From 1d3576fd10f0d7a104204267b81cf84a07028dad Mon Sep 17 00:00:00 2001 From: Sage Weil Date: Tue, 6 Oct 2009 11:31:09 -0700 Subject: ceph: address space operations The ceph address space methods are concerned primarily with managing the dirty page accounting in the inode, which (among other things) must keep track of which snapshot context each page was dirtied in, and ensure that dirty data is written out to the OSDs in snapshort order. A writepage() on a page that is not currently writeable due to snapshot writeback ordering constraints is ignored (it was presumably called from kswapd). Signed-off-by: Sage Weil --- fs/ceph/addr.c | 1115 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 1115 insertions(+) create mode 100644 fs/ceph/addr.c (limited to 'fs/ceph/addr.c') diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c new file mode 100644 index 000000000000..c7d673ffe023 --- /dev/null +++ b/fs/ceph/addr.c @@ -0,0 +1,1115 @@ +#include "ceph_debug.h" + +#include +#include +#include +#include +#include /* generic_writepages */ +#include +#include + +#include "super.h" +#include "osd_client.h" + +/* + * Ceph address space ops. + * + * There are a few funny things going on here. + * + * The page->private field is used to reference a struct + * ceph_snap_context for _every_ dirty page. This indicates which + * snapshot the page was logically dirtied in, and thus which snap + * context needs to be associated with the osd write during writeback. + * + * Similarly, struct ceph_inode_info maintains a set of counters to + * count dirty pages on the inode. In the absense of snapshots, + * i_wrbuffer_ref == i_wrbuffer_ref_head == the dirty page count. + * + * When a snapshot is taken (that is, when the client receives + * notification that a snapshot was taken), each inode with caps and + * with dirty pages (dirty pages implies there is a cap) gets a new + * ceph_cap_snap in the i_cap_snaps list (which is sorted in ascending + * order, new snaps go to the tail). The i_wrbuffer_ref_head count is + * moved to capsnap->dirty. (Unless a sync write is currently in + * progress. In that case, the capsnap is said to be "pending", new + * writes cannot start, and the capsnap isn't "finalized" until the + * write completes (or fails) and a final size/mtime for the inode for + * that snap can be settled upon.) i_wrbuffer_ref_head is reset to 0. + * + * On writeback, we must submit writes to the osd IN SNAP ORDER. So, + * we look for the first capsnap in i_cap_snaps and write out pages in + * that snap context _only_. Then we move on to the next capsnap, + * eventually reaching the "live" or "head" context (i.e., pages that + * are not yet snapped) and are writing the most recently dirtied + * pages. + * + * Invalidate and so forth must take care to ensure the dirty page + * accounting is preserved. + */ + + +/* + * Dirty a page. Optimistically adjust accounting, on the assumption + * that we won't race with invalidate. If we do, readjust. + */ +static int ceph_set_page_dirty(struct page *page) +{ + struct address_space *mapping = page->mapping; + struct inode *inode; + struct ceph_inode_info *ci; + int undo = 0; + struct ceph_snap_context *snapc; + + if (unlikely(!mapping)) + return !TestSetPageDirty(page); + + if (TestSetPageDirty(page)) { + dout("%p set_page_dirty %p idx %lu -- already dirty\n", + mapping->host, page, page->index); + return 0; + } + + inode = mapping->host; + ci = ceph_inode(inode); + + /* + * Note that we're grabbing a snapc ref here without holding + * any locks! + */ + snapc = ceph_get_snap_context(ci->i_snap_realm->cached_context); + + /* dirty the head */ + spin_lock(&inode->i_lock); + if (ci->i_wrbuffer_ref_head == 0) + ci->i_head_snapc = ceph_get_snap_context(snapc); + ++ci->i_wrbuffer_ref_head; + if (ci->i_wrbuffer_ref == 0) + igrab(inode); + ++ci->i_wrbuffer_ref; + dout("%p set_page_dirty %p idx %lu head %d/%d -> %d/%d " + "snapc %p seq %lld (%d snaps)\n", + mapping->host, page, page->index, + ci->i_wrbuffer_ref-1, ci->i_wrbuffer_ref_head-1, + ci->i_wrbuffer_ref, ci->i_wrbuffer_ref_head, + snapc, snapc->seq, snapc->num_snaps); + spin_unlock(&inode->i_lock); + + /* now adjust page */ + spin_lock_irq(&mapping->tree_lock); + if (page->mapping) { /* Race with truncate? */ + WARN_ON_ONCE(!PageUptodate(page)); + + if (mapping_cap_account_dirty(mapping)) { + __inc_zone_page_state(page, NR_FILE_DIRTY); + __inc_bdi_stat(mapping->backing_dev_info, + BDI_RECLAIMABLE); + task_io_account_write(PAGE_CACHE_SIZE); + } + radix_tree_tag_set(&mapping->page_tree, + page_index(page), PAGECACHE_TAG_DIRTY); + + /* + * Reference snap context in page->private. Also set + * PagePrivate so that we get invalidatepage callback. + */ + page->private = (unsigned long)snapc; + SetPagePrivate(page); + } else { + dout("ANON set_page_dirty %p (raced truncate?)\n", page); + undo = 1; + } + + spin_unlock_irq(&mapping->tree_lock); + + if (undo) + /* whoops, we failed to dirty the page */ + ceph_put_wrbuffer_cap_refs(ci, 1, snapc); + + __mark_inode_dirty(mapping->host, I_DIRTY_PAGES); + + BUG_ON(!PageDirty(page)); + return 1; +} + +/* + * If we are truncating the full page (i.e. offset == 0), adjust the + * dirty page counters appropriately. Only called if there is private + * data on the page. + */ +static void ceph_invalidatepage(struct page *page, unsigned long offset) +{ + struct inode *inode = page->mapping->host; + struct ceph_inode_info *ci; + struct ceph_snap_context *snapc = (void *)page->private; + + BUG_ON(!PageLocked(page)); + BUG_ON(!page->private); + BUG_ON(!PagePrivate(page)); + BUG_ON(!page->mapping); + + /* + * We can get non-dirty pages here due to races between + * set_page_dirty and truncate_complete_page; just spit out a + * warning, in case we end up with accounting problems later. + */ + if (!PageDirty(page)) + pr_err("%p invalidatepage %p page not dirty\n", inode, page); + + if (offset == 0) + ClearPageChecked(page); + + ci = ceph_inode(inode); + if (offset == 0) { + dout("%p invalidatepage %p idx %lu full dirty page %lu\n", + inode, page, page->index, offset); + ceph_put_wrbuffer_cap_refs(ci, 1, snapc); + ceph_put_snap_context(snapc); + page->private = 0; + ClearPagePrivate(page); + } else { + dout("%p invalidatepage %p idx %lu partial dirty page\n", + inode, page, page->index); + } +} + +/* just a sanity check */ +static int ceph_releasepage(struct page *page, gfp_t g) +{ + struct inode *inode = page->mapping ? page->mapping->host : NULL; + dout("%p releasepage %p idx %lu\n", inode, page, page->index); + WARN_ON(PageDirty(page)); + WARN_ON(page->private); + WARN_ON(PagePrivate(page)); + return 0; +} + +/* + * read a single page, without unlocking it. + */ +static int readpage_nounlock(struct file *filp, struct page *page) +{ + struct inode *inode = filp->f_dentry->d_inode; + struct ceph_inode_info *ci = ceph_inode(inode); + struct ceph_osd_client *osdc = &ceph_inode_to_client(inode)->osdc; + int err = 0; + u64 len = PAGE_CACHE_SIZE; + + dout("readpage inode %p file %p page %p index %lu\n", + inode, filp, page, page->index); + err = ceph_osdc_readpages(osdc, ceph_vino(inode), &ci->i_layout, + page->index << PAGE_CACHE_SHIFT, &len, + ci->i_truncate_seq, ci->i_truncate_size, + &page, 1); + if (err == -ENOENT) + err = 0; + if (err < 0) { + SetPageError(page); + goto out; + } else if (err < PAGE_CACHE_SIZE) { + /* zero fill remainder of page */ + zero_user_segment(page, err, PAGE_CACHE_SIZE); + } + SetPageUptodate(page); + +out: + return err < 0 ? err : 0; +} + +static int ceph_readpage(struct file *filp, struct page *page) +{ + int r = readpage_nounlock(filp, page); + unlock_page(page); + return r; +} + +/* + * Build a vector of contiguous pages from the provided page list. + */ +static struct page **page_vector_from_list(struct list_head *page_list, + unsigned *nr_pages) +{ + struct page **pages; + struct page *page; + int next_index, contig_pages = 0; + + /* build page vector */ + pages = kmalloc(sizeof(*pages) * *nr_pages, GFP_NOFS); + if (!pages) + return ERR_PTR(-ENOMEM); + + BUG_ON(list_empty(page_list)); + next_index = list_entry(page_list->prev, struct page, lru)->index; + list_for_each_entry_reverse(page, page_list, lru) { + if (page->index == next_index) { + dout("readpages page %d %p\n", contig_pages, page); + pages[contig_pages] = page; + contig_pages++; + next_index++; + } else { + break; + } + } + *nr_pages = contig_pages; + return pages; +} + +/* + * Read multiple pages. Leave pages we don't read + unlock in page_list; + * the caller (VM) cleans them up. + */ +static int ceph_readpages(struct file *file, struct address_space *mapping, + struct list_head *page_list, unsigned nr_pages) +{ + struct inode *inode = file->f_dentry->d_inode; + struct ceph_inode_info *ci = ceph_inode(inode); + struct ceph_osd_client *osdc = &ceph_inode_to_client(inode)->osdc; + int rc = 0; + struct page **pages; + struct pagevec pvec; + loff_t offset; + u64 len; + + dout("readpages %p file %p nr_pages %d\n", + inode, file, nr_pages); + + pages = page_vector_from_list(page_list, &nr_pages); + if (IS_ERR(pages)) + return PTR_ERR(pages); + + /* guess read extent */ + offset = pages[0]->index << PAGE_CACHE_SHIFT; + len = nr_pages << PAGE_CACHE_SHIFT; + rc = ceph_osdc_readpages(osdc, ceph_vino(inode), &ci->i_layout, + offset, &len, + ci->i_truncate_seq, ci->i_truncate_size, + pages, nr_pages); + if (rc == -ENOENT) + rc = 0; + if (rc < 0) + goto out; + + /* set uptodate and add to lru in pagevec-sized chunks */ + pagevec_init(&pvec, 0); + for (; !list_empty(page_list) && len > 0; + rc -= PAGE_CACHE_SIZE, len -= PAGE_CACHE_SIZE) { + struct page *page = + list_entry(page_list->prev, struct page, lru); + + list_del(&page->lru); + + if (rc < (int)PAGE_CACHE_SIZE) { + /* zero (remainder of) page */ + int s = rc < 0 ? 0 : rc; + zero_user_segment(page, s, PAGE_CACHE_SIZE); + } + + if (add_to_page_cache(page, mapping, page->index, GFP_NOFS)) { + page_cache_release(page); + dout("readpages %p add_to_page_cache failed %p\n", + inode, page); + continue; + } + dout("readpages %p adding %p idx %lu\n", inode, page, + page->index); + flush_dcache_page(page); + SetPageUptodate(page); + unlock_page(page); + if (pagevec_add(&pvec, page) == 0) + pagevec_lru_add_file(&pvec); /* add to lru */ + } + pagevec_lru_add_file(&pvec); + rc = 0; + +out: + kfree(pages); + return rc; +} + +/* + * Get ref for the oldest snapc for an inode with dirty data... that is, the + * only snap context we are allowed to write back. + * + * Caller holds i_lock. + */ +static struct ceph_snap_context *__get_oldest_context(struct inode *inode, + u64 *snap_size) +{ + struct ceph_inode_info *ci = ceph_inode(inode); + struct ceph_snap_context *snapc = NULL; + struct ceph_cap_snap *capsnap = NULL; + + list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) { + dout(" cap_snap %p snapc %p has %d dirty pages\n", capsnap, + capsnap->context, capsnap->dirty_pages); + if (capsnap->dirty_pages) { + snapc = ceph_get_snap_context(capsnap->context); + if (snap_size) + *snap_size = capsnap->size; + break; + } + } + if (!snapc && ci->i_snap_realm) { + snapc = ceph_get_snap_context(ci->i_snap_realm->cached_context); + dout(" head snapc %p has %d dirty pages\n", + snapc, ci->i_wrbuffer_ref_head); + } + return snapc; +} + +static struct ceph_snap_context *get_oldest_context(struct inode *inode, + u64 *snap_size) +{ + struct ceph_snap_context *snapc = NULL; + + spin_lock(&inode->i_lock); + snapc = __get_oldest_context(inode, snap_size); + spin_unlock(&inode->i_lock); + return snapc; +} + +/* + * Write a single page, but leave the page locked. + * + * If we get a write error, set the page error bit, but still adjust the + * dirty page accounting (i.e., page is no longer dirty). + */ +static int writepage_nounlock(struct page *page, struct writeback_control *wbc) +{ + struct inode *inode; + struct ceph_inode_info *ci; + struct ceph_osd_client *osdc; + loff_t page_off = page->index << PAGE_CACHE_SHIFT; + int len = PAGE_CACHE_SIZE; + loff_t i_size; + int err = 0; + struct ceph_snap_context *snapc; + u64 snap_size = 0; + + dout("writepage %p idx %lu\n", page, page->index); + + if (!page->mapping || !page->mapping->host) { + dout("writepage %p - no mapping\n", page); + return -EFAULT; + } + inode = page->mapping->host; + ci = ceph_inode(inode); + osdc = &ceph_inode_to_client(inode)->osdc; + + /* verify this is a writeable snap context */ + snapc = (void *)page->private; + if (snapc == NULL) { + dout("writepage %p page %p not dirty?\n", inode, page); + goto out; + } + if (snapc != get_oldest_context(inode, &snap_size)) { + dout("writepage %p page %p snapc %p not writeable - noop\n", + inode, page, (void *)page->private); + /* we should only noop if called by kswapd */ + WARN_ON((current->flags & PF_MEMALLOC) == 0); + goto out; + } + + /* is this a partial page at end of file? */ + if (snap_size) + i_size = snap_size; + else + i_size = i_size_read(inode); + if (i_size < page_off + len) + len = i_size - page_off; + + dout("writepage %p page %p index %lu on %llu~%u\n", + inode, page, page->index, page_off, len); + + set_page_writeback(page); + err = ceph_osdc_writepages(osdc, ceph_vino(inode), + &ci->i_layout, snapc, + page_off, len, + ci->i_truncate_seq, ci->i_truncate_size, + &inode->i_mtime, + &page, 1, 0, 0, true); + if (err < 0) { + dout("writepage setting page/mapping error %d %p\n", err, page); + SetPageError(page); + mapping_set_error(&inode->i_data, err); + if (wbc) + wbc->pages_skipped++; + } else { + dout("writepage cleaned page %p\n", page); + err = 0; /* vfs expects us to return 0 */ + } + page->private = 0; + ClearPagePrivate(page); + end_page_writeback(page); + ceph_put_wrbuffer_cap_refs(ci, 1, snapc); + ceph_put_snap_context(snapc); +out: + return err; +} + +static int ceph_writepage(struct page *page, struct writeback_control *wbc) +{ + int err = writepage_nounlock(page, wbc); + unlock_page(page); + return err; +} + + +/* + * lame release_pages helper. release_pages() isn't exported to + * modules. + */ +static void ceph_release_pages(struct page **pages, int num) +{ + struct pagevec pvec; + int i; + + pagevec_init(&pvec, 0); + for (i = 0; i < num; i++) { + if (pagevec_add(&pvec, pages[i]) == 0) + pagevec_release(&pvec); + } + pagevec_release(&pvec); +} + + +/* + * async writeback completion handler. + * + * If we get an error, set the mapping error bit, but not the individual + * page error bits. + */ +static void writepages_finish(struct ceph_osd_request *req, + struct ceph_msg *msg) +{ + struct inode *inode = req->r_inode; + struct ceph_osd_reply_head *replyhead; + struct ceph_osd_op *op; + struct ceph_inode_info *ci = ceph_inode(inode); + unsigned wrote; + loff_t offset = req->r_pages[0]->index << PAGE_CACHE_SHIFT; + struct page *page; + int i; + struct ceph_snap_context *snapc = req->r_snapc; + struct address_space *mapping = inode->i_mapping; + struct writeback_control *wbc = req->r_wbc; + __s32 rc = -EIO; + u64 bytes = 0; + + /* parse reply */ + replyhead = msg->front.iov_base; + WARN_ON(le32_to_cpu(replyhead->num_ops) == 0); + op = (void *)(replyhead + 1); + rc = le32_to_cpu(replyhead->result); + bytes = le64_to_cpu(op->extent.length); + + if (rc >= 0) { + wrote = (bytes + (offset & ~PAGE_CACHE_MASK) + ~PAGE_CACHE_MASK) + >> PAGE_CACHE_SHIFT; + WARN_ON(wrote != req->r_num_pages); + } else { + wrote = 0; + mapping_set_error(mapping, rc); + } + dout("writepages_finish %p rc %d bytes %llu wrote %d (pages)\n", + inode, rc, bytes, wrote); + + /* clean all pages */ + for (i = 0; i < req->r_num_pages; i++) { + page = req->r_pages[i]; + BUG_ON(!page); + WARN_ON(!PageUptodate(page)); + + if (i >= wrote) { + dout("inode %p skipping page %p\n", inode, page); + wbc->pages_skipped++; + } + page->private = 0; + ClearPagePrivate(page); + ceph_put_snap_context(snapc); + dout("unlocking %d %p\n", i, page); + end_page_writeback(page); + unlock_page(page); + } + dout("%p wrote+cleaned %d pages\n", inode, wrote); + ceph_put_wrbuffer_cap_refs(ci, req->r_num_pages, snapc); + + ceph_release_pages(req->r_pages, req->r_num_pages); + if (req->r_pages_from_pool) + mempool_free(req->r_pages, + ceph_client(inode->i_sb)->wb_pagevec_pool); + else + kfree(req->r_pages); + ceph_osdc_put_request(req); +} + +/* + * allocate a page vec, either directly, or if necessary, via a the + * mempool. we avoid the mempool if we can because req->r_num_pages + * may be less than the maximum write size. + */ +static void alloc_page_vec(struct ceph_client *client, + struct ceph_osd_request *req) +{ + req->r_pages = kmalloc(sizeof(struct page *) * req->r_num_pages, + GFP_NOFS); + if (!req->r_pages) { + req->r_pages = mempool_alloc(client->wb_pagevec_pool, GFP_NOFS); + req->r_pages_from_pool = 1; + WARN_ON(!req->r_pages); + } +} + +/* + * initiate async writeback + */ +static int ceph_writepages_start(struct address_space *mapping, + struct writeback_control *wbc) +{ + struct inode *inode = mapping->host; + struct backing_dev_info *bdi = mapping->backing_dev_info; + struct ceph_inode_info *ci = ceph_inode(inode); + struct ceph_client *client = ceph_inode_to_client(inode); + pgoff_t index, start, end; + int range_whole = 0; + int should_loop = 1; + pgoff_t max_pages = 0, max_pages_ever = 0; + struct ceph_snap_context *snapc = NULL, *last_snapc = NULL; + struct pagevec pvec; + int done = 0; + int rc = 0; + unsigned wsize = 1 << inode->i_blkbits; + struct ceph_osd_request *req = NULL; + int do_sync; + u64 snap_size = 0; + + /* + * Include a 'sync' in the OSD request if this is a data + * integrity write (e.g., O_SYNC write or fsync()), or if our + * cap is being revoked. + */ + do_sync = wbc->sync_mode == WB_SYNC_ALL; + if (ceph_caps_revoking(ci, CEPH_CAP_FILE_BUFFER)) + do_sync = 1; + dout("writepages_start %p dosync=%d (mode=%s)\n", + inode, do_sync, + wbc->sync_mode == WB_SYNC_NONE ? "NONE" : + (wbc->sync_mode == WB_SYNC_ALL ? "ALL" : "HOLD")); + + client = ceph_inode_to_client(inode); + if (client->mount_state == CEPH_MOUNT_SHUTDOWN) { + pr_warning("writepage_start %p on forced umount\n", inode); + return -EIO; /* we're in a forced umount, don't write! */ + } + if (client->mount_args.wsize && client->mount_args.wsize < wsize) + wsize = client->mount_args.wsize; + if (wsize < PAGE_CACHE_SIZE) + wsize = PAGE_CACHE_SIZE; + max_pages_ever = wsize >> PAGE_CACHE_SHIFT; + + pagevec_init(&pvec, 0); + + /* ?? */ + if (wbc->nonblocking && bdi_write_congested(bdi)) { + dout(" writepages congested\n"); + wbc->encountered_congestion = 1; + goto out_final; + } + + /* where to start/end? */ + if (wbc->range_cyclic) { + start = mapping->writeback_index; /* Start from prev offset */ + end = -1; + dout(" cyclic, start at %lu\n", start); + } else { + start = wbc->range_start >> PAGE_CACHE_SHIFT; + end = wbc->range_end >> PAGE_CACHE_SHIFT; + if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX) + range_whole = 1; + should_loop = 0; + dout(" not cyclic, %lu to %lu\n", start, end); + } + index = start; + +retry: + /* find oldest snap context with dirty data */ + ceph_put_snap_context(snapc); + snapc = get_oldest_context(inode, &snap_size); + if (!snapc) { + /* hmm, why does writepages get called when there + is no dirty data? */ + dout(" no snap context with dirty data?\n"); + goto out; + } + dout(" oldest snapc is %p seq %lld (%d snaps)\n", + snapc, snapc->seq, snapc->num_snaps); + if (last_snapc && snapc != last_snapc) { + /* if we switched to a newer snapc, restart our scan at the + * start of the original file range. */ + dout(" snapc differs from last pass, restarting at %lu\n", + index); + index = start; + } + last_snapc = snapc; + + while (!done && index <= end) { + unsigned i; + int first; + pgoff_t next; + int pvec_pages, locked_pages; + struct page *page; + int want; + u64 offset, len; + struct ceph_osd_request_head *reqhead; + struct ceph_osd_op *op; + + next = 0; + locked_pages = 0; + max_pages = max_pages_ever; + +get_more_pages: + first = -1; + want = min(end - index, + min((pgoff_t)PAGEVEC_SIZE, + max_pages - (pgoff_t)locked_pages) - 1) + + 1; + pvec_pages = pagevec_lookup_tag(&pvec, mapping, &index, + PAGECACHE_TAG_DIRTY, + want); + dout("pagevec_lookup_tag got %d\n", pvec_pages); + if (!pvec_pages && !locked_pages) + break; + for (i = 0; i < pvec_pages && locked_pages < max_pages; i++) { + page = pvec.pages[i]; + dout("? %p idx %lu\n", page, page->index); + if (locked_pages == 0) + lock_page(page); /* first page */ + else if (!trylock_page(page)) + break; + + /* only dirty pages, or our accounting breaks */ + if (unlikely(!PageDirty(page)) || + unlikely(page->mapping != mapping)) { + dout("!dirty or !mapping %p\n", page); + unlock_page(page); + break; + } + if (!wbc->range_cyclic && page->index > end) { + dout("end of range %p\n", page); + done = 1; + unlock_page(page); + break; + } + if (next && (page->index != next)) { + dout("not consecutive %p\n", page); + unlock_page(page); + break; + } + if (wbc->sync_mode != WB_SYNC_NONE) { + dout("waiting on writeback %p\n", page); + wait_on_page_writeback(page); + } + if ((snap_size && page_offset(page) > snap_size) || + (!snap_size && + page_offset(page) > i_size_read(inode))) { + dout("%p page eof %llu\n", page, snap_size ? + snap_size : i_size_read(inode)); + done = 1; + unlock_page(page); + break; + } + if (PageWriteback(page)) { + dout("%p under writeback\n", page); + unlock_page(page); + break; + } + + /* only if matching snap context */ + if (snapc != (void *)page->private) { + dout("page snapc %p != oldest %p\n", + (void *)page->private, snapc); + unlock_page(page); + if (!locked_pages) + continue; /* keep looking for snap */ + break; + } + + if (!clear_page_dirty_for_io(page)) { + dout("%p !clear_page_dirty_for_io\n", page); + unlock_page(page); + break; + } + + /* ok */ + if (locked_pages == 0) { + /* prepare async write request */ + offset = page->index << PAGE_CACHE_SHIFT; + len = wsize; + req = ceph_osdc_new_request(&client->osdc, + &ci->i_layout, + ceph_vino(inode), + offset, &len, + CEPH_OSD_OP_WRITE, + CEPH_OSD_FLAG_WRITE | + CEPH_OSD_FLAG_ONDISK, + snapc, do_sync, + ci->i_truncate_seq, + ci->i_truncate_size, + &inode->i_mtime, true, 1); + max_pages = req->r_num_pages; + + alloc_page_vec(client, req); + req->r_callback = writepages_finish; + req->r_inode = inode; + req->r_wbc = wbc; + } + + /* note position of first page in pvec */ + if (first < 0) + first = i; + dout("%p will write page %p idx %lu\n", + inode, page, page->index); + set_page_writeback(page); + req->r_pages[locked_pages] = page; + locked_pages++; + next = page->index + 1; + } + + /* did we get anything? */ + if (!locked_pages) + goto release_pvec_pages; + if (i) { + int j; + BUG_ON(!locked_pages || first < 0); + + if (pvec_pages && i == pvec_pages && + locked_pages < max_pages) { + dout("reached end pvec, trying for more\n"); + pagevec_reinit(&pvec); + goto get_more_pages; + } + + /* shift unused pages over in the pvec... we + * will need to release them below. */ + for (j = i; j < pvec_pages; j++) { + dout(" pvec leftover page %p\n", + pvec.pages[j]); + pvec.pages[j-i+first] = pvec.pages[j]; + } + pvec.nr -= i-first; + } + + /* submit the write */ + offset = req->r_pages[0]->index << PAGE_CACHE_SHIFT; + len = min((snap_size ? snap_size : i_size_read(inode)) - offset, + (u64)locked_pages << PAGE_CACHE_SHIFT); + dout("writepages got %d pages at %llu~%llu\n", + locked_pages, offset, len); + + /* revise final length, page count */ + req->r_num_pages = locked_pages; + reqhead = req->r_request->front.iov_base; + op = (void *)(reqhead + 1); + op->extent.length = cpu_to_le64(len); + op->payload_len = cpu_to_le32(len); + req->r_request->hdr.data_len = cpu_to_le32(len); + + ceph_osdc_start_request(&client->osdc, req, true); + req = NULL; + + /* continue? */ + index = next; + wbc->nr_to_write -= locked_pages; + if (wbc->nr_to_write <= 0) + done = 1; + +release_pvec_pages: + dout("pagevec_release on %d pages (%p)\n", (int)pvec.nr, + pvec.nr ? pvec.pages[0] : NULL); + pagevec_release(&pvec); + + if (locked_pages && !done) + goto retry; + } + + if (should_loop && !done) { + /* more to do; loop back to beginning of file */ + dout("writepages looping back to beginning of file\n"); + should_loop = 0; + index = 0; + goto retry; + } + + if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0)) + mapping->writeback_index = index; + +out: + if (req) + ceph_osdc_put_request(req); + if (rc > 0) + rc = 0; /* vfs expects us to return 0 */ + ceph_put_snap_context(snapc); + dout("writepages done, rc = %d\n", rc); +out_final: + return rc; +} + + + +/* + * See if a given @snapc is either writeable, or already written. + */ +static int context_is_writeable_or_written(struct inode *inode, + struct ceph_snap_context *snapc) +{ + struct ceph_snap_context *oldest = get_oldest_context(inode, NULL); + return !oldest || snapc->seq <= oldest->seq; +} + +/* + * We are only allowed to write into/dirty the page if the page is + * clean, or already dirty within the same snap context. + */ +static int ceph_write_begin(struct file *file, struct address_space *mapping, + loff_t pos, unsigned len, unsigned flags, + struct page **pagep, void **fsdata) +{ + struct inode *inode = file->f_dentry->d_inode; + struct ceph_inode_info *ci = ceph_inode(inode); + struct ceph_mds_client *mdsc = &ceph_inode_to_client(inode)->mdsc; + struct page *page; + pgoff_t index = pos >> PAGE_CACHE_SHIFT; + loff_t page_off = pos & PAGE_CACHE_MASK; + int pos_in_page = pos & ~PAGE_CACHE_MASK; + int end_in_page = pos_in_page + len; + loff_t i_size; + struct ceph_snap_context *snapc; + int r; + + /* get a page*/ +retry: + page = grab_cache_page_write_begin(mapping, index, 0); + if (!page) + return -ENOMEM; + *pagep = page; + + dout("write_begin file %p inode %p page %p %d~%d\n", file, + inode, page, (int)pos, (int)len); + +retry_locked: + /* writepages currently holds page lock, but if we change that later, */ + wait_on_page_writeback(page); + + /* check snap context */ + BUG_ON(!ci->i_snap_realm); + down_read(&mdsc->snap_rwsem); + BUG_ON(!ci->i_snap_realm->cached_context); + if (page->private && + (void *)page->private != ci->i_snap_realm->cached_context) { + /* + * this page is already dirty in another (older) snap + * context! is it writeable now? + */ + snapc = get_oldest_context(inode, NULL); + up_read(&mdsc->snap_rwsem); + + if (snapc != (void *)page->private) { + dout(" page %p snapc %p not current or oldest\n", + page, (void *)page->private); + /* + * queue for writeback, and wait for snapc to + * be writeable or written + */ + snapc = ceph_get_snap_context((void *)page->private); + unlock_page(page); + if (ceph_queue_writeback(inode)) + igrab(inode); + wait_event_interruptible(ci->i_cap_wq, + context_is_writeable_or_written(inode, snapc)); + ceph_put_snap_context(snapc); + goto retry; + } + + /* yay, writeable, do it now (without dropping page lock) */ + dout(" page %p snapc %p not current, but oldest\n", + page, snapc); + if (!clear_page_dirty_for_io(page)) + goto retry_locked; + r = writepage_nounlock(page, NULL); + if (r < 0) + goto fail_nosnap; + goto retry_locked; + } + + if (PageUptodate(page)) { + dout(" page %p already uptodate\n", page); + return 0; + } + + /* full page? */ + if (pos_in_page == 0 && len == PAGE_CACHE_SIZE) + return 0; + + /* past end of file? */ + i_size = inode->i_size; /* caller holds i_mutex */ + + if (i_size + len > inode->i_sb->s_maxbytes) { + /* file is too big */ + r = -EINVAL; + goto fail; + } + + if (page_off >= i_size || + (pos_in_page == 0 && (pos+len) >= i_size && + end_in_page - pos_in_page != PAGE_CACHE_SIZE)) { + dout(" zeroing %p 0 - %d and %d - %d\n", + page, pos_in_page, end_in_page, (int)PAGE_CACHE_SIZE); + zero_user_segments(page, + 0, pos_in_page, + end_in_page, PAGE_CACHE_SIZE); + return 0; + } + + /* we need to read it. */ + up_read(&mdsc->snap_rwsem); + r = readpage_nounlock(file, page); + if (r < 0) + goto fail_nosnap; + goto retry_locked; + +fail: + up_read(&mdsc->snap_rwsem); +fail_nosnap: + unlock_page(page); + return r; +} + +/* + * we don't do anything in here that simple_write_end doesn't do + * except adjust dirty page accounting and drop read lock on + * mdsc->snap_rwsem. + */ +static int ceph_write_end(struct file *file, struct address_space *mapping, + loff_t pos, unsigned len, unsigned copied, + struct page *page, void *fsdata) +{ + struct inode *inode = file->f_dentry->d_inode; + struct ceph_mds_client *mdsc = &ceph_inode_to_client(inode)->mdsc; + unsigned from = pos & (PAGE_CACHE_SIZE - 1); + int check_cap = 0; + + dout("write_end file %p inode %p page %p %d~%d (%d)\n", file, + inode, page, (int)pos, (int)copied, (int)len); + + /* zero the stale part of the page if we did a short copy */ + if (copied < len) + zero_user_segment(page, from+copied, len); + + /* did file size increase? */ + /* (no need for i_size_read(); we caller holds i_mutex */ + if (pos+copied > inode->i_size) + check_cap = ceph_inode_set_size(inode, pos+copied); + + if (!PageUptodate(page)) + SetPageUptodate(page); + + set_page_dirty(page); + + unlock_page(page); + up_read(&mdsc->snap_rwsem); + page_cache_release(page); + + if (check_cap) + ceph_check_caps(ceph_inode(inode), CHECK_CAPS_AUTHONLY, NULL); + + return copied; +} + +/* + * we set .direct_IO to indicate direct io is supported, but since we + * intercept O_DIRECT reads and writes early, this function should + * never get called. + */ +static ssize_t ceph_direct_io(int rw, struct kiocb *iocb, + const struct iovec *iov, + loff_t pos, unsigned long nr_segs) +{ + WARN_ON(1); + return -EINVAL; +} + +const struct address_space_operations ceph_aops = { + .readpage = ceph_readpage, + .readpages = ceph_readpages, + .writepage = ceph_writepage, + .writepages = ceph_writepages_start, + .write_begin = ceph_write_begin, + .write_end = ceph_write_end, + .set_page_dirty = ceph_set_page_dirty, + .invalidatepage = ceph_invalidatepage, + .releasepage = ceph_releasepage, + .direct_IO = ceph_direct_io, +}; + + +/* + * vm ops + */ + +/* + * Reuse write_begin here for simplicity. + */ +static int ceph_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) +{ + struct inode *inode = vma->vm_file->f_dentry->d_inode; + struct page *page = vmf->page; + struct ceph_mds_client *mdsc = &ceph_inode_to_client(inode)->mdsc; + loff_t off = page->index << PAGE_CACHE_SHIFT; + loff_t size, len; + struct page *locked_page = NULL; + void *fsdata = NULL; + int ret; + + size = i_size_read(inode); + if (off + PAGE_CACHE_SIZE <= size) + len = PAGE_CACHE_SIZE; + else + len = size & ~PAGE_CACHE_MASK; + + dout("page_mkwrite %p %llu~%llu page %p idx %lu\n", inode, + off, len, page, page->index); + ret = ceph_write_begin(vma->vm_file, inode->i_mapping, off, len, 0, + &locked_page, &fsdata); + WARN_ON(page != locked_page); + if (!ret) { + /* + * doing the following, instead of calling + * ceph_write_end. Note that we keep the + * page locked + */ + set_page_dirty(page); + up_read(&mdsc->snap_rwsem); + page_cache_release(page); + ret = VM_FAULT_LOCKED; + } else { + ret = VM_FAULT_SIGBUS; + } + dout("page_mkwrite %p %llu~%llu = %d\n", inode, off, len, ret); + return ret; +} + +static struct vm_operations_struct ceph_vmops = { + .fault = filemap_fault, + .page_mkwrite = ceph_page_mkwrite, +}; + +int ceph_mmap(struct file *file, struct vm_area_struct *vma) +{ + struct address_space *mapping = file->f_mapping; + + if (!mapping->a_ops->readpage) + return -ENOEXEC; + file_accessed(file); + vma->vm_ops = &ceph_vmops; + vma->vm_flags |= VM_CAN_NONLINEAR; + return 0; +} -- cgit v1.2.2 From 6b8051855d983db8480ff1ea1b02ef2b49203c22 Mon Sep 17 00:00:00 2001 From: Sage Weil Date: Tue, 27 Oct 2009 11:50:50 -0700 Subject: ceph: allocate and parse mount args before client instance This simplifies much of the error handling during mount. It also means that we have the mount args before client creation, and we can initialize based on those options. Signed-off-by: Sage Weil --- fs/ceph/addr.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'fs/ceph/addr.c') diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c index c7d673ffe023..bf535815592d 100644 --- a/fs/ceph/addr.c +++ b/fs/ceph/addr.c @@ -600,8 +600,8 @@ static int ceph_writepages_start(struct address_space *mapping, pr_warning("writepage_start %p on forced umount\n", inode); return -EIO; /* we're in a forced umount, don't write! */ } - if (client->mount_args.wsize && client->mount_args.wsize < wsize) - wsize = client->mount_args.wsize; + if (client->mount_args->wsize && client->mount_args->wsize < wsize) + wsize = client->mount_args->wsize; if (wsize < PAGE_CACHE_SIZE) wsize = PAGE_CACHE_SIZE; max_pages_ever = wsize >> PAGE_CACHE_SHIFT; -- cgit v1.2.2 From dbd646a851713bec5bfff40ecf624b2e78518fe5 Mon Sep 17 00:00:00 2001 From: Yehuda Sadeh Date: Wed, 16 Dec 2009 14:51:06 -0800 Subject: ceph: writepage grabs and releases inode Fixes a deadlock that is triggered due to kswapd, while the page was locked and the iput couldn't tear down the address space. Signed-off-by: Yehuda Sadeh --- fs/ceph/addr.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'fs/ceph/addr.c') diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c index bf535815592d..d0cdceb0b90b 100644 --- a/fs/ceph/addr.c +++ b/fs/ceph/addr.c @@ -448,8 +448,13 @@ out: static int ceph_writepage(struct page *page, struct writeback_control *wbc) { - int err = writepage_nounlock(page, wbc); + int err; + struct inode *inode = page->mapping->host; + BUG_ON(!inode); + igrab(inode); + err = writepage_nounlock(page, wbc); unlock_page(page); + iput(inode); return err; } -- cgit v1.2.2 From 2baba25019ec564cd247af74013873d69a0b8190 Mon Sep 17 00:00:00 2001 From: Yehuda Sadeh Date: Fri, 18 Dec 2009 13:51:57 -0800 Subject: ceph: writeback congestion control Set bdi congestion bit when amount of write data in flight exceeds adjustable threshold. Signed-off-by: Yehuda Sadeh Signed-off-by: Sage Weil --- fs/ceph/addr.c | 35 +++++++++++++++++++++++++++++++++-- 1 file changed, 33 insertions(+), 2 deletions(-) (limited to 'fs/ceph/addr.c') diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c index d0cdceb0b90b..a6850a14038e 100644 --- a/fs/ceph/addr.c +++ b/fs/ceph/addr.c @@ -47,6 +47,12 @@ * accounting is preserved. */ +#define CONGESTION_ON_THRESH(congestion_kb) (congestion_kb >> (PAGE_SHIFT-10)) +#define CONGESTION_OFF_THRESH(congestion_kb) \ + (CONGESTION_ON_THRESH(congestion_kb) - \ + (CONGESTION_ON_THRESH(congestion_kb) >> 2)) + + /* * Dirty a page. Optimistically adjust accounting, on the assumption @@ -377,6 +383,7 @@ static int writepage_nounlock(struct page *page, struct writeback_control *wbc) { struct inode *inode; struct ceph_inode_info *ci; + struct ceph_client *client; struct ceph_osd_client *osdc; loff_t page_off = page->index << PAGE_CACHE_SHIFT; int len = PAGE_CACHE_SIZE; @@ -384,6 +391,7 @@ static int writepage_nounlock(struct page *page, struct writeback_control *wbc) int err = 0; struct ceph_snap_context *snapc; u64 snap_size = 0; + long writeback_stat; dout("writepage %p idx %lu\n", page, page->index); @@ -393,7 +401,8 @@ static int writepage_nounlock(struct page *page, struct writeback_control *wbc) } inode = page->mapping->host; ci = ceph_inode(inode); - osdc = &ceph_inode_to_client(inode)->osdc; + client = ceph_inode_to_client(inode); + osdc = &client->osdc; /* verify this is a writeable snap context */ snapc = (void *)page->private; @@ -420,6 +429,11 @@ static int writepage_nounlock(struct page *page, struct writeback_control *wbc) dout("writepage %p page %p index %lu on %llu~%u\n", inode, page, page->index, page_off, len); + writeback_stat = atomic_long_inc_return(&client->writeback_count); + if (writeback_stat > + CONGESTION_ON_THRESH(client->mount_args->congestion_kb)) + set_bdi_congested(&client->backing_dev_info, BLK_RW_ASYNC); + set_page_writeback(page); err = ceph_osdc_writepages(osdc, ceph_vino(inode), &ci->i_layout, snapc, @@ -499,6 +513,8 @@ static void writepages_finish(struct ceph_osd_request *req, struct writeback_control *wbc = req->r_wbc; __s32 rc = -EIO; u64 bytes = 0; + struct ceph_client *client = ceph_inode_to_client(inode); + long writeback_stat; /* parse reply */ replyhead = msg->front.iov_base; @@ -524,6 +540,13 @@ static void writepages_finish(struct ceph_osd_request *req, BUG_ON(!page); WARN_ON(!PageUptodate(page)); + writeback_stat = + atomic_long_dec_return(&client->writeback_count); + if (writeback_stat < + CONGESTION_OFF_THRESH(client->mount_args->congestion_kb)) + clear_bdi_congested(&client->backing_dev_info, + BLK_RW_ASYNC); + if (i >= wrote) { dout("inode %p skipping page %p\n", inode, page); wbc->pages_skipped++; @@ -666,6 +689,7 @@ retry: u64 offset, len; struct ceph_osd_request_head *reqhead; struct ceph_osd_op *op; + long writeback_stat; next = 0; locked_pages = 0; @@ -773,6 +797,12 @@ get_more_pages: first = i; dout("%p will write page %p idx %lu\n", inode, page, page->index); + + writeback_stat = atomic_long_inc_return(&client->writeback_count); + if (writeback_stat > CONGESTION_ON_THRESH(client->mount_args->congestion_kb)) { + set_bdi_congested(&client->backing_dev_info, BLK_RW_ASYNC); + } + set_page_writeback(page); req->r_pages[locked_pages] = page; locked_pages++; @@ -998,7 +1028,8 @@ static int ceph_write_end(struct file *file, struct address_space *mapping, struct page *page, void *fsdata) { struct inode *inode = file->f_dentry->d_inode; - struct ceph_mds_client *mdsc = &ceph_inode_to_client(inode)->mdsc; + struct ceph_client *client = ceph_inode_to_client(inode); + struct ceph_mds_client *mdsc = &client->mdsc; unsigned from = pos & (PAGE_CACHE_SIZE - 1); int check_cap = 0; -- cgit v1.2.2 From ec7384ec23dc5a9ea8733e90438e16b6066bfe1b Mon Sep 17 00:00:00 2001 From: Julia Lawall Date: Wed, 20 Jan 2010 15:16:41 -0800 Subject: ceph: remove duplicate variable initialization The variable client is initialized twice to the same (side effect-free) expression. Drop one initialization. A simplified version of the semantic match that finds this problem is: (http://coccinelle.lip6.fr/) // @forall@ idexpression *x; identifier f!=ERR_PTR; @@ x = f(...) ... when != x ( x = f(...,<+...x...+>,...) | * x = f(...) ) // Signed-off-by: Julia Lawall Signed-off-by: Sage Weil --- fs/ceph/addr.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs/ceph/addr.c') diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c index a6850a14038e..a3bd9deb555c 100644 --- a/fs/ceph/addr.c +++ b/fs/ceph/addr.c @@ -596,7 +596,7 @@ static int ceph_writepages_start(struct address_space *mapping, struct inode *inode = mapping->host; struct backing_dev_info *bdi = mapping->backing_dev_info; struct ceph_inode_info *ci = ceph_inode(inode); - struct ceph_client *client = ceph_inode_to_client(inode); + struct ceph_client *client; pgoff_t index, start, end; int range_whole = 0; int should_loop = 1; -- cgit v1.2.2 From 79788c698b290426320e60374ed1324e4b5c69eb Mon Sep 17 00:00:00 2001 From: Sage Weil Date: Tue, 2 Feb 2010 16:34:04 -0800 Subject: ceph: release all pages after successful osd write response We release all the pages, even if the osd response was different than the number of pages written. This could only happen due to truncation that arrives the osd in different order, for which we want the pages released anyway. Signed-off-by: Yehuda Sadeh Signed-off-by: Sage Weil --- fs/ceph/addr.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) (limited to 'fs/ceph/addr.c') diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c index a3bd9deb555c..8065dc92c611 100644 --- a/fs/ceph/addr.c +++ b/fs/ceph/addr.c @@ -524,9 +524,13 @@ static void writepages_finish(struct ceph_osd_request *req, bytes = le64_to_cpu(op->extent.length); if (rc >= 0) { - wrote = (bytes + (offset & ~PAGE_CACHE_MASK) + ~PAGE_CACHE_MASK) - >> PAGE_CACHE_SHIFT; - WARN_ON(wrote != req->r_num_pages); + /* + * Assume we wrote the pages we originally sent. The + * osd might reply with fewer pages if our writeback + * raced with a truncation and was adjusted at the osd, + * so don't believe the reply. + */ + wrote = req->r_num_pages; } else { wrote = 0; mapping_set_error(mapping, rc); -- cgit v1.2.2 From b056c8769d1da6a6a80ce780a4b8957b70434a41 Mon Sep 17 00:00:00 2001 From: Yehuda Sadeh Date: Wed, 3 Feb 2010 10:47:48 -0800 Subject: ceph: remove unused variable Signed-off-by: Yehuda Sadeh Signed-off-by: Sage Weil --- fs/ceph/addr.c | 1 - 1 file changed, 1 deletion(-) (limited to 'fs/ceph/addr.c') diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c index 8065dc92c611..92f482150742 100644 --- a/fs/ceph/addr.c +++ b/fs/ceph/addr.c @@ -505,7 +505,6 @@ static void writepages_finish(struct ceph_osd_request *req, struct ceph_osd_op *op; struct ceph_inode_info *ci = ceph_inode(inode); unsigned wrote; - loff_t offset = req->r_pages[0]->index << PAGE_CACHE_SHIFT; struct page *page; int i; struct ceph_snap_context *snapc = req->r_snapc; -- cgit v1.2.2 From 4af6b2257ee0eb8f4bf3b1dc8acb643c0e8a887f Mon Sep 17 00:00:00 2001 From: Yehuda Sadeh Date: Tue, 9 Feb 2010 11:02:51 -0800 Subject: ceph: refactor ceph_write_begin, fix ceph_page_mkwrite Originally ceph_page_mkwrite called ceph_write_begin, hoping that the returned locked page would be the page that it was requested to mkwrite. Factored out relevant part of ceph_page_mkwrite and we lock the right page anyway. Signed-off-by: Yehuda Sadeh Signed-off-by: Sage Weil --- fs/ceph/addr.c | 80 +++++++++++++++++++++++++++++++++++++--------------------- 1 file changed, 51 insertions(+), 29 deletions(-) (limited to 'fs/ceph/addr.c') diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c index 92f482150742..89c5ff3b59d5 100644 --- a/fs/ceph/addr.c +++ b/fs/ceph/addr.c @@ -907,15 +907,13 @@ static int context_is_writeable_or_written(struct inode *inode, * We are only allowed to write into/dirty the page if the page is * clean, or already dirty within the same snap context. */ -static int ceph_write_begin(struct file *file, struct address_space *mapping, - loff_t pos, unsigned len, unsigned flags, - struct page **pagep, void **fsdata) +static int ceph_update_writeable_page(struct file *file, + loff_t pos, unsigned len, + struct page *page) { struct inode *inode = file->f_dentry->d_inode; struct ceph_inode_info *ci = ceph_inode(inode); struct ceph_mds_client *mdsc = &ceph_inode_to_client(inode)->mdsc; - struct page *page; - pgoff_t index = pos >> PAGE_CACHE_SHIFT; loff_t page_off = pos & PAGE_CACHE_MASK; int pos_in_page = pos & ~PAGE_CACHE_MASK; int end_in_page = pos_in_page + len; @@ -923,16 +921,6 @@ static int ceph_write_begin(struct file *file, struct address_space *mapping, struct ceph_snap_context *snapc; int r; - /* get a page*/ -retry: - page = grab_cache_page_write_begin(mapping, index, 0); - if (!page) - return -ENOMEM; - *pagep = page; - - dout("write_begin file %p inode %p page %p %d~%d\n", file, - inode, page, (int)pos, (int)len); - retry_locked: /* writepages currently holds page lock, but if we change that later, */ wait_on_page_writeback(page); @@ -964,7 +952,7 @@ retry_locked: wait_event_interruptible(ci->i_cap_wq, context_is_writeable_or_written(inode, snapc)); ceph_put_snap_context(snapc); - goto retry; + return -EAGAIN; } /* yay, writeable, do it now (without dropping page lock) */ @@ -1021,6 +1009,35 @@ fail_nosnap: return r; } +/* + * We are only allowed to write into/dirty the page if the page is + * clean, or already dirty within the same snap context. + */ +static int ceph_write_begin(struct file *file, struct address_space *mapping, + loff_t pos, unsigned len, unsigned flags, + struct page **pagep, void **fsdata) +{ + struct inode *inode = file->f_dentry->d_inode; + struct page *page; + pgoff_t index = pos >> PAGE_CACHE_SHIFT; + int r; + + do { + /* get a page*/ + page = grab_cache_page_write_begin(mapping, index, 0); + if (!page) + return -ENOMEM; + *pagep = page; + + dout("write_begin file %p inode %p page %p %d~%d\n", file, + inode, page, (int)pos, (int)len); + + r = ceph_update_writeable_page(file, pos, len, page); + } while (r == -EAGAIN); + + return r; +} + /* * we don't do anything in here that simple_write_end doesn't do * except adjust dirty page accounting and drop read lock on @@ -1104,8 +1121,6 @@ static int ceph_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) struct ceph_mds_client *mdsc = &ceph_inode_to_client(inode)->mdsc; loff_t off = page->index << PAGE_CACHE_SHIFT; loff_t size, len; - struct page *locked_page = NULL; - void *fsdata = NULL; int ret; size = i_size_read(inode); @@ -1116,23 +1131,30 @@ static int ceph_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) dout("page_mkwrite %p %llu~%llu page %p idx %lu\n", inode, off, len, page, page->index); - ret = ceph_write_begin(vma->vm_file, inode->i_mapping, off, len, 0, - &locked_page, &fsdata); - WARN_ON(page != locked_page); - if (!ret) { - /* - * doing the following, instead of calling - * ceph_write_end. Note that we keep the - * page locked - */ + + lock_page(page); + + ret = VM_FAULT_NOPAGE; + if ((off > size) || + (page->mapping != inode->i_mapping)) + goto out; + + ret = ceph_update_writeable_page(vma->vm_file, off, len, page); + if (ret == 0) { + /* success. we'll keep the page locked. */ set_page_dirty(page); up_read(&mdsc->snap_rwsem); - page_cache_release(page); ret = VM_FAULT_LOCKED; } else { - ret = VM_FAULT_SIGBUS; + if (ret == -ENOMEM) + ret = VM_FAULT_OOM; + else + ret = VM_FAULT_SIGBUS; } +out: dout("page_mkwrite %p %llu~%llu = %d\n", inode, off, len, ret); + if (ret != VM_FAULT_LOCKED) + unlock_page(page); return ret; } -- cgit v1.2.2 From 3c6f6b79a64db7f1c7abf09d693db3b0066784fb Mon Sep 17 00:00:00 2001 From: Sage Weil Date: Tue, 9 Feb 2010 15:24:44 -0800 Subject: ceph: cleanup async writeback, truncation, invalidate helpers Grab inode ref in helper. Make work functions static, with consistent naming. Signed-off-by: Sage Weil --- fs/ceph/addr.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'fs/ceph/addr.c') diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c index 89c5ff3b59d5..71f5ad1c1e26 100644 --- a/fs/ceph/addr.c +++ b/fs/ceph/addr.c @@ -947,8 +947,7 @@ retry_locked: */ snapc = ceph_get_snap_context((void *)page->private); unlock_page(page); - if (ceph_queue_writeback(inode)) - igrab(inode); + ceph_queue_writeback(inode); wait_event_interruptible(ci->i_cap_wq, context_is_writeable_or_written(inode, snapc)); ceph_put_snap_context(snapc); -- cgit v1.2.2 From e63dc5c780ba32d6d8b3662eecce2b8d96489b41 Mon Sep 17 00:00:00 2001 From: Yehuda Sadeh Date: Fri, 19 Feb 2010 00:07:01 +0000 Subject: ceph: remove page upon writeback completion if lost cache cap This page should have been removed earlier when the cache cap was revoked, but a writeback was in flight, so it was skipped. We truncate it here just as the writeback finishes, while it's still locked. Signed-off-by: Yehuda Sadeh Signed-off-by: Sage Weil --- fs/ceph/addr.c | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'fs/ceph/addr.c') diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c index 71f5ad1c1e26..25360d517d1b 100644 --- a/fs/ceph/addr.c +++ b/fs/ceph/addr.c @@ -514,6 +514,7 @@ static void writepages_finish(struct ceph_osd_request *req, u64 bytes = 0; struct ceph_client *client = ceph_inode_to_client(inode); long writeback_stat; + unsigned issued = __ceph_caps_issued(ci, NULL); /* parse reply */ replyhead = msg->front.iov_base; @@ -559,6 +560,16 @@ static void writepages_finish(struct ceph_osd_request *req, ceph_put_snap_context(snapc); dout("unlocking %d %p\n", i, page); end_page_writeback(page); + + /* + * We lost the cache cap, need to truncate the page before + * it is unlocked, otherwise we'd truncate it later in the + * page truncation thread, possibly losing some data that + * raced its way in + */ + if ((issued & CEPH_CAP_FILE_CACHE) == 0) + generic_error_remove_page(inode->i_mapping, page); + unlock_page(page); } dout("%p wrote+cleaned %d pages\n", inode, wrote); -- cgit v1.2.2 From 4ce1e9adabbad8f2c45ceeeb6de56cc368484297 Mon Sep 17 00:00:00 2001 From: Alexander Beregalov Date: Mon, 22 Feb 2010 17:17:44 +0300 Subject: ceph: move dereference after NULL test Signed-off-by: Alexander Beregalov Signed-off-by: Sage Weil --- fs/ceph/addr.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'fs/ceph/addr.c') diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c index 25360d517d1b..23bb0ceabe31 100644 --- a/fs/ceph/addr.c +++ b/fs/ceph/addr.c @@ -144,7 +144,7 @@ static int ceph_set_page_dirty(struct page *page) */ static void ceph_invalidatepage(struct page *page, unsigned long offset) { - struct inode *inode = page->mapping->host; + struct inode *inode; struct ceph_inode_info *ci; struct ceph_snap_context *snapc = (void *)page->private; @@ -153,6 +153,8 @@ static void ceph_invalidatepage(struct page *page, unsigned long offset) BUG_ON(!PagePrivate(page)); BUG_ON(!page->mapping); + inode = page->mapping->host; + /* * We can get non-dirty pages here due to races between * set_page_dirty and truncate_complete_page; just spit out a -- cgit v1.2.2