addr.c 49.0 KB
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#include <linux/ceph/ceph_debug.h>
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#include <linux/backing-dev.h>
#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/pagemap.h>
#include <linux/writeback.h>	/* generic_writepages */
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#include <linux/slab.h>
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#include <linux/pagevec.h>
#include <linux/task_io_accounting_ops.h>

#include "super.h"
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#include "mds_client.h"
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#include "cache.h"
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#include <linux/ceph/osd_client.h>
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/*
 * 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
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 * count dirty pages on the inode.  In the absence of snapshots,
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 * 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.
 */

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#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))

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static inline struct ceph_snap_context *page_snap_context(struct page *page)
{
	if (PagePrivate(page))
		return (void *)page->private;
	return NULL;
}
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/*
 * 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;
	struct ceph_snap_context *snapc;
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	int ret;
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	if (unlikely(!mapping))
		return !TestSetPageDirty(page);

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	if (PageDirty(page)) {
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		dout("%p set_page_dirty %p idx %lu -- already dirty\n",
		     mapping->host, page, page->index);
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		BUG_ON(!PagePrivate(page));
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		return 0;
	}

	inode = mapping->host;
	ci = ceph_inode(inode);

	/* dirty the head */
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	spin_lock(&ci->i_ceph_lock);
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	BUG_ON(ci->i_wr_ref == 0); // caller should hold Fw reference
	if (__ceph_have_pending_cap_snap(ci)) {
		struct ceph_cap_snap *capsnap =
				list_last_entry(&ci->i_cap_snaps,
						struct ceph_cap_snap,
						ci_item);
		snapc = ceph_get_snap_context(capsnap->context);
		capsnap->dirty_pages++;
	} else {
		BUG_ON(!ci->i_head_snapc);
		snapc = ceph_get_snap_context(ci->i_head_snapc);
		++ci->i_wrbuffer_ref_head;
	}
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	if (ci->i_wrbuffer_ref == 0)
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		ihold(inode);
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	++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);
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	spin_unlock(&ci->i_ceph_lock);
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	/*
	 * Reference snap context in page->private.  Also set
	 * PagePrivate so that we get invalidatepage callback.
	 */
	BUG_ON(PagePrivate(page));
	page->private = (unsigned long)snapc;
	SetPagePrivate(page);
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	ret = __set_page_dirty_nobuffers(page);
	WARN_ON(!PageLocked(page));
	WARN_ON(!page->mapping);
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	return ret;
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}

/*
 * 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.
 */
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static void ceph_invalidatepage(struct page *page, unsigned int offset,
				unsigned int length)
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{
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	struct inode *inode;
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	struct ceph_inode_info *ci;
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	struct ceph_snap_context *snapc = page_snap_context(page);
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	inode = page->mapping->host;
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	ci = ceph_inode(inode);

	if (offset != 0 || length != PAGE_CACHE_SIZE) {
		dout("%p invalidatepage %p idx %lu partial dirty page %u~%u\n",
		     inode, page, page->index, offset, length);
		return;
	}
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	ceph_invalidate_fscache_page(inode, page);

	if (!PagePrivate(page))
		return;

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	/*
	 * 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);

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	ClearPageChecked(page);
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	dout("%p invalidatepage %p idx %lu full dirty page\n",
	     inode, page, page->index);

	ceph_put_wrbuffer_cap_refs(ci, 1, snapc);
	ceph_put_snap_context(snapc);
	page->private = 0;
	ClearPagePrivate(page);
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}

static int ceph_releasepage(struct page *page, gfp_t g)
{
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	dout("%p releasepage %p idx %lu\n", page->mapping->host,
	     page, page->index);
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	WARN_ON(PageDirty(page));
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	/* Can we release the page from the cache? */
	if (!ceph_release_fscache_page(page, g))
		return 0;

	return !PagePrivate(page);
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}

/*
 * read a single page, without unlocking it.
 */
static int readpage_nounlock(struct file *filp, struct page *page)
{
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	struct inode *inode = file_inode(filp);
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	struct ceph_inode_info *ci = ceph_inode(inode);
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	struct ceph_osd_client *osdc =
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		&ceph_inode_to_client(inode)->client->osdc;
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	int err = 0;
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	u64 off = page_offset(page);
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	u64 len = PAGE_CACHE_SIZE;

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	if (off >= i_size_read(inode)) {
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		zero_user_segment(page, 0, PAGE_CACHE_SIZE);
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		SetPageUptodate(page);
		return 0;
	}
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	if (ci->i_inline_version != CEPH_INLINE_NONE) {
		/*
		 * Uptodate inline data should have been added
		 * into page cache while getting Fcr caps.
		 */
		if (off == 0)
			return -EINVAL;
		zero_user_segment(page, 0, PAGE_CACHE_SIZE);
		SetPageUptodate(page);
		return 0;
	}
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	err = ceph_readpage_from_fscache(inode, page);
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	if (err == 0)
		goto out;

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	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,
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				  off, &len,
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				  ci->i_truncate_seq, ci->i_truncate_size,
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				  &page, 1, 0);
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	if (err == -ENOENT)
		err = 0;
	if (err < 0) {
		SetPageError(page);
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		ceph_fscache_readpage_cancel(inode, page);
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		goto out;
	}
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	if (err < PAGE_CACHE_SIZE)
		/* zero fill remainder of page */
		zero_user_segment(page, err, PAGE_CACHE_SIZE);
	else
		flush_dcache_page(page);
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	SetPageUptodate(page);
	ceph_readpage_to_fscache(inode, page);
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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;
}

/*
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 * Finish an async read(ahead) op.
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 */
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static void finish_read(struct ceph_osd_request *req, struct ceph_msg *msg)
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{
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	struct inode *inode = req->r_inode;
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	struct ceph_osd_data *osd_data;
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	int rc = req->r_result;
	int bytes = le32_to_cpu(msg->hdr.data_len);
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	int num_pages;
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	int i;
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	dout("finish_read %p req %p rc %d bytes %d\n", inode, req, rc, bytes);

	/* unlock all pages, zeroing any data we didn't read */
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	osd_data = osd_req_op_extent_osd_data(req, 0);
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	BUG_ON(osd_data->type != CEPH_OSD_DATA_TYPE_PAGES);
	num_pages = calc_pages_for((u64)osd_data->alignment,
					(u64)osd_data->length);
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	for (i = 0; i < num_pages; i++) {
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		struct page *page = osd_data->pages[i];
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		if (rc < 0 && rc != -ENOENT)
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			goto unlock;
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		if (bytes < (int)PAGE_CACHE_SIZE) {
			/* zero (remainder of) page */
			int s = bytes < 0 ? 0 : bytes;
			zero_user_segment(page, s, PAGE_CACHE_SIZE);
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		}
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 		dout("finish_read %p uptodate %p idx %lu\n", inode, page,
		     page->index);
		flush_dcache_page(page);
		SetPageUptodate(page);
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		ceph_readpage_to_fscache(inode, page);
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unlock:
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		unlock_page(page);
		page_cache_release(page);
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		bytes -= PAGE_CACHE_SIZE;
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	}
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	kfree(osd_data->pages);
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}

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static void ceph_unlock_page_vector(struct page **pages, int num_pages)
{
	int i;

	for (i = 0; i < num_pages; i++)
		unlock_page(pages[i]);
}

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/*
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 * start an async read(ahead) operation.  return nr_pages we submitted
 * a read for on success, or negative error code.
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 */
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static int start_read(struct inode *inode, struct list_head *page_list, int max)
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{
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	struct ceph_osd_client *osdc =
		&ceph_inode_to_client(inode)->client->osdc;
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	struct ceph_inode_info *ci = ceph_inode(inode);
	struct page *page = list_entry(page_list->prev, struct page, lru);
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	struct ceph_vino vino;
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	struct ceph_osd_request *req;
	u64 off;
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	u64 len;
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	int i;
	struct page **pages;
	pgoff_t next_index;
	int nr_pages = 0;
	int ret;
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	off = (u64) page_offset(page);
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	/* count pages */
	next_index = page->index;
	list_for_each_entry_reverse(page, page_list, lru) {
		if (page->index != next_index)
			break;
		nr_pages++;
		next_index++;
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		if (max && nr_pages == max)
			break;
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	}
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	len = nr_pages << PAGE_CACHE_SHIFT;
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	dout("start_read %p nr_pages %d is %lld~%lld\n", inode, nr_pages,
	     off, len);
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	vino = ceph_vino(inode);
	req = ceph_osdc_new_request(osdc, &ci->i_layout, vino, off, &len,
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				    0, 1, CEPH_OSD_OP_READ,
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				    CEPH_OSD_FLAG_READ, NULL,
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				    ci->i_truncate_seq, ci->i_truncate_size,
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				    false);
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	if (IS_ERR(req))
		return PTR_ERR(req);
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	/* build page vector */
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	nr_pages = calc_pages_for(0, len);
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	pages = kmalloc(sizeof(*pages) * nr_pages, GFP_KERNEL);
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	ret = -ENOMEM;
	if (!pages)
		goto out;
	for (i = 0; i < nr_pages; ++i) {
		page = list_entry(page_list->prev, struct page, lru);
		BUG_ON(PageLocked(page));
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		list_del(&page->lru);
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 		dout("start_read %p adding %p idx %lu\n", inode, page,
		     page->index);
		if (add_to_page_cache_lru(page, &inode->i_data, page->index,
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					  GFP_KERNEL)) {
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			ceph_fscache_uncache_page(inode, page);
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			page_cache_release(page);
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			dout("start_read %p add_to_page_cache failed %p\n",
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			     inode, page);
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			nr_pages = i;
			goto out_pages;
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		}
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		pages[i] = page;
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	}
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	osd_req_op_extent_osd_data_pages(req, 0, pages, len, 0, false, false);
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	req->r_callback = finish_read;
	req->r_inode = inode;

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	ceph_osdc_build_request(req, off, NULL, vino.snap, NULL);
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	dout("start_read %p starting %p %lld~%lld\n", inode, req, off, len);
	ret = ceph_osdc_start_request(osdc, req, false);
	if (ret < 0)
		goto out_pages;
	ceph_osdc_put_request(req);
	return nr_pages;

out_pages:
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	ceph_unlock_page_vector(pages, nr_pages);
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	ceph_release_page_vector(pages, nr_pages);
out:
	ceph_osdc_put_request(req);
	return ret;
}
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/*
 * 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)
{
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	struct inode *inode = file_inode(file);
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	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
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	int rc = 0;
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	int max = 0;

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	if (ceph_inode(inode)->i_inline_version != CEPH_INLINE_NONE)
		return -EINVAL;

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	rc = ceph_readpages_from_fscache(mapping->host, mapping, page_list,
					 &nr_pages);

	if (rc == 0)
		goto out;

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	if (fsc->mount_options->rsize >= PAGE_CACHE_SIZE)
		max = (fsc->mount_options->rsize + PAGE_CACHE_SIZE - 1)
			>> PAGE_SHIFT;
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	dout("readpages %p file %p nr_pages %d max %d\n", inode,
		file, nr_pages,
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	     max);
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	while (!list_empty(page_list)) {
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		rc = start_read(inode, page_list, max);
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		if (rc < 0)
			goto out;
		BUG_ON(rc == 0);
	}
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out:
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	ceph_fscache_readpages_cancel(inode, page_list);

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	dout("readpages %p file %p ret %d\n", inode, file, rc);
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	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.
 */
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static struct ceph_snap_context *get_oldest_context(struct inode *inode,
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						    loff_t *snap_size)
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{
	struct ceph_inode_info *ci = ceph_inode(inode);
	struct ceph_snap_context *snapc = NULL;
	struct ceph_cap_snap *capsnap = NULL;

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	spin_lock(&ci->i_ceph_lock);
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	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;
		}
	}
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	if (!snapc && ci->i_wrbuffer_ref_head) {
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		snapc = ceph_get_snap_context(ci->i_head_snapc);
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		dout(" head snapc %p has %d dirty pages\n",
		     snapc, ci->i_wrbuffer_ref_head);
	}
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	spin_unlock(&ci->i_ceph_lock);
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	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;
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	struct ceph_fs_client *fsc;
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	struct ceph_osd_client *osdc;
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	struct ceph_snap_context *snapc, *oldest;
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	loff_t page_off = page_offset(page);
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	loff_t snap_size = -1;
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	long writeback_stat;
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	u64 truncate_size;
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	u32 truncate_seq;
	int err = 0, len = PAGE_CACHE_SIZE;
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	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);
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	fsc = ceph_inode_to_client(inode);
	osdc = &fsc->client->osdc;
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	/* verify this is a writeable snap context */
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	snapc = page_snap_context(page);
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	if (snapc == NULL) {
		dout("writepage %p page %p not dirty?\n", inode, page);
		goto out;
	}
506 507
	oldest = get_oldest_context(inode, &snap_size);
	if (snapc->seq > oldest->seq) {
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		dout("writepage %p page %p snapc %p not writeable - noop\n",
509
		     inode, page, snapc);
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510 511
		/* we should only noop if called by kswapd */
		WARN_ON((current->flags & PF_MEMALLOC) == 0);
512
		ceph_put_snap_context(oldest);
S
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513 514
		goto out;
	}
515
	ceph_put_snap_context(oldest);
S
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516

517 518 519
	spin_lock(&ci->i_ceph_lock);
	truncate_seq = ci->i_truncate_seq;
	truncate_size = ci->i_truncate_size;
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	if (snap_size == -1)
521 522 523
		snap_size = i_size_read(inode);
	spin_unlock(&ci->i_ceph_lock);

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524
	/* is this a partial page at end of file? */
525 526 527 528 529 530
	if (page_off >= snap_size) {
		dout("%p page eof %llu\n", page, snap_size);
		goto out;
	}
	if (snap_size < page_off + len)
		len = snap_size - page_off;
S
Sage Weil 已提交
531

S
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532 533
	dout("writepage %p page %p index %lu on %llu~%u snapc %p\n",
	     inode, page, page->index, page_off, len, snapc);
S
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534

535
	writeback_stat = atomic_long_inc_return(&fsc->writeback_count);
Y
Yehuda Sadeh 已提交
536
	if (writeback_stat >
537 538
	    CONGESTION_ON_THRESH(fsc->mount_options->congestion_kb))
		set_bdi_congested(&fsc->backing_dev_info, BLK_RW_ASYNC);
Y
Yehuda Sadeh 已提交
539

540 541
	ceph_readpage_to_fscache(inode, page);

S
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542 543 544 545
	set_page_writeback(page);
	err = ceph_osdc_writepages(osdc, ceph_vino(inode),
				   &ci->i_layout, snapc,
				   page_off, len,
546
				   truncate_seq, truncate_size,
547
				   &inode->i_mtime, &page, 1);
S
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548 549 550 551 552 553 554 555 556 557 558 559 560 561
	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);
562
	ceph_put_snap_context(snapc);  /* page's reference */
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563 564 565 566 567 568
out:
	return err;
}

static int ceph_writepage(struct page *page, struct writeback_control *wbc)
{
569 570 571
	int err;
	struct inode *inode = page->mapping->host;
	BUG_ON(!inode);
572
	ihold(inode);
573
	err = writepage_nounlock(page, wbc);
S
Sage Weil 已提交
574
	unlock_page(page);
575
	iput(inode);
S
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576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607
	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_inode_info *ci = ceph_inode(inode);
608
	struct ceph_osd_data *osd_data;
S
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609
	struct page *page;
Y
Yan, Zheng 已提交
610 611 612
	int num_pages, total_pages = 0;
	int i, j;
	int rc = req->r_result;
S
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613 614
	struct ceph_snap_context *snapc = req->r_snapc;
	struct address_space *mapping = inode->i_mapping;
615
	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
Y
Yan, Zheng 已提交
616
	bool remove_page;
S
Sage Weil 已提交
617

Y
Yan, Zheng 已提交
618 619 620

	dout("writepages_finish %p rc %d\n", inode, rc);
	if (rc < 0)
S
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621
		mapping_set_error(mapping, rc);
Y
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622 623 624 625 626 627 628 629 630

	/*
	 * 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
	 */
	remove_page = !(ceph_caps_issued(ci) &
			(CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO));
S
Sage Weil 已提交
631 632

	/* clean all pages */
Y
Yan, Zheng 已提交
633 634 635
	for (i = 0; i < req->r_num_ops; i++) {
		if (req->r_ops[i].op != CEPH_OSD_OP_WRITE)
			break;
636

Y
Yan, Zheng 已提交
637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666
		osd_data = osd_req_op_extent_osd_data(req, i);
		BUG_ON(osd_data->type != CEPH_OSD_DATA_TYPE_PAGES);
		num_pages = calc_pages_for((u64)osd_data->alignment,
					   (u64)osd_data->length);
		total_pages += num_pages;
		for (j = 0; j < num_pages; j++) {
			page = osd_data->pages[j];
			BUG_ON(!page);
			WARN_ON(!PageUptodate(page));

			if (atomic_long_dec_return(&fsc->writeback_count) <
			     CONGESTION_OFF_THRESH(
					fsc->mount_options->congestion_kb))
				clear_bdi_congested(&fsc->backing_dev_info,
						    BLK_RW_ASYNC);

			ceph_put_snap_context(page_snap_context(page));
			page->private = 0;
			ClearPagePrivate(page);
			dout("unlocking %p\n", page);
			end_page_writeback(page);

			if (remove_page)
				generic_error_remove_page(inode->i_mapping,
							  page);

			unlock_page(page);
		}
		dout("writepages_finish %p wrote %llu bytes cleaned %d pages\n",
		     inode, osd_data->length, rc >= 0 ? num_pages : 0);
667

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Yan, Zheng 已提交
668
		ceph_release_pages(osd_data->pages, num_pages);
S
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669 670
	}

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671 672 673
	ceph_put_wrbuffer_cap_refs(ci, total_pages, snapc);

	osd_data = osd_req_op_extent_osd_data(req, 0);
674 675
	if (osd_data->pages_from_pool)
		mempool_free(osd_data->pages,
676
			     ceph_sb_to_client(inode->i_sb)->wb_pagevec_pool);
S
Sage Weil 已提交
677
	else
678
		kfree(osd_data->pages);
S
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679 680 681 682 683 684 685 686 687 688 689
	ceph_osdc_put_request(req);
}

/*
 * initiate async writeback
 */
static int ceph_writepages_start(struct address_space *mapping,
				 struct writeback_control *wbc)
{
	struct inode *inode = mapping->host;
	struct ceph_inode_info *ci = ceph_inode(inode);
690 691
	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
	struct ceph_vino vino = ceph_vino(inode);
S
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692 693 694 695
	pgoff_t index, start, end;
	int range_whole = 0;
	int should_loop = 1;
	pgoff_t max_pages = 0, max_pages_ever = 0;
696
	struct ceph_snap_context *snapc = NULL, *last_snapc = NULL, *pgsnapc;
S
Sage Weil 已提交
697 698 699 700 701
	struct pagevec pvec;
	int done = 0;
	int rc = 0;
	unsigned wsize = 1 << inode->i_blkbits;
	struct ceph_osd_request *req = NULL;
D
Dan Carpenter 已提交
702
	int do_sync = 0;
Y
Yan, Zheng 已提交
703 704
	loff_t snap_size, i_size;
	u64 truncate_size;
705
	u32 truncate_seq;
S
Sage Weil 已提交
706 707 708 709 710 711

	/*
	 * 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.
	 */
712 713
	if ((wbc->sync_mode == WB_SYNC_ALL) ||
		ceph_caps_revoking(ci, CEPH_CAP_FILE_BUFFER))
S
Sage Weil 已提交
714 715 716 717 718 719
		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"));

720
	if (ACCESS_ONCE(fsc->mount_state) == CEPH_MOUNT_SHUTDOWN) {
721
		pr_warn("writepage_start %p on forced umount\n", inode);
722 723
		truncate_pagecache(inode, 0);
		mapping_set_error(mapping, -EIO);
S
Sage Weil 已提交
724 725
		return -EIO; /* we're in a forced umount, don't write! */
	}
726 727
	if (fsc->mount_options->wsize && fsc->mount_options->wsize < wsize)
		wsize = fsc->mount_options->wsize;
S
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728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751
	if (wsize < PAGE_CACHE_SIZE)
		wsize = PAGE_CACHE_SIZE;
	max_pages_ever = wsize >> PAGE_CACHE_SHIFT;

	pagevec_init(&pvec, 0);

	/* 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);
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Yan, Zheng 已提交
752
	snap_size = -1;
S
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753 754 755 756 757 758 759 760 761
	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);
762 763 764 765

	spin_lock(&ci->i_ceph_lock);
	truncate_seq = ci->i_truncate_seq;
	truncate_size = ci->i_truncate_size;
Y
Yan, Zheng 已提交
766
	i_size = i_size_read(inode);
767 768
	spin_unlock(&ci->i_ceph_lock);

S
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769 770 771 772 773 774 775 776 777 778 779 780
	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;
Y
Yan, Zheng 已提交
781 782 783 784
		pgoff_t strip_unit_end = 0;
		int num_ops = 0, op_idx;
		int pvec_pages, locked_pages = 0;
		struct page **pages = NULL, **data_pages;
785
		mempool_t *pool = NULL;	/* Becomes non-null if mempool used */
S
Sage Weil 已提交
786 787
		struct page *page;
		int want;
Y
Yan, Zheng 已提交
788
		u64 offset = 0, len = 0;
S
Sage Weil 已提交
789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824

		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;
			}
Y
Yan, Zheng 已提交
825 826
			if (strip_unit_end && (page->index > strip_unit_end)) {
				dout("end of strip unit %p\n", page);
S
Sage Weil 已提交
827 828 829 830 831 832 833
				unlock_page(page);
				break;
			}
			if (wbc->sync_mode != WB_SYNC_NONE) {
				dout("waiting on writeback %p\n", page);
				wait_on_page_writeback(page);
			}
Y
Yan, Zheng 已提交
834 835 836 837
			if (page_offset(page) >=
			    (snap_size == -1 ? i_size : snap_size)) {
				dout("%p page eof %llu\n", page,
				     (snap_size == -1 ? i_size : snap_size));
S
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838 839 840 841 842 843 844 845 846 847 848
				done = 1;
				unlock_page(page);
				break;
			}
			if (PageWriteback(page)) {
				dout("%p under writeback\n", page);
				unlock_page(page);
				break;
			}

			/* only if matching snap context */
849
			pgsnapc = page_snap_context(page);
850 851 852
			if (pgsnapc->seq > snapc->seq) {
				dout("page snapc %p %lld > oldest %p %lld\n",
				     pgsnapc, pgsnapc->seq, snapc, snapc->seq);
S
Sage Weil 已提交
853 854 855 856 857 858 859 860 861 862 863 864
				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;
			}

865 866 867
			/*
			 * We have something to write.  If this is
			 * the first locked page this time through,
Y
Yan, Zheng 已提交
868 869
			 * calculate max possinle write size and
			 * allocate a page array
870
			 */
S
Sage Weil 已提交
871
			if (locked_pages == 0) {
Y
Yan, Zheng 已提交
872 873 874
				u64 objnum;
				u64 objoff;

S
Sage Weil 已提交
875
				/* prepare async write request */
876
				offset = (u64)page_offset(page);
S
Sage Weil 已提交
877
				len = wsize;
Y
Yan, Zheng 已提交
878 879 880 881 882 883

				rc = ceph_calc_file_object_mapping(&ci->i_layout,
								offset, len,
								&objnum, &objoff,
								&len);
				if (rc < 0) {
884 885 886 887
					unlock_page(page);
					break;
				}

Y
Yan, Zheng 已提交
888 889 890
				num_ops = 1 + do_sync;
				strip_unit_end = page->index +
					((len - 1) >> PAGE_CACHE_SHIFT);
A
Alex Elder 已提交
891

Y
Yan, Zheng 已提交
892
				BUG_ON(pages);
A
Alex Elder 已提交
893
				max_pages = calc_pages_for(0, (u64)len);
894 895
				pages = kmalloc(max_pages * sizeof (*pages),
						GFP_NOFS);
A
Alex Elder 已提交
896 897 898
				if (!pages) {
					pool = fsc->wb_pagevec_pool;
					pages = mempool_alloc(pool, GFP_NOFS);
899
					BUG_ON(!pages);
A
Alex Elder 已提交
900
				}
Y
Yan, Zheng 已提交
901 902 903 904 905 906 907 908 909 910 911 912 913 914

				len = 0;
			} else if (page->index !=
				   (offset + len) >> PAGE_CACHE_SHIFT) {
				if (num_ops >= (pool ?  CEPH_OSD_SLAB_OPS :
							CEPH_OSD_MAX_OPS)) {
					redirty_page_for_writepage(wbc, page);
					unlock_page(page);
					break;
				}

				num_ops++;
				offset = (u64)page_offset(page);
				len = 0;
S
Sage Weil 已提交
915 916 917 918 919 920 921
			}

			/* 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);
Y
Yehuda Sadeh 已提交
922

Y
Yan, Zheng 已提交
923 924
			if (atomic_long_inc_return(&fsc->writeback_count) >
			    CONGESTION_ON_THRESH(
925 926
				    fsc->mount_options->congestion_kb)) {
				set_bdi_congested(&fsc->backing_dev_info,
S
Sage Weil 已提交
927
						  BLK_RW_ASYNC);
Y
Yehuda Sadeh 已提交
928 929
			}

930
			pages[locked_pages] = page;
S
Sage Weil 已提交
931
			locked_pages++;
Y
Yan, Zheng 已提交
932
			len += PAGE_CACHE_SIZE;
S
Sage Weil 已提交
933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951
		}

		/* 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++) {
Y
Yan, Zheng 已提交
952
				dout(" pvec leftover page %p\n", pvec.pages[j]);
S
Sage Weil 已提交
953 954 955 956 957
				pvec.pages[j-i+first] = pvec.pages[j];
			}
			pvec.nr -= i-first;
		}

Y
Yan, Zheng 已提交
958
new_request:
959
		offset = page_offset(pages[0]);
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Yan, Zheng 已提交
960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981
		len = wsize;

		req = ceph_osdc_new_request(&fsc->client->osdc,
					&ci->i_layout, vino,
					offset, &len, 0, num_ops,
					CEPH_OSD_OP_WRITE,
					CEPH_OSD_FLAG_WRITE |
					CEPH_OSD_FLAG_ONDISK,
					snapc, truncate_seq,
					truncate_size, false);
		if (IS_ERR(req)) {
			req = ceph_osdc_new_request(&fsc->client->osdc,
						&ci->i_layout, vino,
						offset, &len, 0,
						min(num_ops,
						    CEPH_OSD_SLAB_OPS),
						CEPH_OSD_OP_WRITE,
						CEPH_OSD_FLAG_WRITE |
						CEPH_OSD_FLAG_ONDISK,
						snapc, truncate_seq,
						truncate_size, true);
			BUG_ON(IS_ERR(req));
Y
Yan, Zheng 已提交
982
		}
Y
Yan, Zheng 已提交
983 984 985 986 987
		BUG_ON(len < page_offset(pages[locked_pages - 1]) +
			     PAGE_CACHE_SIZE - offset);

		req->r_callback = writepages_finish;
		req->r_inode = inode;
S
Sage Weil 已提交
988

Y
Yan, Zheng 已提交
989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003
		/* Format the osd request message and submit the write */
		len = 0;
		data_pages = pages;
		op_idx = 0;
		for (i = 0; i < locked_pages; i++) {
			u64 cur_offset = page_offset(pages[i]);
			if (offset + len != cur_offset) {
				if (op_idx + do_sync + 1 == req->r_num_ops)
					break;
				osd_req_op_extent_dup_last(req, op_idx,
							   cur_offset - offset);
				dout("writepages got pages at %llu~%llu\n",
				     offset, len);
				osd_req_op_extent_osd_data_pages(req, op_idx,
							data_pages, len, 0,
1004
							!!pool, false);
Y
Yan, Zheng 已提交
1005
				osd_req_op_extent_update(req, op_idx, len);
1006

Y
Yan, Zheng 已提交
1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027
				len = 0;
				offset = cur_offset; 
				data_pages = pages + i;
				op_idx++;
			}

			set_page_writeback(pages[i]);
			len += PAGE_CACHE_SIZE;
		}

		if (snap_size != -1) {
			len = min(len, snap_size - offset);
		} else if (i == locked_pages) {
			/* writepages_finish() clears writeback pages
			 * according to the data length, so make sure
			 * data length covers all locked pages */
			u64 min_len = len + 1 - PAGE_CACHE_SIZE;
			len = min(len, (u64)i_size_read(inode) - offset);
			len = max(len, min_len);
		}
		dout("writepages got pages at %llu~%llu\n", offset, len);
1028

Y
Yan, Zheng 已提交
1029 1030 1031
		osd_req_op_extent_osd_data_pages(req, op_idx, data_pages, len,
						 0, !!pool, false);
		osd_req_op_extent_update(req, op_idx, len);
1032

Y
Yan, Zheng 已提交
1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064
		if (do_sync) {
			op_idx++;
			osd_req_op_init(req, op_idx, CEPH_OSD_OP_STARTSYNC, 0);
		}
		BUG_ON(op_idx + 1 != req->r_num_ops);

		pool = NULL;
		if (i < locked_pages) {
			BUG_ON(num_ops <= req->r_num_ops);
			num_ops -= req->r_num_ops;
			num_ops += do_sync;
			locked_pages -= i;

			/* allocate new pages array for next request */
			data_pages = pages;
			pages = kmalloc(locked_pages * sizeof (*pages),
					GFP_NOFS);
			if (!pages) {
				pool = fsc->wb_pagevec_pool;
				pages = mempool_alloc(pool, GFP_NOFS);
				BUG_ON(!pages);
			}
			memcpy(pages, data_pages + i,
			       locked_pages * sizeof(*pages));
			memset(data_pages + i, 0,
			       locked_pages * sizeof(*pages));
		} else {
			BUG_ON(num_ops != req->r_num_ops);
			index = pages[i - 1]->index + 1;
			/* request message now owns the pages array */
			pages = NULL;
		}
1065 1066

		vino = ceph_vino(inode);
1067 1068
		ceph_osdc_build_request(req, offset, snapc, vino.snap,
					&inode->i_mtime);
S
Sage Weil 已提交
1069

1070 1071
		rc = ceph_osdc_start_request(&fsc->client->osdc, req, true);
		BUG_ON(rc);
S
Sage Weil 已提交
1072 1073
		req = NULL;

Y
Yan, Zheng 已提交
1074 1075 1076 1077
		wbc->nr_to_write -= i;
		if (pages)
			goto new_request;

S
Sage Weil 已提交
1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117
		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);
	ceph_put_snap_context(snapc);
	dout("writepages done, rc = %d\n", rc);
	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);
1118 1119 1120 1121
	int ret = !oldest || snapc->seq <= oldest->seq;

	ceph_put_snap_context(oldest);
	return ret;
S
Sage Weil 已提交
1122 1123 1124 1125 1126
}

/*
 * We are only allowed to write into/dirty the page if the page is
 * clean, or already dirty within the same snap context.
1127 1128 1129 1130
 *
 * called with page locked.
 * return success with page locked,
 * or any failure (incl -EAGAIN) with page unlocked.
S
Sage Weil 已提交
1131
 */
1132 1133 1134
static int ceph_update_writeable_page(struct file *file,
			    loff_t pos, unsigned len,
			    struct page *page)
S
Sage Weil 已提交
1135
{
A
Al Viro 已提交
1136
	struct inode *inode = file_inode(file);
S
Sage Weil 已提交
1137 1138 1139 1140 1141 1142
	struct ceph_inode_info *ci = ceph_inode(inode);
	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;
	int r;
1143
	struct ceph_snap_context *snapc, *oldest;
S
Sage Weil 已提交
1144 1145 1146 1147 1148

retry_locked:
	/* writepages currently holds page lock, but if we change that later, */
	wait_on_page_writeback(page);

1149
	snapc = page_snap_context(page);
1150
	if (snapc && snapc != ci->i_head_snapc) {
S
Sage Weil 已提交
1151 1152 1153 1154
		/*
		 * this page is already dirty in another (older) snap
		 * context!  is it writeable now?
		 */
1155
		oldest = get_oldest_context(inode, NULL);
S
Sage Weil 已提交
1156

1157
		if (snapc->seq > oldest->seq) {
1158
			ceph_put_snap_context(oldest);
S
Sage Weil 已提交
1159
			dout(" page %p snapc %p not current or oldest\n",
1160
			     page, snapc);
S
Sage Weil 已提交
1161 1162 1163 1164
			/*
			 * queue for writeback, and wait for snapc to
			 * be writeable or written
			 */
1165
			snapc = ceph_get_snap_context(snapc);
S
Sage Weil 已提交
1166
			unlock_page(page);
1167
			ceph_queue_writeback(inode);
1168
			r = wait_event_interruptible(ci->i_cap_wq,
S
Sage Weil 已提交
1169 1170
			       context_is_writeable_or_written(inode, snapc));
			ceph_put_snap_context(snapc);
1171 1172
			if (r == -ERESTARTSYS)
				return r;
1173
			return -EAGAIN;
S
Sage Weil 已提交
1174
		}
1175
		ceph_put_snap_context(oldest);
S
Sage Weil 已提交
1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197

		/* 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? */
1198
	i_size = i_size_read(inode);
S
Sage Weil 已提交
1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220

	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. */
	r = readpage_nounlock(file, page);
	if (r < 0)
		goto fail_nosnap;
	goto retry_locked;
fail_nosnap:
	unlock_page(page);
	return r;
}

1221 1222 1223 1224 1225 1226 1227 1228
/*
 * 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)
{
A
Al Viro 已提交
1229
	struct inode *inode = file_inode(file);
1230 1231
	struct page *page;
	pgoff_t index = pos >> PAGE_CACHE_SHIFT;
S
Sage Weil 已提交
1232
	int r;
1233 1234

	do {
1235
		/* get a page */
1236
		page = grab_cache_page_write_begin(mapping, index, 0);
S
Sage Weil 已提交
1237 1238
		if (!page)
			return -ENOMEM;
1239 1240

		dout("write_begin file %p inode %p page %p %d~%d\n", file,
S
Sage Weil 已提交
1241
		     inode, page, (int)pos, (int)len);
1242 1243

		r = ceph_update_writeable_page(file, pos, len, page);
1244 1245 1246 1247
		if (r < 0)
			page_cache_release(page);
		else
			*pagep = page;
1248 1249 1250 1251 1252
	} while (r == -EAGAIN);

	return r;
}

S
Sage Weil 已提交
1253 1254
/*
 * we don't do anything in here that simple_write_end doesn't do
1255
 * except adjust dirty page accounting
S
Sage Weil 已提交
1256 1257 1258 1259 1260
 */
static int ceph_write_end(struct file *file, struct address_space *mapping,
			  loff_t pos, unsigned len, unsigned copied,
			  struct page *page, void *fsdata)
{
A
Al Viro 已提交
1261
	struct inode *inode = file_inode(file);
S
Sage Weil 已提交
1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272
	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? */
1273
	if (pos+copied > i_size_read(inode))
S
Sage Weil 已提交
1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294
		check_cap = ceph_inode_set_size(inode, pos+copied);

	if (!PageUptodate(page))
		SetPageUptodate(page);

	set_page_dirty(page);

	unlock_page(page);
	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.
 */
1295
static ssize_t ceph_direct_io(struct kiocb *iocb, struct iov_iter *iter,
A
Al Viro 已提交
1296
			      loff_t pos)
S
Sage Weil 已提交
1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318
{
	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
 */
1319 1320 1321 1322 1323
static int ceph_filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
{
	struct inode *inode = file_inode(vma->vm_file);
	struct ceph_inode_info *ci = ceph_inode(inode);
	struct ceph_file_info *fi = vma->vm_file->private_data;
1324
	struct page *pinned_page = NULL;
1325 1326 1327 1328
	loff_t off = vmf->pgoff << PAGE_CACHE_SHIFT;
	int want, got, ret;

	dout("filemap_fault %p %llx.%llx %llu~%zd trying to get caps\n",
1329
	     inode, ceph_vinop(inode), off, (size_t)PAGE_CACHE_SIZE);
1330 1331 1332 1333 1334 1335
	if (fi->fmode & CEPH_FILE_MODE_LAZY)
		want = CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO;
	else
		want = CEPH_CAP_FILE_CACHE;
	while (1) {
		got = 0;
Y
Yan, Zheng 已提交
1336 1337
		ret = ceph_get_caps(ci, CEPH_CAP_FILE_RD, want,
				    -1, &got, &pinned_page);
1338 1339 1340 1341 1342 1343 1344 1345
		if (ret == 0)
			break;
		if (ret != -ERESTARTSYS) {
			WARN_ON(1);
			return VM_FAULT_SIGBUS;
		}
	}
	dout("filemap_fault %p %llu~%zd got cap refs on %s\n",
1346
	     inode, off, (size_t)PAGE_CACHE_SIZE, ceph_cap_string(got));
1347

Y
Yan, Zheng 已提交
1348 1349 1350 1351 1352
	if ((got & (CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO)) ||
	    ci->i_inline_version == CEPH_INLINE_NONE)
		ret = filemap_fault(vma, vmf);
	else
		ret = -EAGAIN;
1353 1354

	dout("filemap_fault %p %llu~%zd dropping cap refs on %s ret %d\n",
1355
	     inode, off, (size_t)PAGE_CACHE_SIZE, ceph_cap_string(got), ret);
1356 1357
	if (pinned_page)
		page_cache_release(pinned_page);
1358 1359
	ceph_put_cap_refs(ci, got);

Y
Yan, Zheng 已提交
1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370
	if (ret != -EAGAIN)
		return ret;

	/* read inline data */
	if (off >= PAGE_CACHE_SIZE) {
		/* does not support inline data > PAGE_SIZE */
		ret = VM_FAULT_SIGBUS;
	} else {
		int ret1;
		struct address_space *mapping = inode->i_mapping;
		struct page *page = find_or_create_page(mapping, 0,
1371 1372
						mapping_gfp_constraint(mapping,
						~__GFP_FS));
Y
Yan, Zheng 已提交
1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395
		if (!page) {
			ret = VM_FAULT_OOM;
			goto out;
		}
		ret1 = __ceph_do_getattr(inode, page,
					 CEPH_STAT_CAP_INLINE_DATA, true);
		if (ret1 < 0 || off >= i_size_read(inode)) {
			unlock_page(page);
			page_cache_release(page);
			ret = VM_FAULT_SIGBUS;
			goto out;
		}
		if (ret1 < PAGE_CACHE_SIZE)
			zero_user_segment(page, ret1, PAGE_CACHE_SIZE);
		else
			flush_dcache_page(page);
		SetPageUptodate(page);
		vmf->page = page;
		ret = VM_FAULT_MAJOR | VM_FAULT_LOCKED;
	}
out:
	dout("filemap_fault %p %llu~%zd read inline data ret %d\n",
	     inode, off, (size_t)PAGE_CACHE_SIZE, ret);
1396 1397
	return ret;
}
S
Sage Weil 已提交
1398 1399 1400 1401 1402 1403

/*
 * Reuse write_begin here for simplicity.
 */
static int ceph_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
{
A
Al Viro 已提交
1404
	struct inode *inode = file_inode(vma->vm_file);
1405 1406
	struct ceph_inode_info *ci = ceph_inode(inode);
	struct ceph_file_info *fi = vma->vm_file->private_data;
1407
	struct ceph_cap_flush *prealloc_cf;
1408
	struct page *page = vmf->page;
1409
	loff_t off = page_offset(page);
1410 1411 1412
	loff_t size = i_size_read(inode);
	size_t len;
	int want, got, ret;
1413

1414 1415 1416 1417
	prealloc_cf = ceph_alloc_cap_flush();
	if (!prealloc_cf)
		return VM_FAULT_SIGBUS;

1418 1419 1420 1421 1422 1423 1424 1425 1426
	if (ci->i_inline_version != CEPH_INLINE_NONE) {
		struct page *locked_page = NULL;
		if (off == 0) {
			lock_page(page);
			locked_page = page;
		}
		ret = ceph_uninline_data(vma->vm_file, locked_page);
		if (locked_page)
			unlock_page(locked_page);
1427 1428 1429 1430
		if (ret < 0) {
			ret = VM_FAULT_SIGBUS;
			goto out_free;
		}
1431 1432
	}

S
Sage Weil 已提交
1433 1434 1435 1436 1437
	if (off + PAGE_CACHE_SIZE <= size)
		len = PAGE_CACHE_SIZE;
	else
		len = size & ~PAGE_CACHE_MASK;

1438 1439 1440 1441 1442 1443 1444 1445
	dout("page_mkwrite %p %llx.%llx %llu~%zd getting caps i_size %llu\n",
	     inode, ceph_vinop(inode), off, len, size);
	if (fi->fmode & CEPH_FILE_MODE_LAZY)
		want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO;
	else
		want = CEPH_CAP_FILE_BUFFER;
	while (1) {
		got = 0;
1446 1447
		ret = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, off + len,
				    &got, NULL);
1448 1449 1450 1451
		if (ret == 0)
			break;
		if (ret != -ERESTARTSYS) {
			WARN_ON(1);
1452 1453
			ret = VM_FAULT_SIGBUS;
			goto out_free;
1454 1455 1456 1457 1458 1459 1460
		}
	}
	dout("page_mkwrite %p %llu~%zd got cap refs on %s\n",
	     inode, off, len, ceph_cap_string(got));

	/* Update time before taking page lock */
	file_update_time(vma->vm_file);
1461 1462 1463 1464 1465

	lock_page(page);

	ret = VM_FAULT_NOPAGE;
	if ((off > size) ||
1466 1467
	    (page->mapping != inode->i_mapping)) {
		unlock_page(page);
1468
		goto out;
1469
	}
1470 1471

	ret = ceph_update_writeable_page(vma->vm_file, off, len, page);
1472
	if (ret >= 0) {
1473
		/* success.  we'll keep the page locked. */
S
Sage Weil 已提交
1474 1475 1476
		set_page_dirty(page);
		ret = VM_FAULT_LOCKED;
	} else {
1477 1478 1479 1480
		if (ret == -ENOMEM)
			ret = VM_FAULT_OOM;
		else
			ret = VM_FAULT_SIGBUS;
S
Sage Weil 已提交
1481
	}
1482
out:
1483 1484
	if (ret == VM_FAULT_LOCKED ||
	    ci->i_inline_version != CEPH_INLINE_NONE) {
1485 1486
		int dirty;
		spin_lock(&ci->i_ceph_lock);
1487
		ci->i_inline_version = CEPH_INLINE_NONE;
1488 1489
		dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR,
					       &prealloc_cf);
1490 1491 1492 1493 1494 1495 1496 1497
		spin_unlock(&ci->i_ceph_lock);
		if (dirty)
			__mark_inode_dirty(inode, dirty);
	}

	dout("page_mkwrite %p %llu~%zd dropping cap refs on %s ret %d\n",
	     inode, off, len, ceph_cap_string(got), ret);
	ceph_put_cap_refs(ci, got);
1498 1499
out_free:
	ceph_free_cap_flush(prealloc_cf);
1500

S
Sage Weil 已提交
1501 1502 1503
	return ret;
}

Y
Yan, Zheng 已提交
1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515
void ceph_fill_inline_data(struct inode *inode, struct page *locked_page,
			   char	*data, size_t len)
{
	struct address_space *mapping = inode->i_mapping;
	struct page *page;

	if (locked_page) {
		page = locked_page;
	} else {
		if (i_size_read(inode) == 0)
			return;
		page = find_or_create_page(mapping, 0,
1516 1517
					   mapping_gfp_constraint(mapping,
					   ~__GFP_FS));
Y
Yan, Zheng 已提交
1518 1519 1520 1521 1522 1523 1524 1525 1526
		if (!page)
			return;
		if (PageUptodate(page)) {
			unlock_page(page);
			page_cache_release(page);
			return;
		}
	}

1527
	dout("fill_inline_data %p %llx.%llx len %zu locked_page %p\n",
Y
Yan, Zheng 已提交
1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547
	     inode, ceph_vinop(inode), len, locked_page);

	if (len > 0) {
		void *kaddr = kmap_atomic(page);
		memcpy(kaddr, data, len);
		kunmap_atomic(kaddr);
	}

	if (page != locked_page) {
		if (len < PAGE_CACHE_SIZE)
			zero_user_segment(page, len, PAGE_CACHE_SIZE);
		else
			flush_dcache_page(page);

		SetPageUptodate(page);
		unlock_page(page);
		page_cache_release(page);
	}
}

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int ceph_uninline_data(struct file *filp, struct page *locked_page)
{
	struct inode *inode = file_inode(filp);
	struct ceph_inode_info *ci = ceph_inode(inode);
	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
	struct ceph_osd_request *req;
	struct page *page = NULL;
	u64 len, inline_version;
	int err = 0;
	bool from_pagecache = false;

	spin_lock(&ci->i_ceph_lock);
	inline_version = ci->i_inline_version;
	spin_unlock(&ci->i_ceph_lock);

	dout("uninline_data %p %llx.%llx inline_version %llu\n",
	     inode, ceph_vinop(inode), inline_version);

	if (inline_version == 1 || /* initial version, no data */
	    inline_version == CEPH_INLINE_NONE)
		goto out;

	if (locked_page) {
		page = locked_page;
		WARN_ON(!PageUptodate(page));
	} else if (ceph_caps_issued(ci) &
		   (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) {
		page = find_get_page(inode->i_mapping, 0);
		if (page) {
			if (PageUptodate(page)) {
				from_pagecache = true;
				lock_page(page);
			} else {
				page_cache_release(page);
				page = NULL;
			}
		}
	}

	if (page) {
		len = i_size_read(inode);
		if (len > PAGE_CACHE_SIZE)
			len = PAGE_CACHE_SIZE;
	} else {
		page = __page_cache_alloc(GFP_NOFS);
		if (!page) {
			err = -ENOMEM;
			goto out;
		}
		err = __ceph_do_getattr(inode, page,
					CEPH_STAT_CAP_INLINE_DATA, true);
		if (err < 0) {
			/* no inline data */
			if (err == -ENODATA)
				err = 0;
			goto out;
		}
		len = err;
	}

	req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
				    ceph_vino(inode), 0, &len, 0, 1,
				    CEPH_OSD_OP_CREATE,
				    CEPH_OSD_FLAG_ONDISK | CEPH_OSD_FLAG_WRITE,
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				    NULL, 0, 0, false);
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	if (IS_ERR(req)) {
		err = PTR_ERR(req);
		goto out;
	}

	ceph_osdc_build_request(req, 0, NULL, CEPH_NOSNAP, &inode->i_mtime);
	err = ceph_osdc_start_request(&fsc->client->osdc, req, false);
	if (!err)
		err = ceph_osdc_wait_request(&fsc->client->osdc, req);
	ceph_osdc_put_request(req);
	if (err < 0)
		goto out;

	req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
				    ceph_vino(inode), 0, &len, 1, 3,
				    CEPH_OSD_OP_WRITE,
				    CEPH_OSD_FLAG_ONDISK | CEPH_OSD_FLAG_WRITE,
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				    NULL, ci->i_truncate_seq,
				    ci->i_truncate_size, false);
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	if (IS_ERR(req)) {
		err = PTR_ERR(req);
		goto out;
	}

	osd_req_op_extent_osd_data_pages(req, 1, &page, len, 0, false, false);

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Yan, Zheng 已提交
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	{
		__le64 xattr_buf = cpu_to_le64(inline_version);
		err = osd_req_op_xattr_init(req, 0, CEPH_OSD_OP_CMPXATTR,
					    "inline_version", &xattr_buf,
					    sizeof(xattr_buf),
					    CEPH_OSD_CMPXATTR_OP_GT,
					    CEPH_OSD_CMPXATTR_MODE_U64);
		if (err)
			goto out_put;
	}

	{
		char xattr_buf[32];
		int xattr_len = snprintf(xattr_buf, sizeof(xattr_buf),
					 "%llu", inline_version);
		err = osd_req_op_xattr_init(req, 2, CEPH_OSD_OP_SETXATTR,
					    "inline_version",
					    xattr_buf, xattr_len, 0, 0);
		if (err)
			goto out_put;
	}
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	ceph_osdc_build_request(req, 0, NULL, CEPH_NOSNAP, &inode->i_mtime);
	err = ceph_osdc_start_request(&fsc->client->osdc, req, false);
	if (!err)
		err = ceph_osdc_wait_request(&fsc->client->osdc, req);
out_put:
	ceph_osdc_put_request(req);
	if (err == -ECANCELED)
		err = 0;
out:
	if (page && page != locked_page) {
		if (from_pagecache) {
			unlock_page(page);
			page_cache_release(page);
		} else
			__free_pages(page, 0);
	}

	dout("uninline_data %p %llx.%llx inline_version %llu = %d\n",
	     inode, ceph_vinop(inode), inline_version, err);
	return err;
}

1683
static const struct vm_operations_struct ceph_vmops = {
1684
	.fault		= ceph_filemap_fault,
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Sage Weil 已提交
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	.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;
	return 0;
}
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enum {
	POOL_READ	= 1,
	POOL_WRITE	= 2,
};

static int __ceph_pool_perm_get(struct ceph_inode_info *ci, u32 pool)
{
	struct ceph_fs_client *fsc = ceph_inode_to_client(&ci->vfs_inode);
	struct ceph_mds_client *mdsc = fsc->mdsc;
	struct ceph_osd_request *rd_req = NULL, *wr_req = NULL;
	struct rb_node **p, *parent;
	struct ceph_pool_perm *perm;
	struct page **pages;
	int err = 0, err2 = 0, have = 0;

	down_read(&mdsc->pool_perm_rwsem);
	p = &mdsc->pool_perm_tree.rb_node;
	while (*p) {
		perm = rb_entry(*p, struct ceph_pool_perm, node);
		if (pool < perm->pool)
			p = &(*p)->rb_left;
		else if (pool > perm->pool)
			p = &(*p)->rb_right;
		else {
			have = perm->perm;
			break;
		}
	}
	up_read(&mdsc->pool_perm_rwsem);
	if (*p)
		goto out;

	dout("__ceph_pool_perm_get pool %u no perm cached\n", pool);

	down_write(&mdsc->pool_perm_rwsem);
	parent = NULL;
	while (*p) {
		parent = *p;
		perm = rb_entry(parent, struct ceph_pool_perm, node);
		if (pool < perm->pool)
			p = &(*p)->rb_left;
		else if (pool > perm->pool)
			p = &(*p)->rb_right;
		else {
			have = perm->perm;
			break;
		}
	}
	if (*p) {
		up_write(&mdsc->pool_perm_rwsem);
		goto out;
	}

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	rd_req = ceph_osdc_alloc_request(&fsc->client->osdc, NULL,
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					 1, false, GFP_NOFS);
	if (!rd_req) {
		err = -ENOMEM;
		goto out_unlock;
	}

	rd_req->r_flags = CEPH_OSD_FLAG_READ;
	osd_req_op_init(rd_req, 0, CEPH_OSD_OP_STAT, 0);
	rd_req->r_base_oloc.pool = pool;
	snprintf(rd_req->r_base_oid.name, sizeof(rd_req->r_base_oid.name),
		 "%llx.00000000", ci->i_vino.ino);
	rd_req->r_base_oid.name_len = strlen(rd_req->r_base_oid.name);

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Ilya Dryomov 已提交
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	wr_req = ceph_osdc_alloc_request(&fsc->client->osdc, NULL,
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					 1, false, GFP_NOFS);
	if (!wr_req) {
		err = -ENOMEM;
		goto out_unlock;
	}

	wr_req->r_flags = CEPH_OSD_FLAG_WRITE |
			  CEPH_OSD_FLAG_ACK | CEPH_OSD_FLAG_ONDISK;
	osd_req_op_init(wr_req, 0, CEPH_OSD_OP_CREATE, CEPH_OSD_OP_FLAG_EXCL);
	wr_req->r_base_oloc.pool = pool;
	wr_req->r_base_oid = rd_req->r_base_oid;

	/* one page should be large enough for STAT data */
	pages = ceph_alloc_page_vector(1, GFP_KERNEL);
	if (IS_ERR(pages)) {
		err = PTR_ERR(pages);
		goto out_unlock;
	}

	osd_req_op_raw_data_in_pages(rd_req, 0, pages, PAGE_SIZE,
				     0, false, true);
	ceph_osdc_build_request(rd_req, 0, NULL, CEPH_NOSNAP,
				&ci->vfs_inode.i_mtime);
	err = ceph_osdc_start_request(&fsc->client->osdc, rd_req, false);

	ceph_osdc_build_request(wr_req, 0, NULL, CEPH_NOSNAP,
				&ci->vfs_inode.i_mtime);
	err2 = ceph_osdc_start_request(&fsc->client->osdc, wr_req, false);

	if (!err)
		err = ceph_osdc_wait_request(&fsc->client->osdc, rd_req);
	if (!err2)
		err2 = ceph_osdc_wait_request(&fsc->client->osdc, wr_req);

	if (err >= 0 || err == -ENOENT)
		have |= POOL_READ;
	else if (err != -EPERM)
		goto out_unlock;

	if (err2 == 0 || err2 == -EEXIST)
		have |= POOL_WRITE;
	else if (err2 != -EPERM) {
		err = err2;
		goto out_unlock;
	}

	perm = kmalloc(sizeof(*perm), GFP_NOFS);
	if (!perm) {
		err = -ENOMEM;
		goto out_unlock;
	}

	perm->pool = pool;
	perm->perm = have;
	rb_link_node(&perm->node, parent, p);
	rb_insert_color(&perm->node, &mdsc->pool_perm_tree);
	err = 0;
out_unlock:
	up_write(&mdsc->pool_perm_rwsem);

	if (rd_req)
		ceph_osdc_put_request(rd_req);
	if (wr_req)
		ceph_osdc_put_request(wr_req);
out:
	if (!err)
		err = have;
	dout("__ceph_pool_perm_get pool %u result = %d\n", pool, err);
	return err;
}

int ceph_pool_perm_check(struct ceph_inode_info *ci, int need)
{
	u32 pool;
	int ret, flags;

1843 1844 1845 1846
	/* does not support pool namespace yet */
	if (ci->i_pool_ns_len)
		return -EIO;

1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902
	if (ceph_test_mount_opt(ceph_inode_to_client(&ci->vfs_inode),
				NOPOOLPERM))
		return 0;

	spin_lock(&ci->i_ceph_lock);
	flags = ci->i_ceph_flags;
	pool = ceph_file_layout_pg_pool(ci->i_layout);
	spin_unlock(&ci->i_ceph_lock);
check:
	if (flags & CEPH_I_POOL_PERM) {
		if ((need & CEPH_CAP_FILE_RD) && !(flags & CEPH_I_POOL_RD)) {
			dout("ceph_pool_perm_check pool %u no read perm\n",
			     pool);
			return -EPERM;
		}
		if ((need & CEPH_CAP_FILE_WR) && !(flags & CEPH_I_POOL_WR)) {
			dout("ceph_pool_perm_check pool %u no write perm\n",
			     pool);
			return -EPERM;
		}
		return 0;
	}

	ret = __ceph_pool_perm_get(ci, pool);
	if (ret < 0)
		return ret;

	flags = CEPH_I_POOL_PERM;
	if (ret & POOL_READ)
		flags |= CEPH_I_POOL_RD;
	if (ret & POOL_WRITE)
		flags |= CEPH_I_POOL_WR;

	spin_lock(&ci->i_ceph_lock);
	if (pool == ceph_file_layout_pg_pool(ci->i_layout)) {
		ci->i_ceph_flags = flags;
        } else {
		pool = ceph_file_layout_pg_pool(ci->i_layout);
		flags = ci->i_ceph_flags;
	}
	spin_unlock(&ci->i_ceph_lock);
	goto check;
}

void ceph_pool_perm_destroy(struct ceph_mds_client *mdsc)
{
	struct ceph_pool_perm *perm;
	struct rb_node *n;

	while (!RB_EMPTY_ROOT(&mdsc->pool_perm_tree)) {
		n = rb_first(&mdsc->pool_perm_tree);
		perm = rb_entry(n, struct ceph_pool_perm, node);
		rb_erase(n, &mdsc->pool_perm_tree);
		kfree(perm);
	}
}