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2193 lines
57 KiB
2193 lines
57 KiB
// SPDX-License-Identifier: GPL-2.0-only |
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/* |
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* linux/fs/nfs/write.c |
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* |
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* Write file data over NFS. |
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* |
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* Copyright (C) 1996, 1997, Olaf Kirch <[email protected]> |
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*/ |
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|
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#include <linux/types.h> |
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#include <linux/slab.h> |
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#include <linux/mm.h> |
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#include <linux/pagemap.h> |
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#include <linux/file.h> |
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#include <linux/writeback.h> |
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#include <linux/swap.h> |
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#include <linux/migrate.h> |
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|
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#include <linux/sunrpc/clnt.h> |
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#include <linux/nfs_fs.h> |
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#include <linux/nfs_mount.h> |
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#include <linux/nfs_page.h> |
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#include <linux/backing-dev.h> |
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#include <linux/export.h> |
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#include <linux/freezer.h> |
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#include <linux/wait.h> |
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#include <linux/iversion.h> |
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|
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#include <linux/uaccess.h> |
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#include <linux/sched/mm.h> |
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|
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#include "delegation.h" |
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#include "internal.h" |
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#include "iostat.h" |
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#include "nfs4_fs.h" |
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#include "fscache.h" |
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#include "pnfs.h" |
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|
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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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#define MIN_POOL_WRITE (32) |
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#define MIN_POOL_COMMIT (4) |
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|
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struct nfs_io_completion { |
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void (*complete)(void *data); |
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void *data; |
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struct kref refcount; |
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}; |
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|
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/* |
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* Local function declarations |
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*/ |
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static void nfs_redirty_request(struct nfs_page *req); |
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static const struct rpc_call_ops nfs_commit_ops; |
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static const struct nfs_pgio_completion_ops nfs_async_write_completion_ops; |
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static const struct nfs_commit_completion_ops nfs_commit_completion_ops; |
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static const struct nfs_rw_ops nfs_rw_write_ops; |
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static void nfs_inode_remove_request(struct nfs_page *req); |
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static void nfs_clear_request_commit(struct nfs_page *req); |
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static void nfs_init_cinfo_from_inode(struct nfs_commit_info *cinfo, |
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struct inode *inode); |
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static struct nfs_page * |
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nfs_page_search_commits_for_head_request_locked(struct nfs_inode *nfsi, |
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struct page *page); |
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|
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static struct kmem_cache *nfs_wdata_cachep; |
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static mempool_t *nfs_wdata_mempool; |
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static struct kmem_cache *nfs_cdata_cachep; |
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static mempool_t *nfs_commit_mempool; |
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|
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struct nfs_commit_data *nfs_commitdata_alloc(bool never_fail) |
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{ |
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struct nfs_commit_data *p; |
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|
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if (never_fail) |
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p = mempool_alloc(nfs_commit_mempool, GFP_NOIO); |
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else { |
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/* It is OK to do some reclaim, not no safe to wait |
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* for anything to be returned to the pool. |
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* mempool_alloc() cannot handle that particular combination, |
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* so we need two separate attempts. |
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*/ |
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p = mempool_alloc(nfs_commit_mempool, GFP_NOWAIT); |
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if (!p) |
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p = kmem_cache_alloc(nfs_cdata_cachep, GFP_NOIO | |
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__GFP_NOWARN | __GFP_NORETRY); |
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if (!p) |
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return NULL; |
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} |
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|
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memset(p, 0, sizeof(*p)); |
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INIT_LIST_HEAD(&p->pages); |
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return p; |
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} |
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EXPORT_SYMBOL_GPL(nfs_commitdata_alloc); |
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|
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void nfs_commit_free(struct nfs_commit_data *p) |
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{ |
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mempool_free(p, nfs_commit_mempool); |
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} |
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EXPORT_SYMBOL_GPL(nfs_commit_free); |
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|
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static struct nfs_pgio_header *nfs_writehdr_alloc(void) |
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{ |
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struct nfs_pgio_header *p = mempool_alloc(nfs_wdata_mempool, GFP_KERNEL); |
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|
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memset(p, 0, sizeof(*p)); |
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p->rw_mode = FMODE_WRITE; |
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return p; |
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} |
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|
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static void nfs_writehdr_free(struct nfs_pgio_header *hdr) |
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{ |
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mempool_free(hdr, nfs_wdata_mempool); |
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} |
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|
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static struct nfs_io_completion *nfs_io_completion_alloc(gfp_t gfp_flags) |
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{ |
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return kmalloc(sizeof(struct nfs_io_completion), gfp_flags); |
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} |
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|
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static void nfs_io_completion_init(struct nfs_io_completion *ioc, |
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void (*complete)(void *), void *data) |
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{ |
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ioc->complete = complete; |
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ioc->data = data; |
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kref_init(&ioc->refcount); |
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} |
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|
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static void nfs_io_completion_release(struct kref *kref) |
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{ |
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struct nfs_io_completion *ioc = container_of(kref, |
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struct nfs_io_completion, refcount); |
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ioc->complete(ioc->data); |
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kfree(ioc); |
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} |
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|
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static void nfs_io_completion_get(struct nfs_io_completion *ioc) |
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{ |
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if (ioc != NULL) |
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kref_get(&ioc->refcount); |
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} |
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|
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static void nfs_io_completion_put(struct nfs_io_completion *ioc) |
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{ |
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if (ioc != NULL) |
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kref_put(&ioc->refcount, nfs_io_completion_release); |
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} |
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|
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static void |
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nfs_page_set_inode_ref(struct nfs_page *req, struct inode *inode) |
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{ |
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if (!test_and_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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static int |
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nfs_cancel_remove_inode(struct nfs_page *req, struct inode *inode) |
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{ |
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int ret; |
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|
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if (!test_bit(PG_REMOVE, &req->wb_flags)) |
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return 0; |
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ret = nfs_page_group_lock(req); |
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if (ret) |
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return ret; |
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if (test_and_clear_bit(PG_REMOVE, &req->wb_flags)) |
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nfs_page_set_inode_ref(req, inode); |
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nfs_page_group_unlock(req); |
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return 0; |
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} |
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|
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static struct nfs_page * |
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nfs_page_private_request(struct page *page) |
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{ |
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if (!PagePrivate(page)) |
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return NULL; |
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return (struct nfs_page *)page_private(page); |
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} |
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|
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/* |
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* nfs_page_find_head_request_locked - find head request associated with @page |
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* |
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* must be called while holding the inode lock. |
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* |
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* returns matching head request with reference held, or NULL if not found. |
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*/ |
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static struct nfs_page * |
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nfs_page_find_private_request(struct page *page) |
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{ |
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struct address_space *mapping = page_file_mapping(page); |
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struct nfs_page *req; |
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|
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if (!PagePrivate(page)) |
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return NULL; |
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spin_lock(&mapping->private_lock); |
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req = nfs_page_private_request(page); |
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if (req) { |
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WARN_ON_ONCE(req->wb_head != req); |
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kref_get(&req->wb_kref); |
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} |
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spin_unlock(&mapping->private_lock); |
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return req; |
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} |
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|
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static struct nfs_page * |
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nfs_page_find_swap_request(struct page *page) |
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{ |
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struct inode *inode = page_file_mapping(page)->host; |
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struct nfs_inode *nfsi = NFS_I(inode); |
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struct nfs_page *req = NULL; |
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if (!PageSwapCache(page)) |
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return NULL; |
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mutex_lock(&nfsi->commit_mutex); |
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if (PageSwapCache(page)) { |
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req = nfs_page_search_commits_for_head_request_locked(nfsi, |
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page); |
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if (req) { |
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WARN_ON_ONCE(req->wb_head != req); |
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kref_get(&req->wb_kref); |
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} |
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} |
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mutex_unlock(&nfsi->commit_mutex); |
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return req; |
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} |
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|
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/* |
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* nfs_page_find_head_request - find head request associated with @page |
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* |
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* returns matching head request with reference held, or NULL if not found. |
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*/ |
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static struct nfs_page *nfs_page_find_head_request(struct page *page) |
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{ |
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struct nfs_page *req; |
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|
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req = nfs_page_find_private_request(page); |
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if (!req) |
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req = nfs_page_find_swap_request(page); |
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return req; |
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} |
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|
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static struct nfs_page *nfs_find_and_lock_page_request(struct page *page) |
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{ |
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struct inode *inode = page_file_mapping(page)->host; |
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struct nfs_page *req, *head; |
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int ret; |
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|
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for (;;) { |
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req = nfs_page_find_head_request(page); |
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if (!req) |
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return req; |
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head = nfs_page_group_lock_head(req); |
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if (head != req) |
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nfs_release_request(req); |
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if (IS_ERR(head)) |
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return head; |
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ret = nfs_cancel_remove_inode(head, inode); |
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if (ret < 0) { |
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nfs_unlock_and_release_request(head); |
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return ERR_PTR(ret); |
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} |
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/* Ensure that nobody removed the request before we locked it */ |
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if (head == nfs_page_private_request(page)) |
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break; |
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if (PageSwapCache(page)) |
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break; |
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nfs_unlock_and_release_request(head); |
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} |
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return head; |
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} |
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|
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/* Adjust the file length if we're writing beyond the end */ |
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static void nfs_grow_file(struct page *page, unsigned int offset, unsigned int count) |
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{ |
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struct inode *inode = page_file_mapping(page)->host; |
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loff_t end, i_size; |
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pgoff_t end_index; |
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|
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spin_lock(&inode->i_lock); |
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i_size = i_size_read(inode); |
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end_index = (i_size - 1) >> PAGE_SHIFT; |
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if (i_size > 0 && page_index(page) < end_index) |
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goto out; |
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end = page_file_offset(page) + ((loff_t)offset+count); |
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if (i_size >= end) |
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goto out; |
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i_size_write(inode, end); |
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NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_SIZE; |
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nfs_inc_stats(inode, NFSIOS_EXTENDWRITE); |
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out: |
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spin_unlock(&inode->i_lock); |
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} |
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/* A writeback failed: mark the page as bad, and invalidate the page cache */ |
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static void nfs_set_pageerror(struct address_space *mapping) |
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{ |
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struct inode *inode = mapping->host; |
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nfs_zap_mapping(mapping->host, mapping); |
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/* Force file size revalidation */ |
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spin_lock(&inode->i_lock); |
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NFS_I(inode)->cache_validity |= NFS_INO_REVAL_FORCED | |
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NFS_INO_REVAL_PAGECACHE | |
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NFS_INO_INVALID_SIZE; |
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spin_unlock(&inode->i_lock); |
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} |
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static void nfs_mapping_set_error(struct page *page, int error) |
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{ |
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struct address_space *mapping = page_file_mapping(page); |
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SetPageError(page); |
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mapping_set_error(mapping, error); |
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nfs_set_pageerror(mapping); |
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} |
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|
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/* |
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* nfs_page_group_search_locked |
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* @head - head request of page group |
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* @page_offset - offset into page |
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* |
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* Search page group with head @head to find a request that contains the |
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* page offset @page_offset. |
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* |
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* Returns a pointer to the first matching nfs request, or NULL if no |
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* match is found. |
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* |
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* Must be called with the page group lock held |
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*/ |
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static struct nfs_page * |
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nfs_page_group_search_locked(struct nfs_page *head, unsigned int page_offset) |
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{ |
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struct nfs_page *req; |
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req = head; |
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do { |
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if (page_offset >= req->wb_pgbase && |
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page_offset < (req->wb_pgbase + req->wb_bytes)) |
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return req; |
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|
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req = req->wb_this_page; |
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} while (req != head); |
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return NULL; |
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} |
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|
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/* |
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* nfs_page_group_covers_page |
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* @head - head request of page group |
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* |
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* Return true if the page group with head @head covers the whole page, |
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* returns false otherwise |
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*/ |
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static bool nfs_page_group_covers_page(struct nfs_page *req) |
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{ |
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struct nfs_page *tmp; |
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unsigned int pos = 0; |
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unsigned int len = nfs_page_length(req->wb_page); |
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|
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nfs_page_group_lock(req); |
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|
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for (;;) { |
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tmp = nfs_page_group_search_locked(req->wb_head, pos); |
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if (!tmp) |
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break; |
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pos = tmp->wb_pgbase + tmp->wb_bytes; |
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} |
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|
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nfs_page_group_unlock(req); |
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return pos >= len; |
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} |
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|
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/* We can set the PG_uptodate flag if we see that a write request |
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* covers the full page. |
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*/ |
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static void nfs_mark_uptodate(struct nfs_page *req) |
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{ |
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if (PageUptodate(req->wb_page)) |
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return; |
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if (!nfs_page_group_covers_page(req)) |
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return; |
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SetPageUptodate(req->wb_page); |
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} |
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|
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static int wb_priority(struct writeback_control *wbc) |
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{ |
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int ret = 0; |
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|
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if (wbc->sync_mode == WB_SYNC_ALL) |
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ret = FLUSH_COND_STABLE; |
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return ret; |
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} |
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|
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/* |
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* NFS congestion control |
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*/ |
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|
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int nfs_congestion_kb; |
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|
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#define NFS_CONGESTION_ON_THRESH (nfs_congestion_kb >> (PAGE_SHIFT-10)) |
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#define NFS_CONGESTION_OFF_THRESH \ |
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(NFS_CONGESTION_ON_THRESH - (NFS_CONGESTION_ON_THRESH >> 2)) |
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|
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static void nfs_set_page_writeback(struct page *page) |
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{ |
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struct inode *inode = page_file_mapping(page)->host; |
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struct nfs_server *nfss = NFS_SERVER(inode); |
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int ret = test_set_page_writeback(page); |
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|
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WARN_ON_ONCE(ret != 0); |
|
|
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if (atomic_long_inc_return(&nfss->writeback) > |
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NFS_CONGESTION_ON_THRESH) |
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set_bdi_congested(inode_to_bdi(inode), BLK_RW_ASYNC); |
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} |
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|
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static void nfs_end_page_writeback(struct nfs_page *req) |
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{ |
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struct inode *inode = page_file_mapping(req->wb_page)->host; |
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struct nfs_server *nfss = NFS_SERVER(inode); |
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bool is_done; |
|
|
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is_done = nfs_page_group_sync_on_bit(req, PG_WB_END); |
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nfs_unlock_request(req); |
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if (!is_done) |
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return; |
|
|
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end_page_writeback(req->wb_page); |
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if (atomic_long_dec_return(&nfss->writeback) < NFS_CONGESTION_OFF_THRESH) |
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clear_bdi_congested(inode_to_bdi(inode), BLK_RW_ASYNC); |
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} |
|
|
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/* |
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* nfs_destroy_unlinked_subrequests - destroy recently unlinked subrequests |
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* |
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* @destroy_list - request list (using wb_this_page) terminated by @old_head |
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* @old_head - the old head of the list |
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* |
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* All subrequests must be locked and removed from all lists, so at this point |
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* they are only "active" in this function, and possibly in nfs_wait_on_request |
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* with a reference held by some other context. |
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*/ |
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static void |
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nfs_destroy_unlinked_subrequests(struct nfs_page *destroy_list, |
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struct nfs_page *old_head, |
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struct inode *inode) |
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{ |
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while (destroy_list) { |
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struct nfs_page *subreq = destroy_list; |
|
|
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destroy_list = (subreq->wb_this_page == old_head) ? |
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NULL : subreq->wb_this_page; |
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|
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/* Note: lock subreq in order to change subreq->wb_head */ |
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nfs_page_set_headlock(subreq); |
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WARN_ON_ONCE(old_head != subreq->wb_head); |
|
|
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/* make sure old group is not used */ |
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subreq->wb_this_page = subreq; |
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subreq->wb_head = subreq; |
|
|
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clear_bit(PG_REMOVE, &subreq->wb_flags); |
|
|
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/* Note: races with nfs_page_group_destroy() */ |
|
if (!kref_read(&subreq->wb_kref)) { |
|
/* Check if we raced with nfs_page_group_destroy() */ |
|
if (test_and_clear_bit(PG_TEARDOWN, &subreq->wb_flags)) { |
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nfs_page_clear_headlock(subreq); |
|
nfs_free_request(subreq); |
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} else |
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nfs_page_clear_headlock(subreq); |
|
continue; |
|
} |
|
nfs_page_clear_headlock(subreq); |
|
|
|
nfs_release_request(old_head); |
|
|
|
if (test_and_clear_bit(PG_INODE_REF, &subreq->wb_flags)) { |
|
nfs_release_request(subreq); |
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atomic_long_dec(&NFS_I(inode)->nrequests); |
|
} |
|
|
|
/* subreq is now totally disconnected from page group or any |
|
* write / commit lists. last chance to wake any waiters */ |
|
nfs_unlock_and_release_request(subreq); |
|
} |
|
} |
|
|
|
/* |
|
* nfs_join_page_group - destroy subrequests of the head req |
|
* @head: the page used to lookup the "page group" of nfs_page structures |
|
* @inode: Inode to which the request belongs. |
|
* |
|
* This function joins all sub requests to the head request by first |
|
* locking all requests in the group, cancelling any pending operations |
|
* and finally updating the head request to cover the whole range covered by |
|
* the (former) group. All subrequests are removed from any write or commit |
|
* lists, unlinked from the group and destroyed. |
|
*/ |
|
void |
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nfs_join_page_group(struct nfs_page *head, struct inode *inode) |
|
{ |
|
struct nfs_page *subreq; |
|
struct nfs_page *destroy_list = NULL; |
|
unsigned int pgbase, off, bytes; |
|
|
|
pgbase = head->wb_pgbase; |
|
bytes = head->wb_bytes; |
|
off = head->wb_offset; |
|
for (subreq = head->wb_this_page; subreq != head; |
|
subreq = subreq->wb_this_page) { |
|
/* Subrequests should always form a contiguous range */ |
|
if (pgbase > subreq->wb_pgbase) { |
|
off -= pgbase - subreq->wb_pgbase; |
|
bytes += pgbase - subreq->wb_pgbase; |
|
pgbase = subreq->wb_pgbase; |
|
} |
|
bytes = max(subreq->wb_pgbase + subreq->wb_bytes |
|
- pgbase, bytes); |
|
} |
|
|
|
/* Set the head request's range to cover the former page group */ |
|
head->wb_pgbase = pgbase; |
|
head->wb_bytes = bytes; |
|
head->wb_offset = off; |
|
|
|
/* Now that all requests are locked, make sure they aren't on any list. |
|
* Commit list removal accounting is done after locks are dropped */ |
|
subreq = head; |
|
do { |
|
nfs_clear_request_commit(subreq); |
|
subreq = subreq->wb_this_page; |
|
} while (subreq != head); |
|
|
|
/* unlink subrequests from head, destroy them later */ |
|
if (head->wb_this_page != head) { |
|
/* destroy list will be terminated by head */ |
|
destroy_list = head->wb_this_page; |
|
head->wb_this_page = head; |
|
} |
|
|
|
nfs_destroy_unlinked_subrequests(destroy_list, head, inode); |
|
} |
|
|
|
/* |
|
* nfs_lock_and_join_requests - join all subreqs to the head req |
|
* @page: the page used to lookup the "page group" of nfs_page structures |
|
* |
|
* This function joins all sub requests to the head request by first |
|
* locking all requests in the group, cancelling any pending operations |
|
* and finally updating the head request to cover the whole range covered by |
|
* the (former) group. All subrequests are removed from any write or commit |
|
* lists, unlinked from the group and destroyed. |
|
* |
|
* Returns a locked, referenced pointer to the head request - which after |
|
* this call is guaranteed to be the only request associated with the page. |
|
* Returns NULL if no requests are found for @page, or a ERR_PTR if an |
|
* error was encountered. |
|
*/ |
|
static struct nfs_page * |
|
nfs_lock_and_join_requests(struct page *page) |
|
{ |
|
struct inode *inode = page_file_mapping(page)->host; |
|
struct nfs_page *head; |
|
int ret; |
|
|
|
/* |
|
* A reference is taken only on the head request which acts as a |
|
* reference to the whole page group - the group will not be destroyed |
|
* until the head reference is released. |
|
*/ |
|
head = nfs_find_and_lock_page_request(page); |
|
if (IS_ERR_OR_NULL(head)) |
|
return head; |
|
|
|
/* lock each request in the page group */ |
|
ret = nfs_page_group_lock_subrequests(head); |
|
if (ret < 0) { |
|
nfs_unlock_and_release_request(head); |
|
return ERR_PTR(ret); |
|
} |
|
|
|
nfs_join_page_group(head, inode); |
|
|
|
return head; |
|
} |
|
|
|
static void nfs_write_error(struct nfs_page *req, int error) |
|
{ |
|
trace_nfs_write_error(req, error); |
|
nfs_mapping_set_error(req->wb_page, error); |
|
nfs_inode_remove_request(req); |
|
nfs_end_page_writeback(req); |
|
nfs_release_request(req); |
|
} |
|
|
|
/* |
|
* Find an associated nfs write request, and prepare to flush it out |
|
* May return an error if the user signalled nfs_wait_on_request(). |
|
*/ |
|
static int nfs_page_async_flush(struct nfs_pageio_descriptor *pgio, |
|
struct page *page) |
|
{ |
|
struct nfs_page *req; |
|
int ret = 0; |
|
|
|
req = nfs_lock_and_join_requests(page); |
|
if (!req) |
|
goto out; |
|
ret = PTR_ERR(req); |
|
if (IS_ERR(req)) |
|
goto out; |
|
|
|
nfs_set_page_writeback(page); |
|
WARN_ON_ONCE(test_bit(PG_CLEAN, &req->wb_flags)); |
|
|
|
/* If there is a fatal error that covers this write, just exit */ |
|
ret = pgio->pg_error; |
|
if (nfs_error_is_fatal_on_server(ret)) |
|
goto out_launder; |
|
|
|
ret = 0; |
|
if (!nfs_pageio_add_request(pgio, req)) { |
|
ret = pgio->pg_error; |
|
/* |
|
* Remove the problematic req upon fatal errors on the server |
|
*/ |
|
if (nfs_error_is_fatal(ret)) { |
|
if (nfs_error_is_fatal_on_server(ret)) |
|
goto out_launder; |
|
} else |
|
ret = -EAGAIN; |
|
nfs_redirty_request(req); |
|
pgio->pg_error = 0; |
|
} else |
|
nfs_add_stats(page_file_mapping(page)->host, |
|
NFSIOS_WRITEPAGES, 1); |
|
out: |
|
return ret; |
|
out_launder: |
|
nfs_write_error(req, ret); |
|
return 0; |
|
} |
|
|
|
static int nfs_do_writepage(struct page *page, struct writeback_control *wbc, |
|
struct nfs_pageio_descriptor *pgio) |
|
{ |
|
int ret; |
|
|
|
nfs_pageio_cond_complete(pgio, page_index(page)); |
|
ret = nfs_page_async_flush(pgio, page); |
|
if (ret == -EAGAIN) { |
|
redirty_page_for_writepage(wbc, page); |
|
ret = AOP_WRITEPAGE_ACTIVATE; |
|
} |
|
return ret; |
|
} |
|
|
|
/* |
|
* Write an mmapped page to the server. |
|
*/ |
|
static int nfs_writepage_locked(struct page *page, |
|
struct writeback_control *wbc) |
|
{ |
|
struct nfs_pageio_descriptor pgio; |
|
struct inode *inode = page_file_mapping(page)->host; |
|
int err; |
|
|
|
nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGE); |
|
nfs_pageio_init_write(&pgio, inode, 0, |
|
false, &nfs_async_write_completion_ops); |
|
err = nfs_do_writepage(page, wbc, &pgio); |
|
pgio.pg_error = 0; |
|
nfs_pageio_complete(&pgio); |
|
if (err < 0) |
|
return err; |
|
if (nfs_error_is_fatal(pgio.pg_error)) |
|
return pgio.pg_error; |
|
return 0; |
|
} |
|
|
|
int nfs_writepage(struct page *page, struct writeback_control *wbc) |
|
{ |
|
int ret; |
|
|
|
ret = nfs_writepage_locked(page, wbc); |
|
if (ret != AOP_WRITEPAGE_ACTIVATE) |
|
unlock_page(page); |
|
return ret; |
|
} |
|
|
|
static int nfs_writepages_callback(struct page *page, struct writeback_control *wbc, void *data) |
|
{ |
|
int ret; |
|
|
|
ret = nfs_do_writepage(page, wbc, data); |
|
if (ret != AOP_WRITEPAGE_ACTIVATE) |
|
unlock_page(page); |
|
return ret; |
|
} |
|
|
|
static void nfs_io_completion_commit(void *inode) |
|
{ |
|
nfs_commit_inode(inode, 0); |
|
} |
|
|
|
int nfs_writepages(struct address_space *mapping, struct writeback_control *wbc) |
|
{ |
|
struct inode *inode = mapping->host; |
|
struct nfs_pageio_descriptor pgio; |
|
struct nfs_io_completion *ioc; |
|
int err; |
|
|
|
nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGES); |
|
|
|
ioc = nfs_io_completion_alloc(GFP_KERNEL); |
|
if (ioc) |
|
nfs_io_completion_init(ioc, nfs_io_completion_commit, inode); |
|
|
|
nfs_pageio_init_write(&pgio, inode, wb_priority(wbc), false, |
|
&nfs_async_write_completion_ops); |
|
pgio.pg_io_completion = ioc; |
|
err = write_cache_pages(mapping, wbc, nfs_writepages_callback, &pgio); |
|
pgio.pg_error = 0; |
|
nfs_pageio_complete(&pgio); |
|
nfs_io_completion_put(ioc); |
|
|
|
if (err < 0) |
|
goto out_err; |
|
err = pgio.pg_error; |
|
if (nfs_error_is_fatal(err)) |
|
goto out_err; |
|
return 0; |
|
out_err: |
|
return err; |
|
} |
|
|
|
/* |
|
* Insert a write request into an inode |
|
*/ |
|
static void nfs_inode_add_request(struct inode *inode, struct nfs_page *req) |
|
{ |
|
struct address_space *mapping = page_file_mapping(req->wb_page); |
|
struct nfs_inode *nfsi = NFS_I(inode); |
|
|
|
WARN_ON_ONCE(req->wb_this_page != req); |
|
|
|
/* Lock the request! */ |
|
nfs_lock_request(req); |
|
|
|
/* |
|
* Swap-space should not get truncated. Hence no need to plug the race |
|
* with invalidate/truncate. |
|
*/ |
|
spin_lock(&mapping->private_lock); |
|
if (!nfs_have_writebacks(inode) && |
|
NFS_PROTO(inode)->have_delegation(inode, FMODE_WRITE)) |
|
inode_inc_iversion_raw(inode); |
|
if (likely(!PageSwapCache(req->wb_page))) { |
|
set_bit(PG_MAPPED, &req->wb_flags); |
|
SetPagePrivate(req->wb_page); |
|
set_page_private(req->wb_page, (unsigned long)req); |
|
} |
|
spin_unlock(&mapping->private_lock); |
|
atomic_long_inc(&nfsi->nrequests); |
|
/* this a head request for a page group - mark it as having an |
|
* extra reference so sub groups can follow suit. |
|
* This flag also informs pgio layer when to bump nrequests when |
|
* adding subrequests. */ |
|
WARN_ON(test_and_set_bit(PG_INODE_REF, &req->wb_flags)); |
|
kref_get(&req->wb_kref); |
|
} |
|
|
|
/* |
|
* Remove a write request from an inode |
|
*/ |
|
static void nfs_inode_remove_request(struct nfs_page *req) |
|
{ |
|
struct address_space *mapping = page_file_mapping(req->wb_page); |
|
struct inode *inode = mapping->host; |
|
struct nfs_inode *nfsi = NFS_I(inode); |
|
struct nfs_page *head; |
|
|
|
if (nfs_page_group_sync_on_bit(req, PG_REMOVE)) { |
|
head = req->wb_head; |
|
|
|
spin_lock(&mapping->private_lock); |
|
if (likely(head->wb_page && !PageSwapCache(head->wb_page))) { |
|
set_page_private(head->wb_page, 0); |
|
ClearPagePrivate(head->wb_page); |
|
clear_bit(PG_MAPPED, &head->wb_flags); |
|
} |
|
spin_unlock(&mapping->private_lock); |
|
} |
|
|
|
if (test_and_clear_bit(PG_INODE_REF, &req->wb_flags)) { |
|
nfs_release_request(req); |
|
atomic_long_dec(&nfsi->nrequests); |
|
} |
|
} |
|
|
|
static void |
|
nfs_mark_request_dirty(struct nfs_page *req) |
|
{ |
|
if (req->wb_page) |
|
__set_page_dirty_nobuffers(req->wb_page); |
|
} |
|
|
|
/* |
|
* nfs_page_search_commits_for_head_request_locked |
|
* |
|
* Search through commit lists on @inode for the head request for @page. |
|
* Must be called while holding the inode (which is cinfo) lock. |
|
* |
|
* Returns the head request if found, or NULL if not found. |
|
*/ |
|
static struct nfs_page * |
|
nfs_page_search_commits_for_head_request_locked(struct nfs_inode *nfsi, |
|
struct page *page) |
|
{ |
|
struct nfs_page *freq, *t; |
|
struct nfs_commit_info cinfo; |
|
struct inode *inode = &nfsi->vfs_inode; |
|
|
|
nfs_init_cinfo_from_inode(&cinfo, inode); |
|
|
|
/* search through pnfs commit lists */ |
|
freq = pnfs_search_commit_reqs(inode, &cinfo, page); |
|
if (freq) |
|
return freq->wb_head; |
|
|
|
/* Linearly search the commit list for the correct request */ |
|
list_for_each_entry_safe(freq, t, &cinfo.mds->list, wb_list) { |
|
if (freq->wb_page == page) |
|
return freq->wb_head; |
|
} |
|
|
|
return NULL; |
|
} |
|
|
|
/** |
|
* nfs_request_add_commit_list_locked - add request to a commit list |
|
* @req: pointer to a struct nfs_page |
|
* @dst: commit list head |
|
* @cinfo: holds list lock and accounting info |
|
* |
|
* This sets the PG_CLEAN bit, updates the cinfo count of |
|
* number of outstanding requests requiring a commit as well as |
|
* the MM page stats. |
|
* |
|
* The caller must hold NFS_I(cinfo->inode)->commit_mutex, and the |
|
* nfs_page lock. |
|
*/ |
|
void |
|
nfs_request_add_commit_list_locked(struct nfs_page *req, struct list_head *dst, |
|
struct nfs_commit_info *cinfo) |
|
{ |
|
set_bit(PG_CLEAN, &req->wb_flags); |
|
nfs_list_add_request(req, dst); |
|
atomic_long_inc(&cinfo->mds->ncommit); |
|
} |
|
EXPORT_SYMBOL_GPL(nfs_request_add_commit_list_locked); |
|
|
|
/** |
|
* nfs_request_add_commit_list - add request to a commit list |
|
* @req: pointer to a struct nfs_page |
|
* @cinfo: holds list lock and accounting info |
|
* |
|
* This sets the PG_CLEAN bit, updates the cinfo count of |
|
* number of outstanding requests requiring a commit as well as |
|
* the MM page stats. |
|
* |
|
* The caller must _not_ hold the cinfo->lock, but must be |
|
* holding the nfs_page lock. |
|
*/ |
|
void |
|
nfs_request_add_commit_list(struct nfs_page *req, struct nfs_commit_info *cinfo) |
|
{ |
|
mutex_lock(&NFS_I(cinfo->inode)->commit_mutex); |
|
nfs_request_add_commit_list_locked(req, &cinfo->mds->list, cinfo); |
|
mutex_unlock(&NFS_I(cinfo->inode)->commit_mutex); |
|
if (req->wb_page) |
|
nfs_mark_page_unstable(req->wb_page, cinfo); |
|
} |
|
EXPORT_SYMBOL_GPL(nfs_request_add_commit_list); |
|
|
|
/** |
|
* nfs_request_remove_commit_list - Remove request from a commit list |
|
* @req: pointer to a nfs_page |
|
* @cinfo: holds list lock and accounting info |
|
* |
|
* This clears the PG_CLEAN bit, and updates the cinfo's count of |
|
* number of outstanding requests requiring a commit |
|
* It does not update the MM page stats. |
|
* |
|
* The caller _must_ hold the cinfo->lock and the nfs_page lock. |
|
*/ |
|
void |
|
nfs_request_remove_commit_list(struct nfs_page *req, |
|
struct nfs_commit_info *cinfo) |
|
{ |
|
if (!test_and_clear_bit(PG_CLEAN, &(req)->wb_flags)) |
|
return; |
|
nfs_list_remove_request(req); |
|
atomic_long_dec(&cinfo->mds->ncommit); |
|
} |
|
EXPORT_SYMBOL_GPL(nfs_request_remove_commit_list); |
|
|
|
static void nfs_init_cinfo_from_inode(struct nfs_commit_info *cinfo, |
|
struct inode *inode) |
|
{ |
|
cinfo->inode = inode; |
|
cinfo->mds = &NFS_I(inode)->commit_info; |
|
cinfo->ds = pnfs_get_ds_info(inode); |
|
cinfo->dreq = NULL; |
|
cinfo->completion_ops = &nfs_commit_completion_ops; |
|
} |
|
|
|
void nfs_init_cinfo(struct nfs_commit_info *cinfo, |
|
struct inode *inode, |
|
struct nfs_direct_req *dreq) |
|
{ |
|
if (dreq) |
|
nfs_init_cinfo_from_dreq(cinfo, dreq); |
|
else |
|
nfs_init_cinfo_from_inode(cinfo, inode); |
|
} |
|
EXPORT_SYMBOL_GPL(nfs_init_cinfo); |
|
|
|
/* |
|
* Add a request to the inode's commit list. |
|
*/ |
|
void |
|
nfs_mark_request_commit(struct nfs_page *req, struct pnfs_layout_segment *lseg, |
|
struct nfs_commit_info *cinfo, u32 ds_commit_idx) |
|
{ |
|
if (pnfs_mark_request_commit(req, lseg, cinfo, ds_commit_idx)) |
|
return; |
|
nfs_request_add_commit_list(req, cinfo); |
|
} |
|
|
|
static void |
|
nfs_clear_page_commit(struct page *page) |
|
{ |
|
dec_node_page_state(page, NR_WRITEBACK); |
|
dec_wb_stat(&inode_to_bdi(page_file_mapping(page)->host)->wb, |
|
WB_WRITEBACK); |
|
} |
|
|
|
/* Called holding the request lock on @req */ |
|
static void |
|
nfs_clear_request_commit(struct nfs_page *req) |
|
{ |
|
if (test_bit(PG_CLEAN, &req->wb_flags)) { |
|
struct nfs_open_context *ctx = nfs_req_openctx(req); |
|
struct inode *inode = d_inode(ctx->dentry); |
|
struct nfs_commit_info cinfo; |
|
|
|
nfs_init_cinfo_from_inode(&cinfo, inode); |
|
mutex_lock(&NFS_I(inode)->commit_mutex); |
|
if (!pnfs_clear_request_commit(req, &cinfo)) { |
|
nfs_request_remove_commit_list(req, &cinfo); |
|
} |
|
mutex_unlock(&NFS_I(inode)->commit_mutex); |
|
nfs_clear_page_commit(req->wb_page); |
|
} |
|
} |
|
|
|
int nfs_write_need_commit(struct nfs_pgio_header *hdr) |
|
{ |
|
if (hdr->verf.committed == NFS_DATA_SYNC) |
|
return hdr->lseg == NULL; |
|
return hdr->verf.committed != NFS_FILE_SYNC; |
|
} |
|
|
|
static void nfs_async_write_init(struct nfs_pgio_header *hdr) |
|
{ |
|
nfs_io_completion_get(hdr->io_completion); |
|
} |
|
|
|
static void nfs_write_completion(struct nfs_pgio_header *hdr) |
|
{ |
|
struct nfs_commit_info cinfo; |
|
unsigned long bytes = 0; |
|
|
|
if (test_bit(NFS_IOHDR_REDO, &hdr->flags)) |
|
goto out; |
|
nfs_init_cinfo_from_inode(&cinfo, hdr->inode); |
|
while (!list_empty(&hdr->pages)) { |
|
struct nfs_page *req = nfs_list_entry(hdr->pages.next); |
|
|
|
bytes += req->wb_bytes; |
|
nfs_list_remove_request(req); |
|
if (test_bit(NFS_IOHDR_ERROR, &hdr->flags) && |
|
(hdr->good_bytes < bytes)) { |
|
trace_nfs_comp_error(req, hdr->error); |
|
nfs_mapping_set_error(req->wb_page, hdr->error); |
|
goto remove_req; |
|
} |
|
if (nfs_write_need_commit(hdr)) { |
|
/* Reset wb_nio, since the write was successful. */ |
|
req->wb_nio = 0; |
|
memcpy(&req->wb_verf, &hdr->verf.verifier, sizeof(req->wb_verf)); |
|
nfs_mark_request_commit(req, hdr->lseg, &cinfo, |
|
hdr->pgio_mirror_idx); |
|
goto next; |
|
} |
|
remove_req: |
|
nfs_inode_remove_request(req); |
|
next: |
|
nfs_end_page_writeback(req); |
|
nfs_release_request(req); |
|
} |
|
out: |
|
nfs_io_completion_put(hdr->io_completion); |
|
hdr->release(hdr); |
|
} |
|
|
|
unsigned long |
|
nfs_reqs_to_commit(struct nfs_commit_info *cinfo) |
|
{ |
|
return atomic_long_read(&cinfo->mds->ncommit); |
|
} |
|
|
|
/* NFS_I(cinfo->inode)->commit_mutex held by caller */ |
|
int |
|
nfs_scan_commit_list(struct list_head *src, struct list_head *dst, |
|
struct nfs_commit_info *cinfo, int max) |
|
{ |
|
struct nfs_page *req, *tmp; |
|
int ret = 0; |
|
|
|
restart: |
|
list_for_each_entry_safe(req, tmp, src, wb_list) { |
|
kref_get(&req->wb_kref); |
|
if (!nfs_lock_request(req)) { |
|
int status; |
|
|
|
/* Prevent deadlock with nfs_lock_and_join_requests */ |
|
if (!list_empty(dst)) { |
|
nfs_release_request(req); |
|
continue; |
|
} |
|
/* Ensure we make progress to prevent livelock */ |
|
mutex_unlock(&NFS_I(cinfo->inode)->commit_mutex); |
|
status = nfs_wait_on_request(req); |
|
nfs_release_request(req); |
|
mutex_lock(&NFS_I(cinfo->inode)->commit_mutex); |
|
if (status < 0) |
|
break; |
|
goto restart; |
|
} |
|
nfs_request_remove_commit_list(req, cinfo); |
|
clear_bit(PG_COMMIT_TO_DS, &req->wb_flags); |
|
nfs_list_add_request(req, dst); |
|
ret++; |
|
if ((ret == max) && !cinfo->dreq) |
|
break; |
|
cond_resched(); |
|
} |
|
return ret; |
|
} |
|
EXPORT_SYMBOL_GPL(nfs_scan_commit_list); |
|
|
|
/* |
|
* nfs_scan_commit - Scan an inode for commit requests |
|
* @inode: NFS inode to scan |
|
* @dst: mds destination list |
|
* @cinfo: mds and ds lists of reqs ready to commit |
|
* |
|
* Moves requests from the inode's 'commit' request list. |
|
* The requests are *not* checked to ensure that they form a contiguous set. |
|
*/ |
|
int |
|
nfs_scan_commit(struct inode *inode, struct list_head *dst, |
|
struct nfs_commit_info *cinfo) |
|
{ |
|
int ret = 0; |
|
|
|
if (!atomic_long_read(&cinfo->mds->ncommit)) |
|
return 0; |
|
mutex_lock(&NFS_I(cinfo->inode)->commit_mutex); |
|
if (atomic_long_read(&cinfo->mds->ncommit) > 0) { |
|
const int max = INT_MAX; |
|
|
|
ret = nfs_scan_commit_list(&cinfo->mds->list, dst, |
|
cinfo, max); |
|
ret += pnfs_scan_commit_lists(inode, cinfo, max - ret); |
|
} |
|
mutex_unlock(&NFS_I(cinfo->inode)->commit_mutex); |
|
return ret; |
|
} |
|
|
|
/* |
|
* Search for an existing write request, and attempt to update |
|
* it to reflect a new dirty region on a given page. |
|
* |
|
* If the attempt fails, then the existing request is flushed out |
|
* to disk. |
|
*/ |
|
static struct nfs_page *nfs_try_to_update_request(struct inode *inode, |
|
struct page *page, |
|
unsigned int offset, |
|
unsigned int bytes) |
|
{ |
|
struct nfs_page *req; |
|
unsigned int rqend; |
|
unsigned int end; |
|
int error; |
|
|
|
end = offset + bytes; |
|
|
|
req = nfs_lock_and_join_requests(page); |
|
if (IS_ERR_OR_NULL(req)) |
|
return req; |
|
|
|
rqend = req->wb_offset + req->wb_bytes; |
|
/* |
|
* Tell the caller to flush out the request if |
|
* the offsets are non-contiguous. |
|
* Note: nfs_flush_incompatible() will already |
|
* have flushed out requests having wrong owners. |
|
*/ |
|
if (offset > rqend || end < req->wb_offset) |
|
goto out_flushme; |
|
|
|
/* Okay, the request matches. Update the region */ |
|
if (offset < req->wb_offset) { |
|
req->wb_offset = offset; |
|
req->wb_pgbase = offset; |
|
} |
|
if (end > rqend) |
|
req->wb_bytes = end - req->wb_offset; |
|
else |
|
req->wb_bytes = rqend - req->wb_offset; |
|
req->wb_nio = 0; |
|
return req; |
|
out_flushme: |
|
/* |
|
* Note: we mark the request dirty here because |
|
* nfs_lock_and_join_requests() cannot preserve |
|
* commit flags, so we have to replay the write. |
|
*/ |
|
nfs_mark_request_dirty(req); |
|
nfs_unlock_and_release_request(req); |
|
error = nfs_wb_page(inode, page); |
|
return (error < 0) ? ERR_PTR(error) : NULL; |
|
} |
|
|
|
/* |
|
* Try to update an existing write request, or create one if there is none. |
|
* |
|
* Note: Should always be called with the Page Lock held to prevent races |
|
* if we have to add a new request. Also assumes that the caller has |
|
* already called nfs_flush_incompatible() if necessary. |
|
*/ |
|
static struct nfs_page * nfs_setup_write_request(struct nfs_open_context* ctx, |
|
struct page *page, unsigned int offset, unsigned int bytes) |
|
{ |
|
struct inode *inode = page_file_mapping(page)->host; |
|
struct nfs_page *req; |
|
|
|
req = nfs_try_to_update_request(inode, page, offset, bytes); |
|
if (req != NULL) |
|
goto out; |
|
req = nfs_create_request(ctx, page, offset, bytes); |
|
if (IS_ERR(req)) |
|
goto out; |
|
nfs_inode_add_request(inode, req); |
|
out: |
|
return req; |
|
} |
|
|
|
static int nfs_writepage_setup(struct nfs_open_context *ctx, struct page *page, |
|
unsigned int offset, unsigned int count) |
|
{ |
|
struct nfs_page *req; |
|
|
|
req = nfs_setup_write_request(ctx, page, offset, count); |
|
if (IS_ERR(req)) |
|
return PTR_ERR(req); |
|
/* Update file length */ |
|
nfs_grow_file(page, offset, count); |
|
nfs_mark_uptodate(req); |
|
nfs_mark_request_dirty(req); |
|
nfs_unlock_and_release_request(req); |
|
return 0; |
|
} |
|
|
|
int nfs_flush_incompatible(struct file *file, struct page *page) |
|
{ |
|
struct nfs_open_context *ctx = nfs_file_open_context(file); |
|
struct nfs_lock_context *l_ctx; |
|
struct file_lock_context *flctx = file_inode(file)->i_flctx; |
|
struct nfs_page *req; |
|
int do_flush, status; |
|
/* |
|
* Look for a request corresponding to this page. If there |
|
* is one, and it belongs to another file, we flush it out |
|
* before we try to copy anything into the page. Do this |
|
* due to the lack of an ACCESS-type call in NFSv2. |
|
* Also do the same if we find a request from an existing |
|
* dropped page. |
|
*/ |
|
do { |
|
req = nfs_page_find_head_request(page); |
|
if (req == NULL) |
|
return 0; |
|
l_ctx = req->wb_lock_context; |
|
do_flush = req->wb_page != page || |
|
!nfs_match_open_context(nfs_req_openctx(req), ctx); |
|
if (l_ctx && flctx && |
|
!(list_empty_careful(&flctx->flc_posix) && |
|
list_empty_careful(&flctx->flc_flock))) { |
|
do_flush |= l_ctx->lockowner != current->files; |
|
} |
|
nfs_release_request(req); |
|
if (!do_flush) |
|
return 0; |
|
status = nfs_wb_page(page_file_mapping(page)->host, page); |
|
} while (status == 0); |
|
return status; |
|
} |
|
|
|
/* |
|
* Avoid buffered writes when a open context credential's key would |
|
* expire soon. |
|
* |
|
* Returns -EACCES if the key will expire within RPC_KEY_EXPIRE_FAIL. |
|
* |
|
* Return 0 and set a credential flag which triggers the inode to flush |
|
* and performs NFS_FILE_SYNC writes if the key will expired within |
|
* RPC_KEY_EXPIRE_TIMEO. |
|
*/ |
|
int |
|
nfs_key_timeout_notify(struct file *filp, struct inode *inode) |
|
{ |
|
struct nfs_open_context *ctx = nfs_file_open_context(filp); |
|
|
|
if (nfs_ctx_key_to_expire(ctx, inode) && |
|
!ctx->ll_cred) |
|
/* Already expired! */ |
|
return -EACCES; |
|
return 0; |
|
} |
|
|
|
/* |
|
* Test if the open context credential key is marked to expire soon. |
|
*/ |
|
bool nfs_ctx_key_to_expire(struct nfs_open_context *ctx, struct inode *inode) |
|
{ |
|
struct rpc_auth *auth = NFS_SERVER(inode)->client->cl_auth; |
|
struct rpc_cred *cred = ctx->ll_cred; |
|
struct auth_cred acred = { |
|
.cred = ctx->cred, |
|
}; |
|
|
|
if (cred && !cred->cr_ops->crmatch(&acred, cred, 0)) { |
|
put_rpccred(cred); |
|
ctx->ll_cred = NULL; |
|
cred = NULL; |
|
} |
|
if (!cred) |
|
cred = auth->au_ops->lookup_cred(auth, &acred, 0); |
|
if (!cred || IS_ERR(cred)) |
|
return true; |
|
ctx->ll_cred = cred; |
|
return !!(cred->cr_ops->crkey_timeout && |
|
cred->cr_ops->crkey_timeout(cred)); |
|
} |
|
|
|
/* |
|
* If the page cache is marked as unsafe or invalid, then we can't rely on |
|
* the PageUptodate() flag. In this case, we will need to turn off |
|
* write optimisations that depend on the page contents being correct. |
|
*/ |
|
static bool nfs_write_pageuptodate(struct page *page, struct inode *inode) |
|
{ |
|
struct nfs_inode *nfsi = NFS_I(inode); |
|
|
|
if (nfs_have_delegated_attributes(inode)) |
|
goto out; |
|
if (nfsi->cache_validity & NFS_INO_REVAL_PAGECACHE) |
|
return false; |
|
smp_rmb(); |
|
if (test_bit(NFS_INO_INVALIDATING, &nfsi->flags)) |
|
return false; |
|
out: |
|
if (nfsi->cache_validity & NFS_INO_INVALID_DATA) |
|
return false; |
|
return PageUptodate(page) != 0; |
|
} |
|
|
|
static bool |
|
is_whole_file_wrlock(struct file_lock *fl) |
|
{ |
|
return fl->fl_start == 0 && fl->fl_end == OFFSET_MAX && |
|
fl->fl_type == F_WRLCK; |
|
} |
|
|
|
/* If we know the page is up to date, and we're not using byte range locks (or |
|
* if we have the whole file locked for writing), it may be more efficient to |
|
* extend the write to cover the entire page in order to avoid fragmentation |
|
* inefficiencies. |
|
* |
|
* If the file is opened for synchronous writes then we can just skip the rest |
|
* of the checks. |
|
*/ |
|
static int nfs_can_extend_write(struct file *file, struct page *page, struct inode *inode) |
|
{ |
|
int ret; |
|
struct file_lock_context *flctx = inode->i_flctx; |
|
struct file_lock *fl; |
|
|
|
if (file->f_flags & O_DSYNC) |
|
return 0; |
|
if (!nfs_write_pageuptodate(page, inode)) |
|
return 0; |
|
if (NFS_PROTO(inode)->have_delegation(inode, FMODE_WRITE)) |
|
return 1; |
|
if (!flctx || (list_empty_careful(&flctx->flc_flock) && |
|
list_empty_careful(&flctx->flc_posix))) |
|
return 1; |
|
|
|
/* Check to see if there are whole file write locks */ |
|
ret = 0; |
|
spin_lock(&flctx->flc_lock); |
|
if (!list_empty(&flctx->flc_posix)) { |
|
fl = list_first_entry(&flctx->flc_posix, struct file_lock, |
|
fl_list); |
|
if (is_whole_file_wrlock(fl)) |
|
ret = 1; |
|
} else if (!list_empty(&flctx->flc_flock)) { |
|
fl = list_first_entry(&flctx->flc_flock, struct file_lock, |
|
fl_list); |
|
if (fl->fl_type == F_WRLCK) |
|
ret = 1; |
|
} |
|
spin_unlock(&flctx->flc_lock); |
|
return ret; |
|
} |
|
|
|
/* |
|
* Update and possibly write a cached page of an NFS file. |
|
* |
|
* XXX: Keep an eye on generic_file_read to make sure it doesn't do bad |
|
* things with a page scheduled for an RPC call (e.g. invalidate it). |
|
*/ |
|
int nfs_updatepage(struct file *file, struct page *page, |
|
unsigned int offset, unsigned int count) |
|
{ |
|
struct nfs_open_context *ctx = nfs_file_open_context(file); |
|
struct address_space *mapping = page_file_mapping(page); |
|
struct inode *inode = mapping->host; |
|
int status = 0; |
|
|
|
nfs_inc_stats(inode, NFSIOS_VFSUPDATEPAGE); |
|
|
|
dprintk("NFS: nfs_updatepage(%pD2 %d@%lld)\n", |
|
file, count, (long long)(page_file_offset(page) + offset)); |
|
|
|
if (!count) |
|
goto out; |
|
|
|
if (nfs_can_extend_write(file, page, inode)) { |
|
count = max(count + offset, nfs_page_length(page)); |
|
offset = 0; |
|
} |
|
|
|
status = nfs_writepage_setup(ctx, page, offset, count); |
|
if (status < 0) |
|
nfs_set_pageerror(mapping); |
|
else |
|
__set_page_dirty_nobuffers(page); |
|
out: |
|
dprintk("NFS: nfs_updatepage returns %d (isize %lld)\n", |
|
status, (long long)i_size_read(inode)); |
|
return status; |
|
} |
|
|
|
static int flush_task_priority(int how) |
|
{ |
|
switch (how & (FLUSH_HIGHPRI|FLUSH_LOWPRI)) { |
|
case FLUSH_HIGHPRI: |
|
return RPC_PRIORITY_HIGH; |
|
case FLUSH_LOWPRI: |
|
return RPC_PRIORITY_LOW; |
|
} |
|
return RPC_PRIORITY_NORMAL; |
|
} |
|
|
|
static void nfs_initiate_write(struct nfs_pgio_header *hdr, |
|
struct rpc_message *msg, |
|
const struct nfs_rpc_ops *rpc_ops, |
|
struct rpc_task_setup *task_setup_data, int how) |
|
{ |
|
int priority = flush_task_priority(how); |
|
|
|
task_setup_data->priority = priority; |
|
rpc_ops->write_setup(hdr, msg, &task_setup_data->rpc_client); |
|
trace_nfs_initiate_write(hdr); |
|
} |
|
|
|
/* If a nfs_flush_* function fails, it should remove reqs from @head and |
|
* call this on each, which will prepare them to be retried on next |
|
* writeback using standard nfs. |
|
*/ |
|
static void nfs_redirty_request(struct nfs_page *req) |
|
{ |
|
/* Bump the transmission count */ |
|
req->wb_nio++; |
|
nfs_mark_request_dirty(req); |
|
set_bit(NFS_CONTEXT_RESEND_WRITES, &nfs_req_openctx(req)->flags); |
|
nfs_end_page_writeback(req); |
|
nfs_release_request(req); |
|
} |
|
|
|
static void nfs_async_write_error(struct list_head *head, int error) |
|
{ |
|
struct nfs_page *req; |
|
|
|
while (!list_empty(head)) { |
|
req = nfs_list_entry(head->next); |
|
nfs_list_remove_request(req); |
|
if (nfs_error_is_fatal(error)) |
|
nfs_write_error(req, error); |
|
else |
|
nfs_redirty_request(req); |
|
} |
|
} |
|
|
|
static void nfs_async_write_reschedule_io(struct nfs_pgio_header *hdr) |
|
{ |
|
nfs_async_write_error(&hdr->pages, 0); |
|
filemap_fdatawrite_range(hdr->inode->i_mapping, hdr->args.offset, |
|
hdr->args.offset + hdr->args.count - 1); |
|
} |
|
|
|
static const struct nfs_pgio_completion_ops nfs_async_write_completion_ops = { |
|
.init_hdr = nfs_async_write_init, |
|
.error_cleanup = nfs_async_write_error, |
|
.completion = nfs_write_completion, |
|
.reschedule_io = nfs_async_write_reschedule_io, |
|
}; |
|
|
|
void nfs_pageio_init_write(struct nfs_pageio_descriptor *pgio, |
|
struct inode *inode, int ioflags, bool force_mds, |
|
const struct nfs_pgio_completion_ops *compl_ops) |
|
{ |
|
struct nfs_server *server = NFS_SERVER(inode); |
|
const struct nfs_pageio_ops *pg_ops = &nfs_pgio_rw_ops; |
|
|
|
#ifdef CONFIG_NFS_V4_1 |
|
if (server->pnfs_curr_ld && !force_mds) |
|
pg_ops = server->pnfs_curr_ld->pg_write_ops; |
|
#endif |
|
nfs_pageio_init(pgio, inode, pg_ops, compl_ops, &nfs_rw_write_ops, |
|
server->wsize, ioflags); |
|
} |
|
EXPORT_SYMBOL_GPL(nfs_pageio_init_write); |
|
|
|
void nfs_pageio_reset_write_mds(struct nfs_pageio_descriptor *pgio) |
|
{ |
|
struct nfs_pgio_mirror *mirror; |
|
|
|
if (pgio->pg_ops && pgio->pg_ops->pg_cleanup) |
|
pgio->pg_ops->pg_cleanup(pgio); |
|
|
|
pgio->pg_ops = &nfs_pgio_rw_ops; |
|
|
|
nfs_pageio_stop_mirroring(pgio); |
|
|
|
mirror = &pgio->pg_mirrors[0]; |
|
mirror->pg_bsize = NFS_SERVER(pgio->pg_inode)->wsize; |
|
} |
|
EXPORT_SYMBOL_GPL(nfs_pageio_reset_write_mds); |
|
|
|
|
|
void nfs_commit_prepare(struct rpc_task *task, void *calldata) |
|
{ |
|
struct nfs_commit_data *data = calldata; |
|
|
|
NFS_PROTO(data->inode)->commit_rpc_prepare(task, data); |
|
} |
|
|
|
/* |
|
* Special version of should_remove_suid() that ignores capabilities. |
|
*/ |
|
static int nfs_should_remove_suid(const struct inode *inode) |
|
{ |
|
umode_t mode = inode->i_mode; |
|
int kill = 0; |
|
|
|
/* suid always must be killed */ |
|
if (unlikely(mode & S_ISUID)) |
|
kill = ATTR_KILL_SUID; |
|
|
|
/* |
|
* sgid without any exec bits is just a mandatory locking mark; leave |
|
* it alone. If some exec bits are set, it's a real sgid; kill it. |
|
*/ |
|
if (unlikely((mode & S_ISGID) && (mode & S_IXGRP))) |
|
kill |= ATTR_KILL_SGID; |
|
|
|
if (unlikely(kill && S_ISREG(mode))) |
|
return kill; |
|
|
|
return 0; |
|
} |
|
|
|
static void nfs_writeback_check_extend(struct nfs_pgio_header *hdr, |
|
struct nfs_fattr *fattr) |
|
{ |
|
struct nfs_pgio_args *argp = &hdr->args; |
|
struct nfs_pgio_res *resp = &hdr->res; |
|
u64 size = argp->offset + resp->count; |
|
|
|
if (!(fattr->valid & NFS_ATTR_FATTR_SIZE)) |
|
fattr->size = size; |
|
if (nfs_size_to_loff_t(fattr->size) < i_size_read(hdr->inode)) { |
|
fattr->valid &= ~NFS_ATTR_FATTR_SIZE; |
|
return; |
|
} |
|
if (size != fattr->size) |
|
return; |
|
/* Set attribute barrier */ |
|
nfs_fattr_set_barrier(fattr); |
|
/* ...and update size */ |
|
fattr->valid |= NFS_ATTR_FATTR_SIZE; |
|
} |
|
|
|
void nfs_writeback_update_inode(struct nfs_pgio_header *hdr) |
|
{ |
|
struct nfs_fattr *fattr = &hdr->fattr; |
|
struct inode *inode = hdr->inode; |
|
|
|
spin_lock(&inode->i_lock); |
|
nfs_writeback_check_extend(hdr, fattr); |
|
nfs_post_op_update_inode_force_wcc_locked(inode, fattr); |
|
spin_unlock(&inode->i_lock); |
|
} |
|
EXPORT_SYMBOL_GPL(nfs_writeback_update_inode); |
|
|
|
/* |
|
* This function is called when the WRITE call is complete. |
|
*/ |
|
static int nfs_writeback_done(struct rpc_task *task, |
|
struct nfs_pgio_header *hdr, |
|
struct inode *inode) |
|
{ |
|
int status; |
|
|
|
/* |
|
* ->write_done will attempt to use post-op attributes to detect |
|
* conflicting writes by other clients. A strict interpretation |
|
* of close-to-open would allow us to continue caching even if |
|
* another writer had changed the file, but some applications |
|
* depend on tighter cache coherency when writing. |
|
*/ |
|
status = NFS_PROTO(inode)->write_done(task, hdr); |
|
if (status != 0) |
|
return status; |
|
|
|
nfs_add_stats(inode, NFSIOS_SERVERWRITTENBYTES, hdr->res.count); |
|
trace_nfs_writeback_done(task, hdr); |
|
|
|
if (hdr->res.verf->committed < hdr->args.stable && |
|
task->tk_status >= 0) { |
|
/* We tried a write call, but the server did not |
|
* commit data to stable storage even though we |
|
* requested it. |
|
* Note: There is a known bug in Tru64 < 5.0 in which |
|
* the server reports NFS_DATA_SYNC, but performs |
|
* NFS_FILE_SYNC. We therefore implement this checking |
|
* as a dprintk() in order to avoid filling syslog. |
|
*/ |
|
static unsigned long complain; |
|
|
|
/* Note this will print the MDS for a DS write */ |
|
if (time_before(complain, jiffies)) { |
|
dprintk("NFS: faulty NFS server %s:" |
|
" (committed = %d) != (stable = %d)\n", |
|
NFS_SERVER(inode)->nfs_client->cl_hostname, |
|
hdr->res.verf->committed, hdr->args.stable); |
|
complain = jiffies + 300 * HZ; |
|
} |
|
} |
|
|
|
/* Deal with the suid/sgid bit corner case */ |
|
if (nfs_should_remove_suid(inode)) { |
|
spin_lock(&inode->i_lock); |
|
NFS_I(inode)->cache_validity |= NFS_INO_INVALID_OTHER; |
|
spin_unlock(&inode->i_lock); |
|
} |
|
return 0; |
|
} |
|
|
|
/* |
|
* This function is called when the WRITE call is complete. |
|
*/ |
|
static void nfs_writeback_result(struct rpc_task *task, |
|
struct nfs_pgio_header *hdr) |
|
{ |
|
struct nfs_pgio_args *argp = &hdr->args; |
|
struct nfs_pgio_res *resp = &hdr->res; |
|
|
|
if (resp->count < argp->count) { |
|
static unsigned long complain; |
|
|
|
/* This a short write! */ |
|
nfs_inc_stats(hdr->inode, NFSIOS_SHORTWRITE); |
|
|
|
/* Has the server at least made some progress? */ |
|
if (resp->count == 0) { |
|
if (time_before(complain, jiffies)) { |
|
printk(KERN_WARNING |
|
"NFS: Server wrote zero bytes, expected %u.\n", |
|
argp->count); |
|
complain = jiffies + 300 * HZ; |
|
} |
|
nfs_set_pgio_error(hdr, -EIO, argp->offset); |
|
task->tk_status = -EIO; |
|
return; |
|
} |
|
|
|
/* For non rpc-based layout drivers, retry-through-MDS */ |
|
if (!task->tk_ops) { |
|
hdr->pnfs_error = -EAGAIN; |
|
return; |
|
} |
|
|
|
/* Was this an NFSv2 write or an NFSv3 stable write? */ |
|
if (resp->verf->committed != NFS_UNSTABLE) { |
|
/* Resend from where the server left off */ |
|
hdr->mds_offset += resp->count; |
|
argp->offset += resp->count; |
|
argp->pgbase += resp->count; |
|
argp->count -= resp->count; |
|
} else { |
|
/* Resend as a stable write in order to avoid |
|
* headaches in the case of a server crash. |
|
*/ |
|
argp->stable = NFS_FILE_SYNC; |
|
} |
|
resp->count = 0; |
|
resp->verf->committed = 0; |
|
rpc_restart_call_prepare(task); |
|
} |
|
} |
|
|
|
static int wait_on_commit(struct nfs_mds_commit_info *cinfo) |
|
{ |
|
return wait_var_event_killable(&cinfo->rpcs_out, |
|
!atomic_read(&cinfo->rpcs_out)); |
|
} |
|
|
|
static void nfs_commit_begin(struct nfs_mds_commit_info *cinfo) |
|
{ |
|
atomic_inc(&cinfo->rpcs_out); |
|
} |
|
|
|
static void nfs_commit_end(struct nfs_mds_commit_info *cinfo) |
|
{ |
|
if (atomic_dec_and_test(&cinfo->rpcs_out)) |
|
wake_up_var(&cinfo->rpcs_out); |
|
} |
|
|
|
void nfs_commitdata_release(struct nfs_commit_data *data) |
|
{ |
|
put_nfs_open_context(data->context); |
|
nfs_commit_free(data); |
|
} |
|
EXPORT_SYMBOL_GPL(nfs_commitdata_release); |
|
|
|
int nfs_initiate_commit(struct rpc_clnt *clnt, struct nfs_commit_data *data, |
|
const struct nfs_rpc_ops *nfs_ops, |
|
const struct rpc_call_ops *call_ops, |
|
int how, int flags) |
|
{ |
|
struct rpc_task *task; |
|
int priority = flush_task_priority(how); |
|
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 | flags, |
|
.priority = priority, |
|
}; |
|
/* Set up the initial task struct. */ |
|
nfs_ops->commit_setup(data, &msg, &task_setup_data.rpc_client); |
|
trace_nfs_initiate_commit(data); |
|
|
|
dprintk("NFS: initiated commit call\n"); |
|
|
|
task = rpc_run_task(&task_setup_data); |
|
if (IS_ERR(task)) |
|
return PTR_ERR(task); |
|
if (how & FLUSH_SYNC) |
|
rpc_wait_for_completion_task(task); |
|
rpc_put_task(task); |
|
return 0; |
|
} |
|
EXPORT_SYMBOL_GPL(nfs_initiate_commit); |
|
|
|
static loff_t nfs_get_lwb(struct list_head *head) |
|
{ |
|
loff_t lwb = 0; |
|
struct nfs_page *req; |
|
|
|
list_for_each_entry(req, head, wb_list) |
|
if (lwb < (req_offset(req) + req->wb_bytes)) |
|
lwb = req_offset(req) + req->wb_bytes; |
|
|
|
return lwb; |
|
} |
|
|
|
/* |
|
* Set up the argument/result storage required for the RPC call. |
|
*/ |
|
void nfs_init_commit(struct nfs_commit_data *data, |
|
struct list_head *head, |
|
struct pnfs_layout_segment *lseg, |
|
struct nfs_commit_info *cinfo) |
|
{ |
|
struct nfs_page *first; |
|
struct nfs_open_context *ctx; |
|
struct inode *inode; |
|
|
|
/* Set up the RPC argument and reply structs |
|
* NB: take care not to mess about with data->commit et al. */ |
|
|
|
if (head) |
|
list_splice_init(head, &data->pages); |
|
|
|
first = nfs_list_entry(data->pages.next); |
|
ctx = nfs_req_openctx(first); |
|
inode = d_inode(ctx->dentry); |
|
|
|
data->inode = inode; |
|
data->cred = ctx->cred; |
|
data->lseg = lseg; /* reference transferred */ |
|
/* only set lwb for pnfs commit */ |
|
if (lseg) |
|
data->lwb = nfs_get_lwb(&data->pages); |
|
data->mds_ops = &nfs_commit_ops; |
|
data->completion_ops = cinfo->completion_ops; |
|
data->dreq = cinfo->dreq; |
|
|
|
data->args.fh = NFS_FH(data->inode); |
|
/* Note: we always request a commit of the entire inode */ |
|
data->args.offset = 0; |
|
data->args.count = 0; |
|
data->context = get_nfs_open_context(ctx); |
|
data->res.fattr = &data->fattr; |
|
data->res.verf = &data->verf; |
|
nfs_fattr_init(&data->fattr); |
|
} |
|
EXPORT_SYMBOL_GPL(nfs_init_commit); |
|
|
|
void nfs_retry_commit(struct list_head *page_list, |
|
struct pnfs_layout_segment *lseg, |
|
struct nfs_commit_info *cinfo, |
|
u32 ds_commit_idx) |
|
{ |
|
struct nfs_page *req; |
|
|
|
while (!list_empty(page_list)) { |
|
req = nfs_list_entry(page_list->next); |
|
nfs_list_remove_request(req); |
|
nfs_mark_request_commit(req, lseg, cinfo, ds_commit_idx); |
|
if (!cinfo->dreq) |
|
nfs_clear_page_commit(req->wb_page); |
|
nfs_unlock_and_release_request(req); |
|
} |
|
} |
|
EXPORT_SYMBOL_GPL(nfs_retry_commit); |
|
|
|
static void |
|
nfs_commit_resched_write(struct nfs_commit_info *cinfo, |
|
struct nfs_page *req) |
|
{ |
|
__set_page_dirty_nobuffers(req->wb_page); |
|
} |
|
|
|
/* |
|
* Commit dirty pages |
|
*/ |
|
static int |
|
nfs_commit_list(struct inode *inode, struct list_head *head, int how, |
|
struct nfs_commit_info *cinfo) |
|
{ |
|
struct nfs_commit_data *data; |
|
|
|
/* another commit raced with us */ |
|
if (list_empty(head)) |
|
return 0; |
|
|
|
data = nfs_commitdata_alloc(true); |
|
|
|
/* Set up the argument struct */ |
|
nfs_init_commit(data, head, NULL, cinfo); |
|
atomic_inc(&cinfo->mds->rpcs_out); |
|
return nfs_initiate_commit(NFS_CLIENT(inode), data, NFS_PROTO(inode), |
|
data->mds_ops, how, RPC_TASK_CRED_NOREF); |
|
} |
|
|
|
/* |
|
* COMMIT call returned |
|
*/ |
|
static void nfs_commit_done(struct rpc_task *task, void *calldata) |
|
{ |
|
struct nfs_commit_data *data = calldata; |
|
|
|
dprintk("NFS: %5u nfs_commit_done (status %d)\n", |
|
task->tk_pid, task->tk_status); |
|
|
|
/* Call the NFS version-specific code */ |
|
NFS_PROTO(data->inode)->commit_done(task, data); |
|
trace_nfs_commit_done(task, data); |
|
} |
|
|
|
static void nfs_commit_release_pages(struct nfs_commit_data *data) |
|
{ |
|
const struct nfs_writeverf *verf = data->res.verf; |
|
struct nfs_page *req; |
|
int status = data->task.tk_status; |
|
struct nfs_commit_info cinfo; |
|
struct nfs_server *nfss; |
|
|
|
while (!list_empty(&data->pages)) { |
|
req = nfs_list_entry(data->pages.next); |
|
nfs_list_remove_request(req); |
|
if (req->wb_page) |
|
nfs_clear_page_commit(req->wb_page); |
|
|
|
dprintk("NFS: commit (%s/%llu %d@%lld)", |
|
nfs_req_openctx(req)->dentry->d_sb->s_id, |
|
(unsigned long long)NFS_FILEID(d_inode(nfs_req_openctx(req)->dentry)), |
|
req->wb_bytes, |
|
(long long)req_offset(req)); |
|
if (status < 0) { |
|
if (req->wb_page) { |
|
trace_nfs_commit_error(req, status); |
|
nfs_mapping_set_error(req->wb_page, status); |
|
nfs_inode_remove_request(req); |
|
} |
|
dprintk_cont(", error = %d\n", status); |
|
goto next; |
|
} |
|
|
|
/* Okay, COMMIT succeeded, apparently. Check the verifier |
|
* returned by the server against all stored verfs. */ |
|
if (nfs_write_match_verf(verf, req)) { |
|
/* We have a match */ |
|
if (req->wb_page) |
|
nfs_inode_remove_request(req); |
|
dprintk_cont(" OK\n"); |
|
goto next; |
|
} |
|
/* We have a mismatch. Write the page again */ |
|
dprintk_cont(" mismatch\n"); |
|
nfs_mark_request_dirty(req); |
|
set_bit(NFS_CONTEXT_RESEND_WRITES, &nfs_req_openctx(req)->flags); |
|
next: |
|
nfs_unlock_and_release_request(req); |
|
/* Latency breaker */ |
|
cond_resched(); |
|
} |
|
nfss = NFS_SERVER(data->inode); |
|
if (atomic_long_read(&nfss->writeback) < NFS_CONGESTION_OFF_THRESH) |
|
clear_bdi_congested(inode_to_bdi(data->inode), BLK_RW_ASYNC); |
|
|
|
nfs_init_cinfo(&cinfo, data->inode, data->dreq); |
|
nfs_commit_end(cinfo.mds); |
|
} |
|
|
|
static void nfs_commit_release(void *calldata) |
|
{ |
|
struct nfs_commit_data *data = calldata; |
|
|
|
data->completion_ops->completion(data); |
|
nfs_commitdata_release(calldata); |
|
} |
|
|
|
static const struct rpc_call_ops nfs_commit_ops = { |
|
.rpc_call_prepare = nfs_commit_prepare, |
|
.rpc_call_done = nfs_commit_done, |
|
.rpc_release = nfs_commit_release, |
|
}; |
|
|
|
static const struct nfs_commit_completion_ops nfs_commit_completion_ops = { |
|
.completion = nfs_commit_release_pages, |
|
.resched_write = nfs_commit_resched_write, |
|
}; |
|
|
|
int nfs_generic_commit_list(struct inode *inode, struct list_head *head, |
|
int how, struct nfs_commit_info *cinfo) |
|
{ |
|
int status; |
|
|
|
status = pnfs_commit_list(inode, head, how, cinfo); |
|
if (status == PNFS_NOT_ATTEMPTED) |
|
status = nfs_commit_list(inode, head, how, cinfo); |
|
return status; |
|
} |
|
|
|
static int __nfs_commit_inode(struct inode *inode, int how, |
|
struct writeback_control *wbc) |
|
{ |
|
LIST_HEAD(head); |
|
struct nfs_commit_info cinfo; |
|
int may_wait = how & FLUSH_SYNC; |
|
int ret, nscan; |
|
|
|
nfs_init_cinfo_from_inode(&cinfo, inode); |
|
nfs_commit_begin(cinfo.mds); |
|
for (;;) { |
|
ret = nscan = nfs_scan_commit(inode, &head, &cinfo); |
|
if (ret <= 0) |
|
break; |
|
ret = nfs_generic_commit_list(inode, &head, how, &cinfo); |
|
if (ret < 0) |
|
break; |
|
ret = 0; |
|
if (wbc && wbc->sync_mode == WB_SYNC_NONE) { |
|
if (nscan < wbc->nr_to_write) |
|
wbc->nr_to_write -= nscan; |
|
else |
|
wbc->nr_to_write = 0; |
|
} |
|
if (nscan < INT_MAX) |
|
break; |
|
cond_resched(); |
|
} |
|
nfs_commit_end(cinfo.mds); |
|
if (ret || !may_wait) |
|
return ret; |
|
return wait_on_commit(cinfo.mds); |
|
} |
|
|
|
int nfs_commit_inode(struct inode *inode, int how) |
|
{ |
|
return __nfs_commit_inode(inode, how, NULL); |
|
} |
|
EXPORT_SYMBOL_GPL(nfs_commit_inode); |
|
|
|
int nfs_write_inode(struct inode *inode, struct writeback_control *wbc) |
|
{ |
|
struct nfs_inode *nfsi = NFS_I(inode); |
|
int flags = FLUSH_SYNC; |
|
int ret = 0; |
|
|
|
if (wbc->sync_mode == WB_SYNC_NONE) { |
|
/* no commits means nothing needs to be done */ |
|
if (!atomic_long_read(&nfsi->commit_info.ncommit)) |
|
goto check_requests_outstanding; |
|
|
|
/* Don't commit yet if this is a non-blocking flush and there |
|
* are a lot of outstanding writes for this mapping. |
|
*/ |
|
if (mapping_tagged(inode->i_mapping, PAGECACHE_TAG_WRITEBACK)) |
|
goto out_mark_dirty; |
|
|
|
/* don't wait for the COMMIT response */ |
|
flags = 0; |
|
} |
|
|
|
ret = __nfs_commit_inode(inode, flags, wbc); |
|
if (!ret) { |
|
if (flags & FLUSH_SYNC) |
|
return 0; |
|
} else if (atomic_long_read(&nfsi->commit_info.ncommit)) |
|
goto out_mark_dirty; |
|
|
|
check_requests_outstanding: |
|
if (!atomic_read(&nfsi->commit_info.rpcs_out)) |
|
return ret; |
|
out_mark_dirty: |
|
__mark_inode_dirty(inode, I_DIRTY_DATASYNC); |
|
return ret; |
|
} |
|
EXPORT_SYMBOL_GPL(nfs_write_inode); |
|
|
|
/* |
|
* Wrapper for filemap_write_and_wait_range() |
|
* |
|
* Needed for pNFS in order to ensure data becomes visible to the |
|
* client. |
|
*/ |
|
int nfs_filemap_write_and_wait_range(struct address_space *mapping, |
|
loff_t lstart, loff_t lend) |
|
{ |
|
int ret; |
|
|
|
ret = filemap_write_and_wait_range(mapping, lstart, lend); |
|
if (ret == 0) |
|
ret = pnfs_sync_inode(mapping->host, true); |
|
return ret; |
|
} |
|
EXPORT_SYMBOL_GPL(nfs_filemap_write_and_wait_range); |
|
|
|
/* |
|
* flush the inode to disk. |
|
*/ |
|
int nfs_wb_all(struct inode *inode) |
|
{ |
|
int ret; |
|
|
|
trace_nfs_writeback_inode_enter(inode); |
|
|
|
ret = filemap_write_and_wait(inode->i_mapping); |
|
if (ret) |
|
goto out; |
|
ret = nfs_commit_inode(inode, FLUSH_SYNC); |
|
if (ret < 0) |
|
goto out; |
|
pnfs_sync_inode(inode, true); |
|
ret = 0; |
|
|
|
out: |
|
trace_nfs_writeback_inode_exit(inode, ret); |
|
return ret; |
|
} |
|
EXPORT_SYMBOL_GPL(nfs_wb_all); |
|
|
|
int nfs_wb_page_cancel(struct inode *inode, struct page *page) |
|
{ |
|
struct nfs_page *req; |
|
int ret = 0; |
|
|
|
wait_on_page_writeback(page); |
|
|
|
/* blocking call to cancel all requests and join to a single (head) |
|
* request */ |
|
req = nfs_lock_and_join_requests(page); |
|
|
|
if (IS_ERR(req)) { |
|
ret = PTR_ERR(req); |
|
} else if (req) { |
|
/* all requests from this page have been cancelled by |
|
* nfs_lock_and_join_requests, so just remove the head |
|
* request from the inode / page_private pointer and |
|
* release it */ |
|
nfs_inode_remove_request(req); |
|
nfs_unlock_and_release_request(req); |
|
} |
|
|
|
return ret; |
|
} |
|
|
|
/* |
|
* Write back all requests on one page - we do this before reading it. |
|
*/ |
|
int nfs_wb_page(struct inode *inode, struct page *page) |
|
{ |
|
loff_t range_start = page_file_offset(page); |
|
loff_t range_end = range_start + (loff_t)(PAGE_SIZE - 1); |
|
struct writeback_control wbc = { |
|
.sync_mode = WB_SYNC_ALL, |
|
.nr_to_write = 0, |
|
.range_start = range_start, |
|
.range_end = range_end, |
|
}; |
|
int ret; |
|
|
|
trace_nfs_writeback_page_enter(inode); |
|
|
|
for (;;) { |
|
wait_on_page_writeback(page); |
|
if (clear_page_dirty_for_io(page)) { |
|
ret = nfs_writepage_locked(page, &wbc); |
|
if (ret < 0) |
|
goto out_error; |
|
continue; |
|
} |
|
ret = 0; |
|
if (!PagePrivate(page)) |
|
break; |
|
ret = nfs_commit_inode(inode, FLUSH_SYNC); |
|
if (ret < 0) |
|
goto out_error; |
|
} |
|
out_error: |
|
trace_nfs_writeback_page_exit(inode, ret); |
|
return ret; |
|
} |
|
|
|
#ifdef CONFIG_MIGRATION |
|
int nfs_migrate_page(struct address_space *mapping, struct page *newpage, |
|
struct page *page, enum migrate_mode mode) |
|
{ |
|
/* |
|
* If PagePrivate is set, then the page is currently associated with |
|
* an in-progress read or write request. Don't try to migrate it. |
|
* |
|
* FIXME: we could do this in principle, but we'll need a way to ensure |
|
* that we can safely release the inode reference while holding |
|
* the page lock. |
|
*/ |
|
if (PagePrivate(page)) |
|
return -EBUSY; |
|
|
|
if (!nfs_fscache_release_page(page, GFP_KERNEL)) |
|
return -EBUSY; |
|
|
|
return migrate_page(mapping, newpage, page, mode); |
|
} |
|
#endif |
|
|
|
int __init nfs_init_writepagecache(void) |
|
{ |
|
nfs_wdata_cachep = kmem_cache_create("nfs_write_data", |
|
sizeof(struct nfs_pgio_header), |
|
0, SLAB_HWCACHE_ALIGN, |
|
NULL); |
|
if (nfs_wdata_cachep == NULL) |
|
return -ENOMEM; |
|
|
|
nfs_wdata_mempool = mempool_create_slab_pool(MIN_POOL_WRITE, |
|
nfs_wdata_cachep); |
|
if (nfs_wdata_mempool == NULL) |
|
goto out_destroy_write_cache; |
|
|
|
nfs_cdata_cachep = kmem_cache_create("nfs_commit_data", |
|
sizeof(struct nfs_commit_data), |
|
0, SLAB_HWCACHE_ALIGN, |
|
NULL); |
|
if (nfs_cdata_cachep == NULL) |
|
goto out_destroy_write_mempool; |
|
|
|
nfs_commit_mempool = mempool_create_slab_pool(MIN_POOL_COMMIT, |
|
nfs_cdata_cachep); |
|
if (nfs_commit_mempool == NULL) |
|
goto out_destroy_commit_cache; |
|
|
|
/* |
|
* NFS congestion size, scale with available memory. |
|
* |
|
* 64MB: 8192k |
|
* 128MB: 11585k |
|
* 256MB: 16384k |
|
* 512MB: 23170k |
|
* 1GB: 32768k |
|
* 2GB: 46340k |
|
* 4GB: 65536k |
|
* 8GB: 92681k |
|
* 16GB: 131072k |
|
* |
|
* This allows larger machines to have larger/more transfers. |
|
* Limit the default to 256M |
|
*/ |
|
nfs_congestion_kb = (16*int_sqrt(totalram_pages())) << (PAGE_SHIFT-10); |
|
if (nfs_congestion_kb > 256*1024) |
|
nfs_congestion_kb = 256*1024; |
|
|
|
return 0; |
|
|
|
out_destroy_commit_cache: |
|
kmem_cache_destroy(nfs_cdata_cachep); |
|
out_destroy_write_mempool: |
|
mempool_destroy(nfs_wdata_mempool); |
|
out_destroy_write_cache: |
|
kmem_cache_destroy(nfs_wdata_cachep); |
|
return -ENOMEM; |
|
} |
|
|
|
void nfs_destroy_writepagecache(void) |
|
{ |
|
mempool_destroy(nfs_commit_mempool); |
|
kmem_cache_destroy(nfs_cdata_cachep); |
|
mempool_destroy(nfs_wdata_mempool); |
|
kmem_cache_destroy(nfs_wdata_cachep); |
|
} |
|
|
|
static const struct nfs_rw_ops nfs_rw_write_ops = { |
|
.rw_alloc_header = nfs_writehdr_alloc, |
|
.rw_free_header = nfs_writehdr_free, |
|
.rw_done = nfs_writeback_done, |
|
.rw_result = nfs_writeback_result, |
|
.rw_initiate = nfs_initiate_write, |
|
};
|
|
|