_request(desc, subreq); |
|
subreq = req; |
|
subreq_size = req->wb_bytes; |
|
nfs_page_group_lock(req); |
|
} |
|
if (!size) { |
|
/* Can't coalesce any more, so do I/O */ |
|
nfs_page_group_unlock(req); |
|
desc->pg_moreio = 1; |
|
nfs_pageio_doio(desc); |
|
if (desc->pg_error < 0 || mirror->pg_recoalesce) |
|
return 0; |
|
/* retry add_request for this subreq */ |
|
nfs_page_group_lock(req); |
|
continue; |
|
} |
|
subreq = nfs_create_subreq(req, req->wb_pgbase, |
|
req->wb_offset, size); |
|
if (IS_ERR(subreq)) |
|
goto err_ptr; |
|
subreq_size = size; |
|
} |
|
|
|
nfs_page_group_unlock(req); |
|
return 1; |
|
err_ptr: |
|
desc->pg_error = PTR_ERR(subreq); |
|
nfs_page_group_unlock(req); |
|
return 0; |
|
} |
|
|
|
static int nfs_do_recoalesce(struct nfs_pageio_descriptor *desc) |
|
{ |
|
struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc); |
|
LIST_HEAD(head); |
|
|
|
do { |
|
list_splice_init(&mirror->pg_list, &head); |
|
mirror->pg_count = 0; |
|
mirror->pg_base = 0; |
|
mirror->pg_recoalesce = 0; |
|
|
|
while (!list_empty(&head)) { |
|
struct nfs_page *req; |
|
|
|
req = list_first_entry(&head, struct nfs_page, wb_list); |
|
if (__nfs_pageio_add_request(desc, req)) |
|
continue; |
|
if (desc->pg_error < 0) { |
|
list_splice_tail(&head, &mirror->pg_list); |
|
mirror->pg_recoalesce = 1; |
|
return 0; |
|
} |
|
break; |
|
} |
|
} while (mirror->pg_recoalesce); |
|
return 1; |
|
} |
|
|
|
static int nfs_pageio_add_request_mirror(struct nfs_pageio_descriptor *desc, |
|
struct nfs_page *req) |
|
{ |
|
int ret; |
|
|
|
do { |
|
ret = __nfs_pageio_add_request(desc, req); |
|
if (ret) |
|
break; |
|
if (desc->pg_error < 0) |
|
break; |
|
ret = nfs_do_recoalesce(desc); |
|
} while (ret); |
|
|
|
return ret; |
|
} |
|
|
|
static void nfs_pageio_error_cleanup(struct nfs_pageio_descriptor *desc) |
|
{ |
|
u32 midx; |
|
struct nfs_pgio_mirror *mirror; |
|
|
|
if (!desc->pg_error) |
|
return; |
|
|
|
for (midx = 0; midx < desc->pg_mirror_count; midx++) { |
|
mirror = nfs_pgio_get_mirror(desc, midx); |
|
desc->pg_completion_ops->error_cleanup(&mirror->pg_list, |
|
desc->pg_error); |
|
} |
|
} |
|
|
|
int nfs_pageio_add_request(struct nfs_pageio_descriptor *desc, |
|
struct nfs_page *req) |
|
{ |
|
u32 midx; |
|
unsigned int pgbase, offset, bytes; |
|
struct nfs_page *dupreq; |
|
|
|
pgbase = req->wb_pgbase; |
|
offset = req->wb_offset; |
|
bytes = req->wb_bytes; |
|
|
|
nfs_pageio_setup_mirroring(desc, req); |
|
if (desc->pg_error < 0) |
|
goto out_failed; |
|
|
|
/* Create the mirror instances first, and fire them off */ |
|
for (midx = 1; midx < desc->pg_mirror_count; midx++) { |
|
nfs_page_group_lock(req); |
|
|
|
dupreq = nfs_create_subreq(req, |
|
pgbase, offset, bytes); |
|
|
|
nfs_page_group_unlock(req); |
|
if (IS_ERR(dupreq)) { |
|
desc->pg_error = PTR_ERR(dupreq); |
|
goto out_failed; |
|
} |
|
|
|
nfs_pgio_set_current_mirror(desc, midx); |
|
if (!nfs_pageio_add_request_mirror(desc, dupreq)) |
|
goto out_cleanup_subreq; |
|
} |
|
|
|
nfs_pgio_set_current_mirror(desc, 0); |
|
if (!nfs_pageio_add_request_mirror(desc, req)) |
|
goto out_failed; |
|
|
|
return 1; |
|
|
|
out_cleanup_subreq: |
|
nfs_pageio_cleanup_request(desc, dupreq); |
|
out_failed: |
|
nfs_pageio_error_cleanup(desc); |
|
return 0; |
|
} |
|
|
|
/* |
|
* nfs_pageio_complete_mirror - Complete I/O on the current mirror of an |
|
* nfs_pageio_descriptor |
|
* @desc: pointer to io descriptor |
|
* @mirror_idx: pointer to mirror index |
|
*/ |
|
static void nfs_pageio_complete_mirror(struct nfs_pageio_descriptor *desc, |
|
u32 mirror_idx) |
|
{ |
|
struct nfs_pgio_mirror *mirror; |
|
u32 restore_idx; |
|
|
|
restore_idx = nfs_pgio_set_current_mirror(desc, mirror_idx); |
|
mirror = nfs_pgio_current_mirror(desc); |
|
|
|
for (;;) { |
|
nfs_pageio_doio(desc); |
|
if (desc->pg_error < 0 || !mirror->pg_recoalesce) |
|
break; |
|
if (!nfs_do_recoalesce(desc)) |
|
break; |
|
} |
|
nfs_pgio_set_current_mirror(desc, restore_idx); |
|
} |
|
|
|
/* |
|
* nfs_pageio_resend - Transfer requests to new descriptor and resend |
|
* @hdr - the pgio header to move request from |
|
* @desc - the pageio descriptor to add requests to |
|
* |
|
* Try to move each request (nfs_page) from @hdr to @desc then attempt |
|
* to send them. |
|
* |
|
* Returns 0 on success and < 0 on error. |
|
*/ |
|
int nfs_pageio_resend(struct nfs_pageio_descriptor *desc, |
|
struct nfs_pgio_header *hdr) |
|
{ |
|
LIST_HEAD(pages); |
|
|
|
desc->pg_io_completion = hdr->io_completion; |
|
desc->pg_dreq = hdr->dreq; |
|
list_splice_init(&hdr->pages, &pages); |
|
while (!list_empty(&pages)) { |
|
struct nfs_page *req = nfs_list_entry(pages.next); |
|
|
|
if (!nfs_pageio_add_request(desc, req)) |
|
break; |
|
} |
|
nfs_pageio_complete(desc); |
|
if (!list_empty(&pages)) { |
|
int err = desc->pg_error < 0 ? desc->pg_error : -EIO; |
|
hdr->completion_ops->error_cleanup(&pages, err); |
|
nfs_set_pgio_error(hdr, err, hdr->io_start); |
|
return err; |
|
} |
|
return 0; |
|
} |
|
EXPORT_SYMBOL_GPL(nfs_pageio_resend); |
|
|
|
/** |
|
* nfs_pageio_complete - Complete I/O then cleanup an nfs_pageio_descriptor |
|
* @desc: pointer to io descriptor |
|
*/ |
|
void nfs_pageio_complete(struct nfs_pageio_descriptor *desc) |
|
{ |
|
u32 midx; |
|
|
|
for (midx = 0; midx < desc->pg_mirror_count; midx++) |
|
nfs_pageio_complete_mirror(desc, midx); |
|
|
|
if (desc->pg_error < 0) |
|
nfs_pageio_error_cleanup(desc); |
|
if (desc->pg_ops->pg_cleanup) |
|
desc->pg_ops->pg_cleanup(desc); |
|
nfs_pageio_cleanup_mirroring(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) |
|
{ |
|
struct nfs_pgio_mirror *mirror; |
|
struct nfs_page *prev; |
|
u32 midx; |
|
|
|
for (midx = 0; midx < desc->pg_mirror_count; midx++) { |
|
mirror = nfs_pgio_get_mirror(desc, midx); |
|
if (!list_empty(&mirror->pg_list)) { |
|
prev = nfs_list_entry(mirror->pg_list.prev); |
|
if (index != prev->wb_index + 1) { |
|
nfs_pageio_complete(desc); |
|
break; |
|
} |
|
} |
|
} |
|
} |
|
|
|
/* |
|
* nfs_pageio_stop_mirroring - stop using mirroring (set mirror count to 1) |
|
*/ |
|
void nfs_pageio_stop_mirroring(struct nfs_pageio_descriptor *pgio) |
|
{ |
|
nfs_pageio_complete(pgio); |
|
} |
|
|
|
int __init nfs_init_nfspagecache(void) |
|
{ |
|
nfs_page_cachep = kmem_cache_create("nfs_page", |
|
sizeof(struct nfs_page), |
|
0, SLAB_HWCACHE_ALIGN, |
|
NULL); |
|
if (nfs_page_cachep == NULL) |
|
return -ENOMEM; |
|
|
|
return 0; |
|
} |
|
|
|
void nfs_destroy_nfspagecache(void) |
|
{ |
|
kmem_cache_destroy(nfs_page_cachep); |
|
} |
|
|
|
static const struct rpc_call_ops nfs_pgio_common_ops = { |
|
.rpc_call_prepare = nfs_pgio_prepare, |
|
.rpc_call_done = nfs_pgio_result, |
|
.rpc_release = nfs_pgio_release, |
|
}; |
|
|
|
const struct nfs_pageio_ops nfs_pgio_rw_ops = { |
|
.pg_test = nfs_generic_pg_test, |
|
.pg_doio = nfs_generic_pg_pgios, |
|
};
|
|
|