diff options
Diffstat (limited to 'ANDROID_3.4.5/fs/nfs/write.c')
-rw-r--r-- | ANDROID_3.4.5/fs/nfs/write.c | 1790 |
1 files changed, 0 insertions, 1790 deletions
diff --git a/ANDROID_3.4.5/fs/nfs/write.c b/ANDROID_3.4.5/fs/nfs/write.c deleted file mode 100644 index c0746232..00000000 --- a/ANDROID_3.4.5/fs/nfs/write.c +++ /dev/null @@ -1,1790 +0,0 @@ -/* - * linux/fs/nfs/write.c - * - * Write file data over NFS. - * - * Copyright (C) 1996, 1997, Olaf Kirch <okir@monad.swb.de> - */ - -#include <linux/types.h> -#include <linux/slab.h> -#include <linux/mm.h> -#include <linux/pagemap.h> -#include <linux/file.h> -#include <linux/writeback.h> -#include <linux/swap.h> -#include <linux/migrate.h> - -#include <linux/sunrpc/clnt.h> -#include <linux/nfs_fs.h> -#include <linux/nfs_mount.h> -#include <linux/nfs_page.h> -#include <linux/backing-dev.h> -#include <linux/export.h> - -#include <asm/uaccess.h> - -#include "delegation.h" -#include "internal.h" -#include "iostat.h" -#include "nfs4_fs.h" -#include "fscache.h" -#include "pnfs.h" - -#define NFSDBG_FACILITY NFSDBG_PAGECACHE - -#define MIN_POOL_WRITE (32) -#define MIN_POOL_COMMIT (4) - -/* - * Local function declarations - */ -static void nfs_pageio_init_write(struct nfs_pageio_descriptor *desc, - struct inode *inode, int ioflags); -static void nfs_redirty_request(struct nfs_page *req); -static const struct rpc_call_ops nfs_write_partial_ops; -static const struct rpc_call_ops nfs_write_full_ops; -static const struct rpc_call_ops nfs_commit_ops; - -static struct kmem_cache *nfs_wdata_cachep; -static mempool_t *nfs_wdata_mempool; -static mempool_t *nfs_commit_mempool; - -struct nfs_write_data *nfs_commitdata_alloc(void) -{ - struct nfs_write_data *p = mempool_alloc(nfs_commit_mempool, GFP_NOFS); - - if (p) { - memset(p, 0, sizeof(*p)); - INIT_LIST_HEAD(&p->pages); - } - return p; -} -EXPORT_SYMBOL_GPL(nfs_commitdata_alloc); - -void nfs_commit_free(struct nfs_write_data *p) -{ - if (p && (p->pagevec != &p->page_array[0])) - kfree(p->pagevec); - mempool_free(p, nfs_commit_mempool); -} -EXPORT_SYMBOL_GPL(nfs_commit_free); - -struct nfs_write_data *nfs_writedata_alloc(unsigned int pagecount) -{ - struct nfs_write_data *p = mempool_alloc(nfs_wdata_mempool, GFP_NOFS); - - if (p) { - memset(p, 0, sizeof(*p)); - INIT_LIST_HEAD(&p->pages); - p->npages = pagecount; - if (pagecount <= ARRAY_SIZE(p->page_array)) - p->pagevec = p->page_array; - else { - p->pagevec = kcalloc(pagecount, sizeof(struct page *), GFP_NOFS); - if (!p->pagevec) { - mempool_free(p, nfs_wdata_mempool); - p = NULL; - } - } - } - return p; -} - -void nfs_writedata_free(struct nfs_write_data *p) -{ - if (p && (p->pagevec != &p->page_array[0])) - kfree(p->pagevec); - mempool_free(p, nfs_wdata_mempool); -} - -void nfs_writedata_release(struct nfs_write_data *wdata) -{ - put_nfs_open_context(wdata->args.context); - nfs_writedata_free(wdata); -} - -static void nfs_context_set_write_error(struct nfs_open_context *ctx, int error) -{ - ctx->error = error; - smp_wmb(); - set_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags); -} - -static struct nfs_page *nfs_page_find_request_locked(struct page *page) -{ - struct nfs_page *req = NULL; - - if (PagePrivate(page)) { - req = (struct nfs_page *)page_private(page); - if (req != NULL) - kref_get(&req->wb_kref); - } - return req; -} - -static struct nfs_page *nfs_page_find_request(struct page *page) -{ - struct inode *inode = page->mapping->host; - struct nfs_page *req = NULL; - - spin_lock(&inode->i_lock); - req = nfs_page_find_request_locked(page); - spin_unlock(&inode->i_lock); - return req; -} - -/* Adjust the file length if we're writing beyond the end */ -static void nfs_grow_file(struct page *page, unsigned int offset, unsigned int count) -{ - struct inode *inode = page->mapping->host; - loff_t end, i_size; - pgoff_t end_index; - - spin_lock(&inode->i_lock); - i_size = i_size_read(inode); - end_index = (i_size - 1) >> PAGE_CACHE_SHIFT; - if (i_size > 0 && page->index < end_index) - goto out; - end = ((loff_t)page->index << PAGE_CACHE_SHIFT) + ((loff_t)offset+count); - if (i_size >= end) - goto out; - i_size_write(inode, end); - nfs_inc_stats(inode, NFSIOS_EXTENDWRITE); -out: - spin_unlock(&inode->i_lock); -} - -/* A writeback failed: mark the page as bad, and invalidate the page cache */ -static void nfs_set_pageerror(struct page *page) -{ - SetPageError(page); - nfs_zap_mapping(page->mapping->host, page->mapping); -} - -/* 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) -{ - if (PageUptodate(page)) - return; - if (base != 0) - return; - if (count != nfs_page_length(page)) - return; - SetPageUptodate(page); -} - -static int wb_priority(struct writeback_control *wbc) -{ - if (wbc->for_reclaim) - return FLUSH_HIGHPRI | FLUSH_STABLE; - if (wbc->for_kupdate || wbc->for_background) - return FLUSH_LOWPRI | FLUSH_COND_STABLE; - return FLUSH_COND_STABLE; -} - -/* - * NFS congestion control - */ - -int nfs_congestion_kb; - -#define NFS_CONGESTION_ON_THRESH (nfs_congestion_kb >> (PAGE_SHIFT-10)) -#define NFS_CONGESTION_OFF_THRESH \ - (NFS_CONGESTION_ON_THRESH - (NFS_CONGESTION_ON_THRESH >> 2)) - -static int nfs_set_page_writeback(struct page *page) -{ - int ret = test_set_page_writeback(page); - - if (!ret) { - struct inode *inode = page->mapping->host; - struct nfs_server *nfss = NFS_SERVER(inode); - - page_cache_get(page); - if (atomic_long_inc_return(&nfss->writeback) > - NFS_CONGESTION_ON_THRESH) { - set_bdi_congested(&nfss->backing_dev_info, - BLK_RW_ASYNC); - } - } - return ret; -} - -static void nfs_end_page_writeback(struct page *page) -{ - struct inode *inode = page->mapping->host; - struct nfs_server *nfss = NFS_SERVER(inode); - - end_page_writeback(page); - page_cache_release(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) -{ - struct inode *inode = page->mapping->host; - struct nfs_page *req; - int ret; - - spin_lock(&inode->i_lock); - for (;;) { - req = nfs_page_find_request_locked(page); - if (req == NULL) - break; - if (nfs_lock_request_dontget(req)) - break; - /* Note: If we hold the page lock, as is the case in nfs_writepage, - * then the call to nfs_lock_request_dontget() will always - * succeed provided that someone hasn't already marked the - * request as dirty (in which case we don't care). - */ - spin_unlock(&inode->i_lock); - if (!nonblock) - ret = nfs_wait_on_request(req); - else - ret = -EAGAIN; - nfs_release_request(req); - if (ret != 0) - return ERR_PTR(ret); - spin_lock(&inode->i_lock); - } - spin_unlock(&inode->i_lock); - return 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, bool nonblock) -{ - struct nfs_page *req; - int ret = 0; - - req = nfs_find_and_lock_request(page, nonblock); - if (!req) - goto out; - ret = PTR_ERR(req); - if (IS_ERR(req)) - goto out; - - ret = nfs_set_page_writeback(page); - BUG_ON(ret != 0); - BUG_ON(test_bit(PG_CLEAN, &req->wb_flags)); - - if (!nfs_pageio_add_request(pgio, req)) { - nfs_redirty_request(req); - ret = pgio->pg_error; - } -out: - return ret; -} - -static int nfs_do_writepage(struct page *page, struct writeback_control *wbc, struct nfs_pageio_descriptor *pgio) -{ - struct inode *inode = page->mapping->host; - int ret; - - nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGE); - nfs_add_stats(inode, NFSIOS_WRITEPAGES, 1); - - nfs_pageio_cond_complete(pgio, page->index); - ret = nfs_page_async_flush(pgio, page, wbc->sync_mode == WB_SYNC_NONE); - if (ret == -EAGAIN) { - redirty_page_for_writepage(wbc, page); - ret = 0; - } - 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; - int err; - - nfs_pageio_init_write(&pgio, page->mapping->host, wb_priority(wbc)); - err = nfs_do_writepage(page, wbc, &pgio); - nfs_pageio_complete(&pgio); - if (err < 0) - return err; - if (pgio.pg_error < 0) - return pgio.pg_error; - return 0; -} - -int nfs_writepage(struct page *page, struct writeback_control *wbc) -{ - int ret; - - ret = nfs_writepage_locked(page, wbc); - 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); - unlock_page(page); - return ret; -} - -int nfs_writepages(struct address_space *mapping, struct writeback_control *wbc) -{ - struct inode *inode = mapping->host; - unsigned long *bitlock = &NFS_I(inode)->flags; - struct nfs_pageio_descriptor pgio; - int err; - - /* Stop dirtying of new pages while we sync */ - err = wait_on_bit_lock(bitlock, NFS_INO_FLUSHING, - nfs_wait_bit_killable, TASK_KILLABLE); - if (err) - goto out_err; - - nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGES); - - nfs_pageio_init_write(&pgio, inode, wb_priority(wbc)); - 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(); - wake_up_bit(bitlock, NFS_INO_FLUSHING); - - if (err < 0) - goto out_err; - err = pgio.pg_error; - if (err < 0) - 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 nfs_inode *nfsi = NFS_I(inode); - - /* Lock the request! */ - nfs_lock_request_dontget(req); - - spin_lock(&inode->i_lock); - if (!nfsi->npages && nfs_have_delegation(inode, FMODE_WRITE)) - inode->i_version++; - set_bit(PG_MAPPED, &req->wb_flags); - SetPagePrivate(req->wb_page); - set_page_private(req->wb_page, (unsigned long)req); - nfsi->npages++; - kref_get(&req->wb_kref); - spin_unlock(&inode->i_lock); -} - -/* - * Remove a write request from an inode - */ -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); - - BUG_ON (!NFS_WBACK_BUSY(req)); - - spin_lock(&inode->i_lock); - set_page_private(req->wb_page, 0); - ClearPagePrivate(req->wb_page); - clear_bit(PG_MAPPED, &req->wb_flags); - nfsi->npages--; - spin_unlock(&inode->i_lock); - nfs_release_request(req); -} - -static void -nfs_mark_request_dirty(struct nfs_page *req) -{ - __set_page_dirty_nobuffers(req->wb_page); -} - -#if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) -/** - * nfs_request_add_commit_list - add request to a commit list - * @req: pointer to a struct nfs_page - * @head: commit list head - * - * This sets the PG_CLEAN bit, updates the inode global count of - * number of outstanding requests requiring a commit as well as - * the MM page stats. - * - * The caller must _not_ hold the inode->i_lock, but must be - * holding the nfs_page lock. - */ -void -nfs_request_add_commit_list(struct nfs_page *req, struct list_head *head) -{ - struct inode *inode = req->wb_context->dentry->d_inode; - - set_bit(PG_CLEAN, &(req)->wb_flags); - spin_lock(&inode->i_lock); - nfs_list_add_request(req, head); - NFS_I(inode)->ncommit++; - spin_unlock(&inode->i_lock); - inc_zone_page_state(req->wb_page, NR_UNSTABLE_NFS); - inc_bdi_stat(req->wb_page->mapping->backing_dev_info, BDI_RECLAIMABLE); - __mark_inode_dirty(inode, I_DIRTY_DATASYNC); -} -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 - * - * This clears the PG_CLEAN bit, and updates the inode global count of - * number of outstanding requests requiring a commit - * It does not update the MM page stats. - * - * The caller _must_ hold the inode->i_lock and the nfs_page lock. - */ -void -nfs_request_remove_commit_list(struct nfs_page *req) -{ - struct inode *inode = req->wb_context->dentry->d_inode; - - if (!test_and_clear_bit(PG_CLEAN, &(req)->wb_flags)) - return; - nfs_list_remove_request(req); - NFS_I(inode)->ncommit--; -} -EXPORT_SYMBOL_GPL(nfs_request_remove_commit_list); - - -/* - * Add a request to the inode's commit list. - */ -static void -nfs_mark_request_commit(struct nfs_page *req, struct pnfs_layout_segment *lseg) -{ - struct inode *inode = req->wb_context->dentry->d_inode; - - if (pnfs_mark_request_commit(req, lseg)) - return; - nfs_request_add_commit_list(req, &NFS_I(inode)->commit_list); -} - -static void -nfs_clear_page_commit(struct page *page) -{ - dec_zone_page_state(page, NR_UNSTABLE_NFS); - dec_bdi_stat(page->mapping->backing_dev_info, BDI_RECLAIMABLE); -} - -static void -nfs_clear_request_commit(struct nfs_page *req) -{ - if (test_bit(PG_CLEAN, &req->wb_flags)) { - struct inode *inode = req->wb_context->dentry->d_inode; - - if (!pnfs_clear_request_commit(req)) { - spin_lock(&inode->i_lock); - nfs_request_remove_commit_list(req); - spin_unlock(&inode->i_lock); - } - nfs_clear_page_commit(req->wb_page); - } -} - -static inline -int nfs_write_need_commit(struct nfs_write_data *data) -{ - if (data->verf.committed == NFS_DATA_SYNC) - return data->lseg == NULL; - else - return data->verf.committed != NFS_FILE_SYNC; -} - -static inline -int nfs_reschedule_unstable_write(struct nfs_page *req, - struct nfs_write_data *data) -{ - if (test_and_clear_bit(PG_NEED_COMMIT, &req->wb_flags)) { - nfs_mark_request_commit(req, data->lseg); - return 1; - } - if (test_and_clear_bit(PG_NEED_RESCHED, &req->wb_flags)) { - nfs_mark_request_dirty(req); - return 1; - } - return 0; -} -#else -static void -nfs_mark_request_commit(struct nfs_page *req, struct pnfs_layout_segment *lseg) -{ -} - -static void -nfs_clear_request_commit(struct nfs_page *req) -{ -} - -static inline -int nfs_write_need_commit(struct nfs_write_data *data) -{ - return 0; -} - -static inline -int nfs_reschedule_unstable_write(struct nfs_page *req, - struct nfs_write_data *data) -{ - return 0; -} -#endif - -#if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) -static int -nfs_need_commit(struct nfs_inode *nfsi) -{ - return nfsi->ncommit > 0; -} - -/* i_lock held by caller */ -static int -nfs_scan_commit_list(struct list_head *src, struct list_head *dst, int max, - spinlock_t *lock) -{ - struct nfs_page *req, *tmp; - int ret = 0; - - list_for_each_entry_safe(req, tmp, src, wb_list) { - if (!nfs_lock_request(req)) - continue; - if (cond_resched_lock(lock)) - list_safe_reset_next(req, tmp, wb_list); - nfs_request_remove_commit_list(req); - nfs_list_add_request(req, dst); - ret++; - if (ret == max) - break; - } - return ret; -} - -/* - * nfs_scan_commit - Scan an inode for commit requests - * @inode: NFS inode to scan - * @dst: destination list - * - * Moves requests from the inode's 'commit' request list. - * The requests are *not* checked to ensure that they form a contiguous set. - */ -static int -nfs_scan_commit(struct inode *inode, struct list_head *dst) -{ - struct nfs_inode *nfsi = NFS_I(inode); - int ret = 0; - - spin_lock(&inode->i_lock); - if (nfsi->ncommit > 0) { - const int max = INT_MAX; - - ret = nfs_scan_commit_list(&nfsi->commit_list, dst, max, - &inode->i_lock); - ret += pnfs_scan_commit_lists(inode, max - ret, - &inode->i_lock); - } - spin_unlock(&inode->i_lock); - return ret; -} - -#else -static inline int nfs_need_commit(struct nfs_inode *nfsi) -{ - return 0; -} - -static inline int nfs_scan_commit(struct inode *inode, struct list_head *dst) -{ - return 0; -} -#endif - -/* - * 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; - - if (!PagePrivate(page)) - return NULL; - - end = offset + bytes; - spin_lock(&inode->i_lock); - - for (;;) { - req = nfs_page_find_request_locked(page); - if (req == NULL) - goto out_unlock; - - 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; - - if (nfs_lock_request_dontget(req)) - break; - - /* The request is locked, so wait and then retry */ - spin_unlock(&inode->i_lock); - error = nfs_wait_on_request(req); - nfs_release_request(req); - if (error != 0) - goto out_err; - spin_lock(&inode->i_lock); - } - - /* 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; -out_unlock: - spin_unlock(&inode->i_lock); - if (req) - nfs_clear_request_commit(req); - return req; -out_flushme: - spin_unlock(&inode->i_lock); - nfs_release_request(req); - error = nfs_wb_page(inode, page); -out_err: - return ERR_PTR(error); -} - -/* - * 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->mapping->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, inode, 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(page, req->wb_pgbase, req->wb_bytes); - nfs_mark_request_dirty(req); - nfs_unlock_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_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_request(page); - if (req == NULL) - return 0; - do_flush = req->wb_page != page || req->wb_context != ctx || - req->wb_lock_context->lockowner != current->files || - req->wb_lock_context->pid != current->tgid; - nfs_release_request(req); - if (!do_flush) - return 0; - status = nfs_wb_page(page->mapping->host, page); - } while (status == 0); - return status; -} - -/* - * 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 int nfs_write_pageuptodate(struct page *page, struct inode *inode) -{ - return PageUptodate(page) && - !(NFS_I(inode)->cache_validity & (NFS_INO_REVAL_PAGECACHE|NFS_INO_INVALID_DATA)); -} - -/* - * 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 inode *inode = page->mapping->host; - int status = 0; - - 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_offset(page) + offset)); - - /* If we're not using byte range locks, and we know the page - * is up to date, it may be more efficient to extend the write - * to cover the entire page in order to avoid fragmentation - * inefficiencies. - */ - if (nfs_write_pageuptodate(page, inode) && - inode->i_flock == NULL && - !(file->f_flags & O_DSYNC)) { - count = max(count + offset, nfs_page_length(page)); - offset = 0; - } - - status = nfs_writepage_setup(ctx, page, offset, count); - if (status < 0) - nfs_set_pageerror(page); - else - __set_page_dirty_nobuffers(page); - - dprintk("NFS: nfs_updatepage returns %d (isize %lld)\n", - status, (long long)i_size_read(inode)); - return status; -} - -static void nfs_writepage_release(struct nfs_page *req, - struct nfs_write_data *data) -{ - struct page *page = req->wb_page; - - if (PageError(req->wb_page) || !nfs_reschedule_unstable_write(req, data)) - nfs_inode_remove_request(req); - nfs_unlock_request(req); - nfs_end_page_writeback(page); -} - -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; -} - -int nfs_initiate_write(struct nfs_write_data *data, - struct rpc_clnt *clnt, - const struct rpc_call_ops *call_ops, - int how) -{ - struct inode *inode = data->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->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, - .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 = 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_page *req, - struct nfs_write_data *data, - unsigned int count, unsigned int offset, - int how) -{ - struct inode *inode = req->wb_context->dentry->d_inode; - - /* Set up the RPC argument and reply structs - * NB: take care not to mess about with data->commit et al. */ - - data->req = req; - data->inode = inode = req->wb_context->dentry->d_inode; - data->cred = req->wb_context->cred; - - data->args.fh = NFS_FH(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->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_need_commit(NFS_I(inode))) - 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->args.context->dentry->d_inode; - - return nfs_initiate_write(data, NFS_CLIENT(inode), call_ops, how); -} - -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_entry(head->next, 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; -} - -/* 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) -{ - struct page *page = req->wb_page; - - nfs_mark_request_dirty(req); - nfs_unlock_request(req); - nfs_end_page_writeback(page); -} - -/* - * 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 list_head *res) -{ - struct nfs_page *req = nfs_list_entry(desc->pg_list.next); - struct page *page = req->wb_page; - struct nfs_write_data *data; - size_t wsize = desc->pg_bsize, nbytes; - unsigned int offset; - int requests = 0; - int ret = 0; - - nfs_list_remove_request(req); - - if ((desc->pg_ioflags & FLUSH_COND_STABLE) && - (desc->pg_moreio || NFS_I(desc->pg_inode)->ncommit || - 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(1); - if (!data) - goto out_bad; - data->pagevec[0] = page; - nfs_write_rpcsetup(req, data, len, offset, desc->pg_ioflags); - list_add(&data->list, res); - requests++; - nbytes -= len; - offset += len; - } while (nbytes != 0); - atomic_set(&req->wb_complete, requests); - desc->pg_rpc_callops = &nfs_write_partial_ops; - return ret; - -out_bad: - while (!list_empty(res)) { - data = list_entry(res->next, struct nfs_write_data, list); - list_del(&data->list); - nfs_writedata_release(data); - } - nfs_redirty_request(req); - return -ENOMEM; -} - -/* - * 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 list_head *res) -{ - struct nfs_page *req; - struct page **pages; - struct nfs_write_data *data; - struct list_head *head = &desc->pg_list; - int ret = 0; - - data = nfs_writedata_alloc(nfs_page_array_len(desc->pg_base, - desc->pg_count)); - if (!data) { - while (!list_empty(head)) { - req = nfs_list_entry(head->next); - nfs_list_remove_request(req); - nfs_redirty_request(req); - } - ret = -ENOMEM; - goto out; - } - pages = data->pagevec; - while (!list_empty(head)) { - req = nfs_list_entry(head->next); - nfs_list_remove_request(req); - nfs_list_add_request(req, &data->pages); - *pages++ = req->wb_page; - } - req = nfs_list_entry(data->pages.next); - - if ((desc->pg_ioflags & FLUSH_COND_STABLE) && - (desc->pg_moreio || NFS_I(desc->pg_inode)->ncommit)) - desc->pg_ioflags &= ~FLUSH_COND_STABLE; - - /* Set up the argument struct */ - nfs_write_rpcsetup(req, data, desc->pg_count, 0, desc->pg_ioflags); - list_add(&data->list, res); - desc->pg_rpc_callops = &nfs_write_full_ops; -out: - return ret; -} - -int nfs_generic_flush(struct nfs_pageio_descriptor *desc, struct list_head *head) -{ - if (desc->pg_bsize < PAGE_CACHE_SIZE) - return nfs_flush_multi(desc, head); - return nfs_flush_one(desc, head); -} - -static int nfs_generic_pg_writepages(struct nfs_pageio_descriptor *desc) -{ - LIST_HEAD(head); - int ret; - - ret = nfs_generic_flush(desc, &head); - if (ret == 0) - ret = nfs_do_multiple_writes(&head, desc->pg_rpc_callops, - desc->pg_ioflags); - 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_mds(struct nfs_pageio_descriptor *pgio, - struct inode *inode, int ioflags) -{ - nfs_pageio_init(pgio, inode, &nfs_pageio_write_ops, - NFS_SERVER(inode)->wsize, ioflags); -} - -void nfs_pageio_reset_write_mds(struct nfs_pageio_descriptor *pgio) -{ - pgio->pg_ops = &nfs_pageio_write_ops; - pgio->pg_bsize = NFS_SERVER(pgio->pg_inode)->wsize; -} -EXPORT_SYMBOL_GPL(nfs_pageio_reset_write_mds); - -static void nfs_pageio_init_write(struct nfs_pageio_descriptor *pgio, - struct inode *inode, int ioflags) -{ - if (!pnfs_pageio_init_write(pgio, inode, ioflags)) - nfs_pageio_init_write_mds(pgio, inode, ioflags); -} - -/* - * Handle a write reply that flushed part of a page. - */ -static void nfs_writeback_done_partial(struct rpc_task *task, void *calldata) -{ - struct nfs_write_data *data = calldata; - - dprintk("NFS: %5u write(%s/%lld %d@%lld)", - task->tk_pid, - data->req->wb_context->dentry->d_inode->i_sb->s_id, - (long long) - NFS_FILEID(data->req->wb_context->dentry->d_inode), - data->req->wb_bytes, (long long)req_offset(data->req)); - - nfs_writeback_done(task, data); -} - -static void nfs_writeback_release_partial(void *calldata) -{ - struct nfs_write_data *data = calldata; - struct nfs_page *req = data->req; - struct page *page = req->wb_page; - int status = data->task.tk_status; - - if (status < 0) { - nfs_set_pageerror(page); - nfs_context_set_write_error(req->wb_context, status); - dprintk(", error = %d\n", status); - goto out; - } - - if (nfs_write_need_commit(data)) { - struct inode *inode = page->mapping->host; - - spin_lock(&inode->i_lock); - if (test_bit(PG_NEED_RESCHED, &req->wb_flags)) { - /* Do nothing we need to resend the writes */ - } else if (!test_and_set_bit(PG_NEED_COMMIT, &req->wb_flags)) { - memcpy(&req->wb_verf, &data->verf, sizeof(req->wb_verf)); - dprintk(" defer commit\n"); - } else if (memcmp(&req->wb_verf, &data->verf, sizeof(req->wb_verf))) { - set_bit(PG_NEED_RESCHED, &req->wb_flags); - clear_bit(PG_NEED_COMMIT, &req->wb_flags); - dprintk(" server reboot detected\n"); - } - spin_unlock(&inode->i_lock); - } else - dprintk(" OK\n"); - -out: - if (atomic_dec_and_test(&req->wb_complete)) - nfs_writepage_release(req, data); - nfs_writedata_release(calldata); -} - -void nfs_write_prepare(struct rpc_task *task, void *calldata) -{ - struct nfs_write_data *data = calldata; - NFS_PROTO(data->inode)->write_rpc_prepare(task, data); -} - -static const struct rpc_call_ops nfs_write_partial_ops = { - .rpc_call_prepare = nfs_write_prepare, - .rpc_call_done = nfs_writeback_done_partial, - .rpc_release = nfs_writeback_release_partial, -}; - -/* - * 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_full(struct rpc_task *task, void *calldata) -{ - struct nfs_write_data *data = calldata; - - nfs_writeback_done(task, data); -} - -static void nfs_writeback_release_full(void *calldata) -{ - struct nfs_write_data *data = calldata; - int status = data->task.tk_status; - - /* Update attributes as result of writeback. */ - while (!list_empty(&data->pages)) { - struct nfs_page *req = nfs_list_entry(data->pages.next); - struct page *page = req->wb_page; - - nfs_list_remove_request(req); - - dprintk("NFS: %5u write (%s/%lld %d@%lld)", - data->task.tk_pid, - req->wb_context->dentry->d_inode->i_sb->s_id, - (long long)NFS_FILEID(req->wb_context->dentry->d_inode), - req->wb_bytes, - (long long)req_offset(req)); - - if (status < 0) { - nfs_set_pageerror(page); - nfs_context_set_write_error(req->wb_context, status); - dprintk(", error = %d\n", status); - goto remove_request; - } - - if (nfs_write_need_commit(data)) { - memcpy(&req->wb_verf, &data->verf, sizeof(req->wb_verf)); - nfs_mark_request_commit(req, data->lseg); - dprintk(" marked for commit\n"); - goto next; - } - dprintk(" OK\n"); -remove_request: - nfs_inode_remove_request(req); - next: - nfs_unlock_request(req); - nfs_end_page_writeback(page); - } - nfs_writedata_release(calldata); -} - -static const struct rpc_call_ops nfs_write_full_ops = { - .rpc_call_prepare = nfs_write_prepare, - .rpc_call_done = nfs_writeback_done_full, - .rpc_release = nfs_writeback_release_full, -}; - - -/* - * This function is called when the WRITE call is complete. - */ -void nfs_writeback_done(struct rpc_task *task, struct nfs_write_data *data) -{ - struct nfs_writeargs *argp = &data->args; - struct nfs_writeres *resp = &data->res; - 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 - * 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(data->inode)->write_done(task, data); - if (status != 0) - return; - nfs_add_stats(data->inode, NFSIOS_SERVERWRITTENBYTES, resp->count); - -#if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) - if (resp->verf->committed < argp->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(data->inode)->nfs_client->cl_hostname, - resp->verf->committed, argp->stable); - complain = jiffies + 300 * HZ; - } - } -#endif - /* Is this a short write? */ - if (task->tk_status >= 0 && resp->count < argp->count) { - static unsigned long complain; - - nfs_inc_stats(data->inode, NFSIOS_SHORTWRITE); - - /* Has the server at least made some progress? */ - if (resp->count != 0) { - /* Was this an NFSv2 write or an NFSv3 stable write? */ - if (resp->verf->committed != NFS_UNSTABLE) { - /* Resend from where the server left off */ - data->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; - } - rpc_restart_call_prepare(task); - return; - } - if (time_before(complain, jiffies)) { - printk(KERN_WARNING - "NFS: Server wrote zero bytes, expected %u.\n", - argp->count); - complain = jiffies + 300 * HZ; - } - /* Can't do anything about it except throw an error. */ - task->tk_status = -EIO; - } - return; -} - - -#if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) -static int nfs_commit_set_lock(struct nfs_inode *nfsi, int may_wait) -{ - int ret; - - if (!test_and_set_bit(NFS_INO_COMMIT, &nfsi->flags)) - return 1; - if (!may_wait) - return 0; - ret = out_of_line_wait_on_bit_lock(&nfsi->flags, - NFS_INO_COMMIT, - nfs_wait_bit_killable, - TASK_KILLABLE); - return (ret < 0) ? ret : 1; -} - -void nfs_commit_clear_lock(struct nfs_inode *nfsi) -{ - clear_bit(NFS_INO_COMMIT, &nfsi->flags); - smp_mb__after_clear_bit(); - wake_up_bit(&nfsi->flags, NFS_INO_COMMIT); -} -EXPORT_SYMBOL_GPL(nfs_commit_clear_lock); - -void nfs_commitdata_release(void *data) -{ - struct nfs_write_data *wdata = data; - - put_nfs_open_context(wdata->args.context); - nfs_commit_free(wdata); -} -EXPORT_SYMBOL_GPL(nfs_commitdata_release); - -int nfs_initiate_commit(struct nfs_write_data *data, struct rpc_clnt *clnt, - const struct rpc_call_ops *call_ops, - int how) -{ - 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, - .priority = priority, - }; - /* Set up the initial task struct. */ - NFS_PROTO(data->inode)->commit_setup(data, &msg); - - dprintk("NFS: %5u initiated commit call\n", data->task.tk_pid); - - 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); - -/* - * Set up the argument/result storage required for the RPC call. - */ -void nfs_init_commit(struct nfs_write_data *data, - struct list_head *head, - struct pnfs_layout_segment *lseg) -{ - struct nfs_page *first = nfs_list_entry(head->next); - struct inode *inode = first->wb_context->dentry->d_inode; - - /* Set up the RPC argument and reply structs - * NB: take care not to mess about with data->commit et al. */ - - list_splice_init(head, &data->pages); - - data->inode = inode; - data->cred = first->wb_context->cred; - data->lseg = lseg; /* reference transferred */ - data->mds_ops = &nfs_commit_ops; - - 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->args.context = get_nfs_open_context(first->wb_context); - data->res.count = 0; - 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_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); - dec_zone_page_state(req->wb_page, NR_UNSTABLE_NFS); - dec_bdi_stat(req->wb_page->mapping->backing_dev_info, - BDI_RECLAIMABLE); - nfs_unlock_request(req); - } -} -EXPORT_SYMBOL_GPL(nfs_retry_commit); - -/* - * Commit dirty pages - */ -static int -nfs_commit_list(struct inode *inode, struct list_head *head, int how) -{ - struct nfs_write_data *data; - - data = nfs_commitdata_alloc(); - - if (!data) - goto out_bad; - - /* Set up the argument struct */ - nfs_init_commit(data, head, NULL); - return nfs_initiate_commit(data, NFS_CLIENT(inode), data->mds_ops, how); - out_bad: - nfs_retry_commit(head, NULL); - nfs_commit_clear_lock(NFS_I(inode)); - return -ENOMEM; -} - -/* - * COMMIT call returned - */ -static void nfs_commit_done(struct rpc_task *task, void *calldata) -{ - struct nfs_write_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); -} - -void nfs_commit_release_pages(struct nfs_write_data *data) -{ - struct nfs_page *req; - int status = data->task.tk_status; - - while (!list_empty(&data->pages)) { - req = nfs_list_entry(data->pages.next); - nfs_list_remove_request(req); - nfs_clear_page_commit(req->wb_page); - - dprintk("NFS: commit (%s/%lld %d@%lld)", - req->wb_context->dentry->d_sb->s_id, - (long long)NFS_FILEID(req->wb_context->dentry->d_inode), - req->wb_bytes, - (long long)req_offset(req)); - if (status < 0) { - nfs_context_set_write_error(req->wb_context, status); - nfs_inode_remove_request(req); - dprintk(", error = %d\n", status); - goto next; - } - - /* Okay, COMMIT succeeded, apparently. Check the verifier - * returned by the server against all stored verfs. */ - if (!memcmp(req->wb_verf.verifier, data->verf.verifier, sizeof(data->verf.verifier))) { - /* We have a match */ - nfs_inode_remove_request(req); - dprintk(" OK\n"); - goto next; - } - /* We have a mismatch. Write the page again */ - dprintk(" mismatch\n"); - nfs_mark_request_dirty(req); - next: - nfs_unlock_request(req); - } -} -EXPORT_SYMBOL_GPL(nfs_commit_release_pages); - -static void nfs_commit_release(void *calldata) -{ - struct nfs_write_data *data = calldata; - - nfs_commit_release_pages(data); - nfs_commit_clear_lock(NFS_I(data->inode)); - nfs_commitdata_release(calldata); -} - -static const struct rpc_call_ops nfs_commit_ops = { - .rpc_call_prepare = nfs_write_prepare, - .rpc_call_done = nfs_commit_done, - .rpc_release = nfs_commit_release, -}; - -int nfs_commit_inode(struct inode *inode, int how) -{ - LIST_HEAD(head); - int may_wait = how & FLUSH_SYNC; - int res; - - res = nfs_commit_set_lock(NFS_I(inode), may_wait); - if (res <= 0) - goto out_mark_dirty; - res = nfs_scan_commit(inode, &head); - if (res) { - int error; - - error = pnfs_commit_list(inode, &head, how); - if (error == PNFS_NOT_ATTEMPTED) - error = nfs_commit_list(inode, &head, how); - if (error < 0) - return error; - if (!may_wait) - goto out_mark_dirty; - error = wait_on_bit(&NFS_I(inode)->flags, - NFS_INO_COMMIT, - nfs_wait_bit_killable, - TASK_KILLABLE); - if (error < 0) - return error; - } else - nfs_commit_clear_lock(NFS_I(inode)); - return res; - /* Note: If we exit without ensuring that the commit is complete, - * we must mark the inode as dirty. Otherwise, future calls to - * sync_inode() with the WB_SYNC_ALL flag set will fail to ensure - * that the data is on the disk. - */ -out_mark_dirty: - __mark_inode_dirty(inode, I_DIRTY_DATASYNC); - return res; -} - -static int nfs_commit_unstable_pages(struct inode *inode, struct writeback_control *wbc) -{ - struct nfs_inode *nfsi = NFS_I(inode); - int flags = FLUSH_SYNC; - int ret = 0; - - /* no commits means nothing needs to be done */ - if (!nfsi->ncommit) - return ret; - - if (wbc->sync_mode == WB_SYNC_NONE) { - /* Don't commit yet if this is a non-blocking flush and there - * are a lot of outstanding writes for this mapping. - */ - if (nfsi->ncommit <= (nfsi->npages >> 1)) - goto out_mark_dirty; - - /* don't wait for the COMMIT response */ - flags = 0; - } - - ret = nfs_commit_inode(inode, flags); - if (ret >= 0) { - if (wbc->sync_mode == WB_SYNC_NONE) { - if (ret < wbc->nr_to_write) - wbc->nr_to_write -= ret; - else - wbc->nr_to_write = 0; - } - return 0; - } -out_mark_dirty: - __mark_inode_dirty(inode, I_DIRTY_DATASYNC); - return ret; -} -#else -static int nfs_commit_unstable_pages(struct inode *inode, struct writeback_control *wbc) -{ - return 0; -} -#endif - -int nfs_write_inode(struct inode *inode, struct writeback_control *wbc) -{ - int ret; - - ret = nfs_commit_unstable_pages(inode, wbc); - if (ret >= 0 && test_bit(NFS_INO_LAYOUTCOMMIT, &NFS_I(inode)->flags)) { - int status; - bool sync = true; - - if (wbc->sync_mode == WB_SYNC_NONE) - sync = false; - - status = pnfs_layoutcommit_inode(inode, sync); - if (status < 0) - return status; - } - return ret; -} - -/* - * flush the inode to disk. - */ -int nfs_wb_all(struct inode *inode) -{ - struct writeback_control wbc = { - .sync_mode = WB_SYNC_ALL, - .nr_to_write = LONG_MAX, - .range_start = 0, - .range_end = LLONG_MAX, - }; - - return sync_inode(inode, &wbc); -} - -int nfs_wb_page_cancel(struct inode *inode, struct page *page) -{ - struct nfs_page *req; - int ret = 0; - - BUG_ON(!PageLocked(page)); - for (;;) { - wait_on_page_writeback(page); - req = nfs_page_find_request(page); - if (req == NULL) - break; - if (nfs_lock_request_dontget(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_request(req); - break; - } - ret = nfs_wait_on_request(req); - nfs_release_request(req); - if (ret < 0) - break; - } - 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_offset(page); - loff_t range_end = range_start + (loff_t)(PAGE_CACHE_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; - - 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; - } - if (!PagePrivate(page)) - break; - ret = nfs_commit_inode(inode, FLUSH_SYNC); - if (ret < 0) - goto out_error; - } - return 0; -out_error: - 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; - - nfs_fscache_release_page(page, GFP_KERNEL); - - 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_write_data), - 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) - return -ENOMEM; - - nfs_commit_mempool = mempool_create_slab_pool(MIN_POOL_COMMIT, - nfs_wdata_cachep); - if (nfs_commit_mempool == NULL) - return -ENOMEM; - - /* - * 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; -} - -void nfs_destroy_writepagecache(void) -{ - mempool_destroy(nfs_commit_mempool); - mempool_destroy(nfs_wdata_mempool); - kmem_cache_destroy(nfs_wdata_cachep); -} - |