diff options
Diffstat (limited to 'fs/nfs/write.c')
| -rw-r--r-- | fs/nfs/write.c | 951 |
1 files changed, 487 insertions, 464 deletions
diff --git a/fs/nfs/write.c b/fs/nfs/write.c index ac1dc331ba3..5e2f1030454 100644 --- a/fs/nfs/write.c +++ b/fs/nfs/write.c @@ -42,10 +42,11 @@ * Local function declarations */ static void nfs_redirty_request(struct nfs_page *req); -static const struct rpc_call_ops nfs_write_common_ops; static const struct rpc_call_ops nfs_commit_ops; static const struct nfs_pgio_completion_ops nfs_async_write_completion_ops; static const struct nfs_commit_completion_ops nfs_commit_completion_ops; +static const struct nfs_rw_ops nfs_rw_write_ops; +static void nfs_clear_request_commit(struct nfs_page *req); static struct kmem_cache *nfs_wdata_cachep; static mempool_t *nfs_wdata_mempool; @@ -70,76 +71,19 @@ void nfs_commit_free(struct nfs_commit_data *p) } EXPORT_SYMBOL_GPL(nfs_commit_free); -struct nfs_write_header *nfs_writehdr_alloc(void) +static struct nfs_rw_header *nfs_writehdr_alloc(void) { - struct nfs_write_header *p = mempool_alloc(nfs_wdata_mempool, GFP_NOIO); - - if (p) { - struct nfs_pgio_header *hdr = &p->header; + struct nfs_rw_header *p = mempool_alloc(nfs_wdata_mempool, GFP_NOIO); + if (p) memset(p, 0, sizeof(*p)); - INIT_LIST_HEAD(&hdr->pages); - INIT_LIST_HEAD(&hdr->rpc_list); - spin_lock_init(&hdr->lock); - atomic_set(&hdr->refcnt, 0); - hdr->verf = &p->verf; - } return p; } -EXPORT_SYMBOL_GPL(nfs_writehdr_alloc); -static struct nfs_write_data *nfs_writedata_alloc(struct nfs_pgio_header *hdr, - unsigned int pagecount) +static void nfs_writehdr_free(struct nfs_rw_header *whdr) { - struct nfs_write_data *data, *prealloc; - - prealloc = &container_of(hdr, struct nfs_write_header, header)->rpc_data; - if (prealloc->header == NULL) - data = prealloc; - else - data = kzalloc(sizeof(*data), GFP_KERNEL); - if (!data) - goto out; - - if (nfs_pgarray_set(&data->pages, pagecount)) { - data->header = hdr; - atomic_inc(&hdr->refcnt); - } else { - if (data != prealloc) - kfree(data); - data = NULL; - } -out: - return data; -} - -void nfs_writehdr_free(struct nfs_pgio_header *hdr) -{ - struct nfs_write_header *whdr = container_of(hdr, struct nfs_write_header, header); mempool_free(whdr, nfs_wdata_mempool); } -EXPORT_SYMBOL_GPL(nfs_writehdr_free); - -void nfs_writedata_release(struct nfs_write_data *wdata) -{ - struct nfs_pgio_header *hdr = wdata->header; - struct nfs_write_header *write_header = container_of(hdr, struct nfs_write_header, header); - - put_nfs_open_context(wdata->args.context); - if (wdata->pages.pagevec != wdata->pages.page_array) - kfree(wdata->pages.pagevec); - if (wdata == &write_header->rpc_data) { - wdata->header = NULL; - wdata = NULL; - } - if (atomic_dec_and_test(&hdr->refcnt)) - hdr->completion_ops->completion(hdr); - /* Note: we only free the rpc_task after callbacks are done. - * See the comment in rpc_free_task() for why - */ - kfree(wdata); -} -EXPORT_SYMBOL_GPL(nfs_writedata_release); static void nfs_context_set_write_error(struct nfs_open_context *ctx, int error) { @@ -148,8 +92,15 @@ static void nfs_context_set_write_error(struct nfs_open_context *ctx, int error) set_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags); } +/* + * nfs_page_find_head_request_locked - find head request associated with @page + * + * must be called while holding the inode lock. + * + * returns matching head request with reference held, or NULL if not found. + */ static struct nfs_page * -nfs_page_find_request_locked(struct nfs_inode *nfsi, struct page *page) +nfs_page_find_head_request_locked(struct nfs_inode *nfsi, struct page *page) { struct nfs_page *req = NULL; @@ -161,25 +112,33 @@ nfs_page_find_request_locked(struct nfs_inode *nfsi, struct page *page) /* Linearly search the commit list for the correct req */ list_for_each_entry_safe(freq, t, &nfsi->commit_info.list, wb_list) { if (freq->wb_page == page) { - req = freq; + req = freq->wb_head; break; } } } - if (req) + if (req) { + WARN_ON_ONCE(req->wb_head != req); + kref_get(&req->wb_kref); + } return req; } -static struct nfs_page *nfs_page_find_request(struct page *page) +/* + * nfs_page_find_head_request - find head request associated with @page + * + * returns matching head request with reference held, or NULL if not found. + */ +static struct nfs_page *nfs_page_find_head_request(struct page *page) { struct inode *inode = page_file_mapping(page)->host; struct nfs_page *req = NULL; spin_lock(&inode->i_lock); - req = nfs_page_find_request_locked(NFS_I(inode), page); + req = nfs_page_find_head_request_locked(NFS_I(inode), page); spin_unlock(&inode->i_lock); return req; } @@ -211,18 +170,78 @@ static void nfs_set_pageerror(struct page *page) nfs_zap_mapping(page_file_mapping(page)->host, page_file_mapping(page)); } +/* + * nfs_page_group_search_locked + * @head - head request of page group + * @page_offset - offset into page + * + * Search page group with head @head to find a request that contains the + * page offset @page_offset. + * + * Returns a pointer to the first matching nfs request, or NULL if no + * match is found. + * + * Must be called with the page group lock held + */ +static struct nfs_page * +nfs_page_group_search_locked(struct nfs_page *head, unsigned int page_offset) +{ + struct nfs_page *req; + + WARN_ON_ONCE(head != head->wb_head); + WARN_ON_ONCE(!test_bit(PG_HEADLOCK, &head->wb_head->wb_flags)); + + req = head; + do { + if (page_offset >= req->wb_pgbase && + page_offset < (req->wb_pgbase + req->wb_bytes)) + return req; + + req = req->wb_this_page; + } while (req != head); + + return NULL; +} + +/* + * nfs_page_group_covers_page + * @head - head request of page group + * + * Return true if the page group with head @head covers the whole page, + * returns false otherwise + */ +static bool nfs_page_group_covers_page(struct nfs_page *req) +{ + struct nfs_page *tmp; + unsigned int pos = 0; + unsigned int len = nfs_page_length(req->wb_page); + + nfs_page_group_lock(req); + + do { + tmp = nfs_page_group_search_locked(req->wb_head, pos); + if (tmp) { + /* no way this should happen */ + WARN_ON_ONCE(tmp->wb_pgbase != pos); + pos += tmp->wb_bytes - (pos - tmp->wb_pgbase); + } + } while (tmp && pos < len); + + nfs_page_group_unlock(req); + WARN_ON_ONCE(pos > len); + return pos == len; +} + /* We can set the PG_uptodate flag if we see that a write request * covers the full page. */ -static void nfs_mark_uptodate(struct page *page, unsigned int base, unsigned int count) +static void nfs_mark_uptodate(struct nfs_page *req) { - if (PageUptodate(page)) - return; - if (base != 0) + if (PageUptodate(req->wb_page)) return; - if (count != nfs_page_length(page)) + if (!nfs_page_group_covers_page(req)) return; - SetPageUptodate(page); + SetPageUptodate(req->wb_page); } static int wb_priority(struct writeback_control *wbc) @@ -258,46 +277,259 @@ static void nfs_set_page_writeback(struct page *page) } } -static void nfs_end_page_writeback(struct page *page) +static void nfs_end_page_writeback(struct nfs_page *req) { - struct inode *inode = page_file_mapping(page)->host; + struct inode *inode = page_file_mapping(req->wb_page)->host; struct nfs_server *nfss = NFS_SERVER(inode); - end_page_writeback(page); + if (!nfs_page_group_sync_on_bit(req, PG_WB_END)) + return; + + end_page_writeback(req->wb_page); if (atomic_long_dec_return(&nfss->writeback) < NFS_CONGESTION_OFF_THRESH) clear_bdi_congested(&nfss->backing_dev_info, BLK_RW_ASYNC); } -static struct nfs_page *nfs_find_and_lock_request(struct page *page, bool nonblock) + +/* nfs_page_group_clear_bits + * @req - an nfs request + * clears all page group related bits from @req + */ +static void +nfs_page_group_clear_bits(struct nfs_page *req) +{ + clear_bit(PG_TEARDOWN, &req->wb_flags); + clear_bit(PG_UNLOCKPAGE, &req->wb_flags); + clear_bit(PG_UPTODATE, &req->wb_flags); + clear_bit(PG_WB_END, &req->wb_flags); + clear_bit(PG_REMOVE, &req->wb_flags); +} + + +/* + * nfs_unroll_locks_and_wait - unlock all newly locked reqs and wait on @req + * + * this is a helper function for nfs_lock_and_join_requests + * + * @inode - inode associated with request page group, must be holding inode lock + * @head - head request of page group, must be holding head lock + * @req - request that couldn't lock and needs to wait on the req bit lock + * @nonblock - if true, don't actually wait + * + * NOTE: this must be called holding page_group bit lock and inode spin lock + * and BOTH will be released before returning. + * + * returns 0 on success, < 0 on error. + */ +static int +nfs_unroll_locks_and_wait(struct inode *inode, struct nfs_page *head, + struct nfs_page *req, bool nonblock) + __releases(&inode->i_lock) +{ + struct nfs_page *tmp; + int ret; + + /* relinquish all the locks successfully grabbed this run */ + for (tmp = head ; tmp != req; tmp = tmp->wb_this_page) + nfs_unlock_request(tmp); + + WARN_ON_ONCE(test_bit(PG_TEARDOWN, &req->wb_flags)); + + /* grab a ref on the request that will be waited on */ + kref_get(&req->wb_kref); + + nfs_page_group_unlock(head); + spin_unlock(&inode->i_lock); + + /* release ref from nfs_page_find_head_request_locked */ + nfs_release_request(head); + + if (!nonblock) + ret = nfs_wait_on_request(req); + else + ret = -EAGAIN; + nfs_release_request(req); + + return ret; +} + +/* + * nfs_destroy_unlinked_subrequests - destroy recently unlinked subrequests + * + * @destroy_list - request list (using wb_this_page) terminated by @old_head + * @old_head - the old head of the list + * + * All subrequests must be locked and removed from all lists, so at this point + * they are only "active" in this function, and possibly in nfs_wait_on_request + * with a reference held by some other context. + */ +static void +nfs_destroy_unlinked_subrequests(struct nfs_page *destroy_list, + struct nfs_page *old_head) +{ + while (destroy_list) { + struct nfs_page *subreq = destroy_list; + + destroy_list = (subreq->wb_this_page == old_head) ? + NULL : subreq->wb_this_page; + + WARN_ON_ONCE(old_head != subreq->wb_head); + + /* make sure old group is not used */ + subreq->wb_head = subreq; + subreq->wb_this_page = subreq; + + nfs_clear_request_commit(subreq); + + /* subreq is now totally disconnected from page group or any + * write / commit lists. last chance to wake any waiters */ + nfs_unlock_request(subreq); + + if (!test_bit(PG_TEARDOWN, &subreq->wb_flags)) { + /* release ref on old head request */ + nfs_release_request(old_head); + + nfs_page_group_clear_bits(subreq); + + /* release the PG_INODE_REF reference */ + if (test_and_clear_bit(PG_INODE_REF, &subreq->wb_flags)) + nfs_release_request(subreq); + else + WARN_ON_ONCE(1); + } else { + WARN_ON_ONCE(test_bit(PG_CLEAN, &subreq->wb_flags)); + /* zombie requests have already released the last + * reference and were waiting on the rest of the + * group to complete. Since it's no longer part of a + * group, simply free the request */ + nfs_page_group_clear_bits(subreq); + nfs_free_request(subreq); + } + } +} + +/* + * nfs_lock_and_join_requests - join all subreqs to the head req and return + * a locked reference, cancelling any pending + * operations for this page. + * + * @page - the page used to lookup the "page group" of nfs_page structures + * @nonblock - if true, don't block waiting for request locks + * + * 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, bool nonblock) { struct inode *inode = page_file_mapping(page)->host; - struct nfs_page *req; + struct nfs_page *head, *subreq; + struct nfs_page *destroy_list = NULL; + unsigned int total_bytes; int ret; +try_again: + total_bytes = 0; + + WARN_ON_ONCE(destroy_list); + spin_lock(&inode->i_lock); - for (;;) { - req = nfs_page_find_request_locked(NFS_I(inode), page); - if (req == NULL) - break; - if (nfs_lock_request(req)) - break; - /* Note: If we hold the page lock, as is the case in nfs_writepage, - * then the call to nfs_lock_request() will always - * succeed provided that someone hasn't already marked the - * request as dirty (in which case we don't care). - */ + + /* + * 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_page_find_head_request_locked(NFS_I(inode), page); + + if (!head) { spin_unlock(&inode->i_lock); - if (!nonblock) - ret = nfs_wait_on_request(req); - else - ret = -EAGAIN; - nfs_release_request(req); - if (ret != 0) + return NULL; + } + + /* lock each request in the page group */ + nfs_page_group_lock(head); + subreq = head; + do { + /* + * Subrequests are always contiguous, non overlapping + * and in order. If not, it's a programming error. + */ + WARN_ON_ONCE(subreq->wb_offset != + (head->wb_offset + total_bytes)); + + /* keep track of how many bytes this group covers */ + total_bytes += subreq->wb_bytes; + + if (!nfs_lock_request(subreq)) { + /* releases page group bit lock and + * inode spin lock and all references */ + ret = nfs_unroll_locks_and_wait(inode, head, + subreq, nonblock); + + if (ret == 0) + goto try_again; + return ERR_PTR(ret); - spin_lock(&inode->i_lock); + } + + subreq = subreq->wb_this_page; + } while (subreq != head); + + /* 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_list_remove_request(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; + + /* change head request to cover whole range that + * the former page group covered */ + head->wb_bytes = total_bytes; } + + /* + * prepare head request to be added to new pgio descriptor + */ + nfs_page_group_clear_bits(head); + + /* + * some part of the group was still on the inode list - otherwise + * the group wouldn't be involved in async write. + * grab a reference for the head request, iff it needs one. + */ + if (!test_and_set_bit(PG_INODE_REF, &head->wb_flags)) + kref_get(&head->wb_kref); + + nfs_page_group_unlock(head); + + /* drop lock to clear_request_commit the head req and clean up + * requests on destroy list */ spin_unlock(&inode->i_lock); - return req; + + nfs_destroy_unlinked_subrequests(destroy_list, head); + + /* clean up commit list state */ + nfs_clear_request_commit(head); + + /* still holds ref on head from nfs_page_find_head_request_locked + * and still has lock on head from lock loop */ + return head; } /* @@ -310,7 +542,7 @@ static int nfs_page_async_flush(struct nfs_pageio_descriptor *pgio, struct nfs_page *req; int ret = 0; - req = nfs_find_and_lock_request(page, nonblock); + req = nfs_lock_and_join_requests(page, nonblock); if (!req) goto out; ret = PTR_ERR(req); @@ -354,10 +586,8 @@ static int nfs_writepage_locked(struct page *page, struct writeback_control *wbc struct nfs_pageio_descriptor pgio; int err; - NFS_PROTO(page_file_mapping(page)->host)->write_pageio_init(&pgio, - page->mapping->host, - wb_priority(wbc), - &nfs_async_write_completion_ops); + nfs_pageio_init_write(&pgio, page->mapping->host, wb_priority(wbc), + false, &nfs_async_write_completion_ops); err = nfs_do_writepage(page, wbc, &pgio); nfs_pageio_complete(&pgio); if (err < 0) @@ -400,12 +630,13 @@ int nfs_writepages(struct address_space *mapping, struct writeback_control *wbc) nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGES); - NFS_PROTO(inode)->write_pageio_init(&pgio, inode, wb_priority(wbc), &nfs_async_write_completion_ops); + nfs_pageio_init_write(&pgio, inode, wb_priority(wbc), false, + &nfs_async_write_completion_ops); err = write_cache_pages(mapping, wbc, nfs_writepages_callback, &pgio); nfs_pageio_complete(&pgio); clear_bit_unlock(NFS_INO_FLUSHING, bitlock); - smp_mb__after_clear_bit(); + smp_mb__after_atomic(); wake_up_bit(bitlock, NFS_INO_FLUSHING); if (err < 0) @@ -425,6 +656,8 @@ static void nfs_inode_add_request(struct inode *inode, struct nfs_page *req) { struct nfs_inode *nfsi = NFS_I(inode); + WARN_ON_ONCE(req->wb_this_page != req); + /* Lock the request! */ nfs_lock_request(req); @@ -441,6 +674,9 @@ static void nfs_inode_add_request(struct inode *inode, struct nfs_page *req) set_page_private(req->wb_page, (unsigned long)req); } nfsi->npages++; + /* this a head request for a page group - mark it as having an + * extra reference so sub groups can follow suit */ + WARN_ON(test_and_set_bit(PG_INODE_REF, &req->wb_flags)); kref_get(&req->wb_kref); spin_unlock(&inode->i_lock); } @@ -452,16 +688,23 @@ static void nfs_inode_remove_request(struct nfs_page *req) { struct inode *inode = req->wb_context->dentry->d_inode; struct nfs_inode *nfsi = NFS_I(inode); + struct nfs_page *head; - spin_lock(&inode->i_lock); - if (likely(!PageSwapCache(req->wb_page))) { - set_page_private(req->wb_page, 0); - ClearPagePrivate(req->wb_page); - clear_bit(PG_MAPPED, &req->wb_flags); + if (nfs_page_group_sync_on_bit(req, PG_REMOVE)) { + head = req->wb_head; + + spin_lock(&inode->i_lock); + if (likely(!PageSwapCache(head->wb_page))) { + set_page_private(head->wb_page, 0); + ClearPagePrivate(head->wb_page); + clear_bit(PG_MAPPED, &head->wb_flags); + } + nfsi->npages--; + spin_unlock(&inode->i_lock); } - nfsi->npages--; - spin_unlock(&inode->i_lock); - nfs_release_request(req); + + if (test_and_clear_bit(PG_INODE_REF, &req->wb_flags)) + nfs_release_request(req); } static void @@ -583,7 +826,7 @@ nfs_clear_request_commit(struct nfs_page *req) } static inline -int nfs_write_need_commit(struct nfs_write_data *data) +int nfs_write_need_commit(struct nfs_pgio_data *data) { if (data->verf.committed == NFS_DATA_SYNC) return data->header->lseg == NULL; @@ -614,7 +857,7 @@ nfs_clear_request_commit(struct nfs_page *req) } static inline -int nfs_write_need_commit(struct nfs_write_data *data) +int nfs_write_need_commit(struct nfs_pgio_data *data) { return 0; } @@ -645,7 +888,7 @@ static void nfs_write_completion(struct nfs_pgio_header *hdr) goto next; } if (test_bit(NFS_IOHDR_NEED_COMMIT, &hdr->flags)) { - memcpy(&req->wb_verf, &hdr->verf->verifier, sizeof(req->wb_verf)); + memcpy(&req->wb_verf, &hdr->verf.verifier, sizeof(req->wb_verf)); nfs_mark_request_commit(req, hdr->lseg, &cinfo); goto next; } @@ -653,7 +896,7 @@ remove_req: nfs_inode_remove_request(req); next: nfs_unlock_request(req); - nfs_end_page_writeback(req->wb_page); + nfs_end_page_writeback(req); nfs_release_request(req); } out: @@ -661,7 +904,7 @@ out: } #if IS_ENABLED(CONFIG_NFS_V3) || IS_ENABLED(CONFIG_NFS_V4) -static unsigned long +unsigned long nfs_reqs_to_commit(struct nfs_commit_info *cinfo) { return cinfo->mds->ncommit; @@ -718,7 +961,7 @@ nfs_scan_commit(struct inode *inode, struct list_head *dst, } #else -static unsigned long nfs_reqs_to_commit(struct nfs_commit_info *cinfo) +unsigned long nfs_reqs_to_commit(struct nfs_commit_info *cinfo) { return 0; } @@ -754,10 +997,14 @@ static struct nfs_page *nfs_try_to_update_request(struct inode *inode, spin_lock(&inode->i_lock); for (;;) { - req = nfs_page_find_request_locked(NFS_I(inode), page); + req = nfs_page_find_head_request_locked(NFS_I(inode), page); if (req == NULL) goto out_unlock; + /* should be handled by nfs_flush_incompatible */ + WARN_ON_ONCE(req->wb_head != req); + WARN_ON_ONCE(req->wb_this_page != req); + rqend = req->wb_offset + req->wb_bytes; /* * Tell the caller to flush out the request if @@ -819,7 +1066,7 @@ static struct nfs_page * nfs_setup_write_request(struct nfs_open_context* ctx, req = nfs_try_to_update_request(inode, page, offset, bytes); if (req != NULL) goto out; - req = nfs_create_request(ctx, inode, page, offset, bytes); + req = nfs_create_request(ctx, page, NULL, offset, bytes); if (IS_ERR(req)) goto out; nfs_inode_add_request(inode, req); @@ -837,7 +1084,7 @@ static int nfs_writepage_setup(struct nfs_open_context *ctx, struct page *page, return PTR_ERR(req); /* Update file length */ nfs_grow_file(page, offset, count); - nfs_mark_uptodate(page, req->wb_pgbase, req->wb_bytes); + nfs_mark_uptodate(req); nfs_mark_request_dirty(req); nfs_unlock_and_release_request(req); return 0; @@ -858,11 +1105,13 @@ int nfs_flush_incompatible(struct file *file, struct page *page) * dropped page. */ do { - req = nfs_page_find_request(page); + req = nfs_page_find_head_request(page); if (req == NULL) return 0; l_ctx = req->wb_lock_context; do_flush = req->wb_page != page || req->wb_context != ctx; + /* for now, flush if more than 1 request in page_group */ + do_flush |= req->wb_this_page != req; if (l_ctx && ctx->dentry->d_inode->i_flock != NULL) { do_flush |= l_ctx->lockowner.l_owner != current->files || l_ctx->lockowner.l_pid != current->tgid; @@ -909,11 +1158,18 @@ bool nfs_ctx_key_to_expire(struct nfs_open_context *ctx) */ 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 (NFS_I(inode)->cache_validity & (NFS_INO_INVALID_DATA|NFS_INO_REVAL_PAGECACHE)) + 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; } @@ -922,19 +1178,20 @@ out: * extend the write to cover the entire page in order to avoid fragmentation * inefficiencies. * - * If the file is opened for synchronous writes or if we have a write delegation - * from the server then we can just skip the rest of the checks. + * 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) { 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 (nfs_write_pageuptodate(page, inode) && (inode->i_flock == NULL || - (inode->i_flock->fl_start == 0 && + if (inode->i_flock == NULL || (inode->i_flock->fl_start == 0 && inode->i_flock->fl_end == OFFSET_MAX && - inode->i_flock->fl_type != F_RDLCK))) + inode->i_flock->fl_type != F_RDLCK)) return 1; return 0; } @@ -954,10 +1211,8 @@ int nfs_updatepage(struct file *file, struct page *page, nfs_inc_stats(inode, NFSIOS_VFSUPDATEPAGE); - dprintk("NFS: nfs_updatepage(%s/%s %d@%lld)\n", - file->f_path.dentry->d_parent->d_name.name, - file->f_path.dentry->d_name.name, count, - (long long)(page_file_offset(page) + offset)); + dprintk("NFS: nfs_updatepage(%pD2 %d@%lld)\n", + file, count, (long long)(page_file_offset(page) + offset)); if (nfs_can_extend_write(file, page, inode)) { count = max(count + offset, nfs_page_length(page)); @@ -986,126 +1241,17 @@ static int flush_task_priority(int how) return RPC_PRIORITY_NORMAL; } -int nfs_initiate_write(struct rpc_clnt *clnt, - struct nfs_write_data *data, - const struct rpc_call_ops *call_ops, - int how, int flags) +static void nfs_initiate_write(struct nfs_pgio_data *data, struct rpc_message *msg, + struct rpc_task_setup *task_setup_data, int how) { struct inode *inode = data->header->inode; int priority = flush_task_priority(how); - struct rpc_task *task; - struct rpc_message msg = { - .rpc_argp = &data->args, - .rpc_resp = &data->res, - .rpc_cred = data->header->cred, - }; - struct rpc_task_setup task_setup_data = { - .rpc_client = clnt, - .task = &data->task, - .rpc_message = &msg, - .callback_ops = call_ops, - .callback_data = data, - .workqueue = nfsiod_workqueue, - .flags = RPC_TASK_ASYNC | flags, - .priority = priority, - }; - int ret = 0; - - /* Set up the initial task struct. */ - NFS_PROTO(inode)->write_setup(data, &msg); - dprintk("NFS: %5u initiated write call " - "(req %s/%lld, %u bytes @ offset %llu)\n", - data->task.tk_pid, - inode->i_sb->s_id, - (long long)NFS_FILEID(inode), - data->args.count, - (unsigned long long)data->args.offset); + task_setup_data->priority = priority; + NFS_PROTO(inode)->write_setup(data, msg); nfs4_state_protect_write(NFS_SERVER(inode)->nfs_client, - &task_setup_data.rpc_client, &msg, data); - - task = rpc_run_task(&task_setup_data); - if (IS_ERR(task)) { - ret = PTR_ERR(task); - goto out; - } - if (how & FLUSH_SYNC) { - ret = rpc_wait_for_completion_task(task); - if (ret == 0) - ret = task->tk_status; - } - rpc_put_task(task); -out: - return ret; -} -EXPORT_SYMBOL_GPL(nfs_initiate_write); - -/* - * Set up the argument/result storage required for the RPC call. - */ -static void nfs_write_rpcsetup(struct nfs_write_data *data, - unsigned int count, unsigned int offset, - int how, struct nfs_commit_info *cinfo) -{ - struct nfs_page *req = data->header->req; - - /* Set up the RPC argument and reply structs - * NB: take care not to mess about with data->commit et al. */ - - data->args.fh = NFS_FH(data->header->inode); - data->args.offset = req_offset(req) + offset; - /* pnfs_set_layoutcommit needs this */ - data->mds_offset = data->args.offset; - data->args.pgbase = req->wb_pgbase + offset; - data->args.pages = data->pages.pagevec; - data->args.count = count; - data->args.context = get_nfs_open_context(req->wb_context); - data->args.lock_context = req->wb_lock_context; - data->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; - default: - data->args.stable = NFS_FILE_SYNC; - } - - data->res.fattr = &data->fattr; - data->res.count = count; - data->res.verf = &data->verf; - nfs_fattr_init(&data->fattr); -} - -static int nfs_do_write(struct nfs_write_data *data, - const struct rpc_call_ops *call_ops, - int how) -{ - struct inode *inode = data->header->inode; - - return nfs_initiate_write(NFS_CLIENT(inode), data, call_ops, how, 0); -} - -static int nfs_do_multiple_writes(struct list_head *head, - const struct rpc_call_ops *call_ops, - int how) -{ - struct nfs_write_data *data; - int ret = 0; - - while (!list_empty(head)) { - int ret2; - - data = list_first_entry(head, struct nfs_write_data, list); - list_del_init(&data->list); - - ret2 = nfs_do_write(data, call_ops, how); - if (ret == 0) - ret = ret2; - } - return ret; + &task_setup_data->rpc_client, msg, data); } /* If a nfs_flush_* function fails, it should remove reqs from @head and @@ -1116,7 +1262,7 @@ static void nfs_redirty_request(struct nfs_page *req) { nfs_mark_request_dirty(req); nfs_unlock_request(req); - nfs_end_page_writeback(req->wb_page); + nfs_end_page_writeback(req); nfs_release_request(req); } @@ -1136,173 +1282,30 @@ static const struct nfs_pgio_completion_ops nfs_async_write_completion_ops = { .completion = nfs_write_completion, }; -static void nfs_flush_error(struct nfs_pageio_descriptor *desc, - struct nfs_pgio_header *hdr) -{ - set_bit(NFS_IOHDR_REDO, &hdr->flags); - while (!list_empty(&hdr->rpc_list)) { - struct nfs_write_data *data = list_first_entry(&hdr->rpc_list, - struct nfs_write_data, list); - list_del(&data->list); - nfs_writedata_release(data); - } - desc->pg_completion_ops->error_cleanup(&desc->pg_list); -} - -/* - * Generate multiple small requests to write out a single - * contiguous dirty area on one page. - */ -static int nfs_flush_multi(struct nfs_pageio_descriptor *desc, - struct nfs_pgio_header *hdr) -{ - struct nfs_page *req = hdr->req; - struct page *page = req->wb_page; - struct nfs_write_data *data; - size_t wsize = desc->pg_bsize, nbytes; - unsigned int offset; - int requests = 0; - struct nfs_commit_info cinfo; - - nfs_init_cinfo(&cinfo, desc->pg_inode, desc->pg_dreq); - - if ((desc->pg_ioflags & FLUSH_COND_STABLE) && - (desc->pg_moreio || nfs_reqs_to_commit(&cinfo) || - desc->pg_count > wsize)) - desc->pg_ioflags &= ~FLUSH_COND_STABLE; - - - offset = 0; - nbytes = desc->pg_count; - do { - size_t len = min(nbytes, wsize); - - data = nfs_writedata_alloc(hdr, 1); - if (!data) { - nfs_flush_error(desc, hdr); - return -ENOMEM; - } - data->pages.pagevec[0] = page; - nfs_write_rpcsetup(data, len, offset, desc->pg_ioflags, &cinfo); - list_add(&data->list, &hdr->rpc_list); - requests++; - nbytes -= len; - offset += len; - } while (nbytes != 0); - nfs_list_remove_request(req); - nfs_list_add_request(req, &hdr->pages); - desc->pg_rpc_callops = &nfs_write_common_ops; - return 0; -} - -/* - * Create an RPC task for the given 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. - */ -static int nfs_flush_one(struct nfs_pageio_descriptor *desc, - struct nfs_pgio_header *hdr) -{ - struct nfs_page *req; - struct page **pages; - struct nfs_write_data *data; - struct list_head *head = &desc->pg_list; - struct nfs_commit_info cinfo; - - data = nfs_writedata_alloc(hdr, nfs_page_array_len(desc->pg_base, - desc->pg_count)); - if (!data) { - nfs_flush_error(desc, hdr); - return -ENOMEM; - } - - nfs_init_cinfo(&cinfo, desc->pg_inode, desc->pg_dreq); - pages = data->pages.pagevec; - while (!list_empty(head)) { - req = nfs_list_entry(head->next); - nfs_list_remove_request(req); - nfs_list_add_request(req, &hdr->pages); - *pages++ = req->wb_page; - } - - 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_write_rpcsetup(data, desc->pg_count, 0, desc->pg_ioflags, &cinfo); - list_add(&data->list, &hdr->rpc_list); - desc->pg_rpc_callops = &nfs_write_common_ops; - return 0; -} - -int nfs_generic_flush(struct nfs_pageio_descriptor *desc, - struct nfs_pgio_header *hdr) -{ - if (desc->pg_bsize < PAGE_CACHE_SIZE) - return nfs_flush_multi(desc, hdr); - return nfs_flush_one(desc, hdr); -} -EXPORT_SYMBOL_GPL(nfs_generic_flush); - -static int nfs_generic_pg_writepages(struct nfs_pageio_descriptor *desc) -{ - struct nfs_write_header *whdr; - struct nfs_pgio_header *hdr; - int ret; - - whdr = nfs_writehdr_alloc(); - if (!whdr) { - desc->pg_completion_ops->error_cleanup(&desc->pg_list); - return -ENOMEM; - } - hdr = &whdr->header; - nfs_pgheader_init(desc, hdr, nfs_writehdr_free); - atomic_inc(&hdr->refcnt); - ret = nfs_generic_flush(desc, hdr); - if (ret == 0) - ret = nfs_do_multiple_writes(&hdr->rpc_list, - desc->pg_rpc_callops, - desc->pg_ioflags); - if (atomic_dec_and_test(&hdr->refcnt)) - hdr->completion_ops->completion(hdr); - return ret; -} - -static const struct nfs_pageio_ops nfs_pageio_write_ops = { - .pg_test = nfs_generic_pg_test, - .pg_doio = nfs_generic_pg_writepages, -}; - void nfs_pageio_init_write(struct nfs_pageio_descriptor *pgio, - struct inode *inode, int ioflags, + struct inode *inode, int ioflags, bool force_mds, const struct nfs_pgio_completion_ops *compl_ops) { - nfs_pageio_init(pgio, inode, &nfs_pageio_write_ops, compl_ops, - NFS_SERVER(inode)->wsize, ioflags); + 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) { - pgio->pg_ops = &nfs_pageio_write_ops; + pgio->pg_ops = &nfs_pgio_rw_ops; pgio->pg_bsize = NFS_SERVER(pgio->pg_inode)->wsize; } EXPORT_SYMBOL_GPL(nfs_pageio_reset_write_mds); -void nfs_write_prepare(struct rpc_task *task, void *calldata) -{ - struct nfs_write_data *data = calldata; - int err; - err = NFS_PROTO(data->header->inode)->write_rpc_prepare(task, data); - if (err) - rpc_exit(task, err); -} - void nfs_commit_prepare(struct rpc_task *task, void *calldata) { struct nfs_commit_data *data = calldata; @@ -1310,23 +1313,8 @@ void nfs_commit_prepare(struct rpc_task *task, void *calldata) NFS_PROTO(data->inode)->commit_rpc_prepare(task, data); } -/* - * Handle a write reply that flushes a whole page. - * - * FIXME: There is an inherent race with invalidate_inode_pages and - * writebacks since the page->count is kept > 1 for as long - * as the page has a write request pending. - */ -static void nfs_writeback_done_common(struct rpc_task *task, void *calldata) -{ - struct nfs_write_data *data = calldata; - - nfs_writeback_done(task, data); -} - -static void nfs_writeback_release_common(void *calldata) +static void nfs_writeback_release_common(struct nfs_pgio_data *data) { - struct nfs_write_data *data = calldata; struct nfs_pgio_header *hdr = data->header; int status = data->task.tk_status; @@ -1335,34 +1323,46 @@ static void nfs_writeback_release_common(void *calldata) if (test_bit(NFS_IOHDR_NEED_RESCHED, &hdr->flags)) ; /* Do nothing */ else if (!test_and_set_bit(NFS_IOHDR_NEED_COMMIT, &hdr->flags)) - memcpy(hdr->verf, &data->verf, sizeof(*hdr->verf)); - else if (memcmp(hdr->verf, &data->verf, sizeof(*hdr->verf))) + memcpy(&hdr->verf, &data->verf, sizeof(hdr->verf)); + else if (memcmp(&hdr->verf, &data->verf, sizeof(hdr->verf))) set_bit(NFS_IOHDR_NEED_RESCHED, &hdr->flags); spin_unlock(&hdr->lock); } - nfs_writedata_release(data); } -static const struct rpc_call_ops nfs_write_common_ops = { - .rpc_call_prepare = nfs_write_prepare, - .rpc_call_done = nfs_writeback_done_common, - .rpc_release = nfs_writeback_release_common, -}; +/* + * 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; +} /* * This function is called when the WRITE call is complete. */ -void nfs_writeback_done(struct rpc_task *task, struct nfs_write_data *data) +static int nfs_writeback_done(struct rpc_task *task, struct nfs_pgio_data *data, + struct inode *inode) { - struct nfs_writeargs *argp = &data->args; - struct nfs_writeres *resp = &data->res; - struct inode *inode = data->header->inode; int status; - dprintk("NFS: %5u nfs_writeback_done (status %d)\n", - task->tk_pid, task->tk_status); - /* * ->write_done will attempt to use post-op attributes to detect * conflicting writes by other clients. A strict interpretation @@ -1372,11 +1372,11 @@ void nfs_writeback_done(struct rpc_task *task, struct nfs_write_data *data) */ status = NFS_PROTO(inode)->write_done(task, data); if (status != 0) - return; - nfs_add_stats(inode, NFSIOS_SERVERWRITTENBYTES, resp->count); + return status; + nfs_add_stats(inode, NFSIOS_SERVERWRITTENBYTES, data->res.count); #if IS_ENABLED(CONFIG_NFS_V3) || IS_ENABLED(CONFIG_NFS_V4) - if (resp->verf->committed < argp->stable && task->tk_status >= 0) { + if (data->res.verf->committed < data->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. @@ -1392,18 +1392,31 @@ void nfs_writeback_done(struct rpc_task *task, struct nfs_write_data *data) dprintk("NFS: faulty NFS server %s:" " (committed = %d) != (stable = %d)\n", NFS_SERVER(inode)->nfs_client->cl_hostname, - resp->verf->committed, argp->stable); + data->res.verf->committed, data->args.stable); complain = jiffies + 300 * HZ; } } #endif - if (task->tk_status < 0) - nfs_set_pgio_error(data->header, task->tk_status, argp->offset); - else if (resp->count < argp->count) { + + /* Deal with the suid/sgid bit corner case */ + if (nfs_should_remove_suid(inode)) + nfs_mark_for_revalidate(inode); + return 0; +} + +/* + * This function is called when the WRITE call is complete. + */ +static void nfs_writeback_result(struct rpc_task *task, struct nfs_pgio_data *data) +{ + struct nfs_pgio_args *argp = &data->args; + struct nfs_pgio_res *resp = &data->res; + + if (resp->count < argp->count) { static unsigned long complain; /* This a short write! */ - nfs_inc_stats(inode, NFSIOS_SHORTWRITE); + nfs_inc_stats(data->header->inode, NFSIOS_SHORTWRITE); /* Has the server at least made some progress? */ if (resp->count == 0) { @@ -1454,7 +1467,7 @@ static int nfs_commit_set_lock(struct nfs_inode *nfsi, int may_wait) static void nfs_commit_clear_lock(struct nfs_inode *nfsi) { clear_bit(NFS_INO_COMMIT, &nfsi->flags); - smp_mb__after_clear_bit(); + smp_mb__after_atomic(); wake_up_bit(&nfsi->flags, NFS_INO_COMMIT); } @@ -1608,9 +1621,9 @@ static void nfs_commit_release_pages(struct nfs_commit_data *data) nfs_list_remove_request(req); nfs_clear_page_commit(req->wb_page); - dprintk("NFS: commit (%s/%lld %d@%lld)", + dprintk("NFS: commit (%s/%llu %d@%lld)", req->wb_context->dentry->d_sb->s_id, - (long long)NFS_FILEID(req->wb_context->dentry->d_inode), + (unsigned long long)NFS_FILEID(req->wb_context->dentry->d_inode), req->wb_bytes, (long long)req_offset(req)); if (status < 0) { @@ -1784,27 +1797,28 @@ int nfs_wb_page_cancel(struct inode *inode, struct page *page) struct nfs_page *req; int ret = 0; - for (;;) { - wait_on_page_writeback(page); - req = nfs_page_find_request(page); - if (req == NULL) - break; - if (nfs_lock_request(req)) { - nfs_clear_request_commit(req); - nfs_inode_remove_request(req); - /* - * In case nfs_inode_remove_request has marked the - * page as being dirty - */ - cancel_dirty_page(page, PAGE_CACHE_SIZE); - nfs_unlock_and_release_request(req); - break; - } - ret = nfs_wait_on_request(req); - nfs_release_request(req); - if (ret < 0) - break; + 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, false); + + 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); + /* + * In case nfs_inode_remove_request has marked the + * page as being dirty + */ + cancel_dirty_page(page, PAGE_CACHE_SIZE); + nfs_unlock_and_release_request(req); } + return ret; } @@ -1870,7 +1884,7 @@ int nfs_migrate_page(struct address_space *mapping, struct page *newpage, int __init nfs_init_writepagecache(void) { nfs_wdata_cachep = kmem_cache_create("nfs_write_data", - sizeof(struct nfs_write_header), + sizeof(struct nfs_rw_header), 0, SLAB_HWCACHE_ALIGN, NULL); if (nfs_wdata_cachep == NULL) @@ -1932,3 +1946,12 @@ void nfs_destroy_writepagecache(void) kmem_cache_destroy(nfs_wdata_cachep); } +static const struct nfs_rw_ops nfs_rw_write_ops = { + .rw_mode = FMODE_WRITE, + .rw_alloc_header = nfs_writehdr_alloc, + .rw_free_header = nfs_writehdr_free, + .rw_release = nfs_writeback_release_common, + .rw_done = nfs_writeback_done, + .rw_result = nfs_writeback_result, + .rw_initiate = nfs_initiate_write, +}; |