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-rw-r--r--kernel/fs/ceph/addr.c1599
1 files changed, 1599 insertions, 0 deletions
diff --git a/kernel/fs/ceph/addr.c b/kernel/fs/ceph/addr.c
new file mode 100644
index 000000000..e162bcd10
--- /dev/null
+++ b/kernel/fs/ceph/addr.c
@@ -0,0 +1,1599 @@
+#include <linux/ceph/ceph_debug.h>
+
+#include <linux/backing-dev.h>
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/pagemap.h>
+#include <linux/writeback.h> /* generic_writepages */
+#include <linux/slab.h>
+#include <linux/pagevec.h>
+#include <linux/task_io_accounting_ops.h>
+
+#include "super.h"
+#include "mds_client.h"
+#include "cache.h"
+#include <linux/ceph/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 absence 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.
+ */
+
+#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))
+
+static inline struct ceph_snap_context *page_snap_context(struct page *page)
+{
+ if (PagePrivate(page))
+ return (void *)page->private;
+ return NULL;
+}
+
+/*
+ * 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;
+ int ret;
+
+ if (unlikely(!mapping))
+ return !TestSetPageDirty(page);
+
+ if (PageDirty(page)) {
+ dout("%p set_page_dirty %p idx %lu -- already dirty\n",
+ mapping->host, page, page->index);
+ BUG_ON(!PagePrivate(page));
+ 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(&ci->i_ceph_lock);
+ if (ci->i_head_snapc == NULL)
+ ci->i_head_snapc = ceph_get_snap_context(snapc);
+ ++ci->i_wrbuffer_ref_head;
+ if (ci->i_wrbuffer_ref == 0)
+ ihold(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(&ci->i_ceph_lock);
+
+ /*
+ * 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);
+
+ ret = __set_page_dirty_nobuffers(page);
+ WARN_ON(!PageLocked(page));
+ WARN_ON(!page->mapping);
+
+ return ret;
+}
+
+/*
+ * 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 int offset,
+ unsigned int length)
+{
+ struct inode *inode;
+ struct ceph_inode_info *ci;
+ struct ceph_snap_context *snapc = page_snap_context(page);
+
+ inode = page->mapping->host;
+ 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;
+ }
+
+ ceph_invalidate_fscache_page(inode, page);
+
+ if (!PagePrivate(page))
+ return;
+
+ /*
+ * 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);
+
+ ClearPageChecked(page);
+
+ 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);
+}
+
+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));
+
+ /* Can we release the page from the cache? */
+ if (!ceph_release_fscache_page(page, g))
+ return 0;
+
+ return !PagePrivate(page);
+}
+
+/*
+ * read a single page, without unlocking it.
+ */
+static int readpage_nounlock(struct file *filp, struct page *page)
+{
+ struct inode *inode = file_inode(filp);
+ struct ceph_inode_info *ci = ceph_inode(inode);
+ struct ceph_osd_client *osdc =
+ &ceph_inode_to_client(inode)->client->osdc;
+ int err = 0;
+ u64 off = page_offset(page);
+ u64 len = PAGE_CACHE_SIZE;
+
+ if (off >= i_size_read(inode)) {
+ zero_user_segment(page, 0, PAGE_CACHE_SIZE);
+ SetPageUptodate(page);
+ return 0;
+ }
+
+ 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;
+ }
+
+ err = ceph_readpage_from_fscache(inode, page);
+ if (err == 0)
+ goto out;
+
+ 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,
+ off, &len,
+ ci->i_truncate_seq, ci->i_truncate_size,
+ &page, 1, 0);
+ if (err == -ENOENT)
+ err = 0;
+ if (err < 0) {
+ SetPageError(page);
+ ceph_fscache_readpage_cancel(inode, page);
+ goto out;
+ }
+ if (err < PAGE_CACHE_SIZE)
+ /* zero fill remainder of page */
+ zero_user_segment(page, err, PAGE_CACHE_SIZE);
+ else
+ flush_dcache_page(page);
+
+ SetPageUptodate(page);
+ ceph_readpage_to_fscache(inode, 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;
+}
+
+/*
+ * Finish an async read(ahead) op.
+ */
+static void finish_read(struct ceph_osd_request *req, struct ceph_msg *msg)
+{
+ struct inode *inode = req->r_inode;
+ struct ceph_osd_data *osd_data;
+ int rc = req->r_result;
+ int bytes = le32_to_cpu(msg->hdr.data_len);
+ int num_pages;
+ int i;
+
+ 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 */
+ osd_data = osd_req_op_extent_osd_data(req, 0);
+ BUG_ON(osd_data->type != CEPH_OSD_DATA_TYPE_PAGES);
+ num_pages = calc_pages_for((u64)osd_data->alignment,
+ (u64)osd_data->length);
+ for (i = 0; i < num_pages; i++) {
+ struct page *page = osd_data->pages[i];
+
+ if (rc < 0)
+ goto unlock;
+ if (bytes < (int)PAGE_CACHE_SIZE) {
+ /* zero (remainder of) page */
+ int s = bytes < 0 ? 0 : bytes;
+ zero_user_segment(page, s, PAGE_CACHE_SIZE);
+ }
+ dout("finish_read %p uptodate %p idx %lu\n", inode, page,
+ page->index);
+ flush_dcache_page(page);
+ SetPageUptodate(page);
+ ceph_readpage_to_fscache(inode, page);
+unlock:
+ unlock_page(page);
+ page_cache_release(page);
+ bytes -= PAGE_CACHE_SIZE;
+ }
+ kfree(osd_data->pages);
+}
+
+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]);
+}
+
+/*
+ * start an async read(ahead) operation. return nr_pages we submitted
+ * a read for on success, or negative error code.
+ */
+static int start_read(struct inode *inode, struct list_head *page_list, int max)
+{
+ struct ceph_osd_client *osdc =
+ &ceph_inode_to_client(inode)->client->osdc;
+ struct ceph_inode_info *ci = ceph_inode(inode);
+ struct page *page = list_entry(page_list->prev, struct page, lru);
+ struct ceph_vino vino;
+ struct ceph_osd_request *req;
+ u64 off;
+ u64 len;
+ int i;
+ struct page **pages;
+ pgoff_t next_index;
+ int nr_pages = 0;
+ int ret;
+
+ off = (u64) page_offset(page);
+
+ /* 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++;
+ if (max && nr_pages == max)
+ break;
+ }
+ len = nr_pages << PAGE_CACHE_SHIFT;
+ dout("start_read %p nr_pages %d is %lld~%lld\n", inode, nr_pages,
+ off, len);
+ vino = ceph_vino(inode);
+ req = ceph_osdc_new_request(osdc, &ci->i_layout, vino, off, &len,
+ 0, 1, CEPH_OSD_OP_READ,
+ CEPH_OSD_FLAG_READ, NULL,
+ ci->i_truncate_seq, ci->i_truncate_size,
+ false);
+ if (IS_ERR(req))
+ return PTR_ERR(req);
+
+ /* build page vector */
+ nr_pages = calc_pages_for(0, len);
+ pages = kmalloc(sizeof(*pages) * nr_pages, GFP_NOFS);
+ 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));
+ list_del(&page->lru);
+
+ 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,
+ GFP_NOFS)) {
+ ceph_fscache_uncache_page(inode, page);
+ page_cache_release(page);
+ dout("start_read %p add_to_page_cache failed %p\n",
+ inode, page);
+ nr_pages = i;
+ goto out_pages;
+ }
+ pages[i] = page;
+ }
+ osd_req_op_extent_osd_data_pages(req, 0, pages, len, 0, false, false);
+ req->r_callback = finish_read;
+ req->r_inode = inode;
+
+ ceph_osdc_build_request(req, off, NULL, vino.snap, NULL);
+
+ 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:
+ ceph_unlock_page_vector(pages, nr_pages);
+ ceph_release_page_vector(pages, nr_pages);
+out:
+ ceph_osdc_put_request(req);
+ return ret;
+}
+
+
+/*
+ * 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_inode(file);
+ struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
+ int rc = 0;
+ int max = 0;
+
+ if (ceph_inode(inode)->i_inline_version != CEPH_INLINE_NONE)
+ return -EINVAL;
+
+ rc = ceph_readpages_from_fscache(mapping->host, mapping, page_list,
+ &nr_pages);
+
+ if (rc == 0)
+ goto out;
+
+ if (fsc->mount_options->rsize >= PAGE_CACHE_SIZE)
+ max = (fsc->mount_options->rsize + PAGE_CACHE_SIZE - 1)
+ >> PAGE_SHIFT;
+
+ dout("readpages %p file %p nr_pages %d max %d\n", inode,
+ file, nr_pages,
+ max);
+ while (!list_empty(page_list)) {
+ rc = start_read(inode, page_list, max);
+ if (rc < 0)
+ goto out;
+ BUG_ON(rc == 0);
+ }
+out:
+ ceph_fscache_readpages_cancel(inode, page_list);
+
+ dout("readpages %p file %p ret %d\n", inode, file, rc);
+ 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.
+ */
+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;
+
+ spin_lock(&ci->i_ceph_lock);
+ 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_wrbuffer_ref_head) {
+ snapc = ceph_get_snap_context(ci->i_head_snapc);
+ dout(" head snapc %p has %d dirty pages\n",
+ snapc, ci->i_wrbuffer_ref_head);
+ }
+ spin_unlock(&ci->i_ceph_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_fs_client *fsc;
+ struct ceph_osd_client *osdc;
+ struct ceph_snap_context *snapc, *oldest;
+ loff_t page_off = page_offset(page);
+ long writeback_stat;
+ u64 truncate_size, snap_size = 0;
+ u32 truncate_seq;
+ int err = 0, len = PAGE_CACHE_SIZE;
+
+ 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);
+ fsc = ceph_inode_to_client(inode);
+ osdc = &fsc->client->osdc;
+
+ /* verify this is a writeable snap context */
+ snapc = page_snap_context(page);
+ if (snapc == NULL) {
+ dout("writepage %p page %p not dirty?\n", inode, page);
+ goto out;
+ }
+ oldest = get_oldest_context(inode, &snap_size);
+ if (snapc->seq > oldest->seq) {
+ dout("writepage %p page %p snapc %p not writeable - noop\n",
+ inode, page, snapc);
+ /* we should only noop if called by kswapd */
+ WARN_ON((current->flags & PF_MEMALLOC) == 0);
+ ceph_put_snap_context(oldest);
+ goto out;
+ }
+ ceph_put_snap_context(oldest);
+
+ spin_lock(&ci->i_ceph_lock);
+ truncate_seq = ci->i_truncate_seq;
+ truncate_size = ci->i_truncate_size;
+ if (!snap_size)
+ snap_size = i_size_read(inode);
+ spin_unlock(&ci->i_ceph_lock);
+
+ /* is this a partial page at end of file? */
+ 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;
+
+ dout("writepage %p page %p index %lu on %llu~%u snapc %p\n",
+ inode, page, page->index, page_off, len, snapc);
+
+ writeback_stat = atomic_long_inc_return(&fsc->writeback_count);
+ if (writeback_stat >
+ CONGESTION_ON_THRESH(fsc->mount_options->congestion_kb))
+ set_bdi_congested(&fsc->backing_dev_info, BLK_RW_ASYNC);
+
+ ceph_readpage_to_fscache(inode, page);
+
+ set_page_writeback(page);
+ err = ceph_osdc_writepages(osdc, ceph_vino(inode),
+ &ci->i_layout, snapc,
+ page_off, len,
+ truncate_seq, truncate_size,
+ &inode->i_mtime, &page, 1);
+ 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); /* page's reference */
+out:
+ return err;
+}
+
+static int ceph_writepage(struct page *page, struct writeback_control *wbc)
+{
+ int err;
+ struct inode *inode = page->mapping->host;
+ BUG_ON(!inode);
+ ihold(inode);
+ err = writepage_nounlock(page, wbc);
+ unlock_page(page);
+ iput(inode);
+ 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);
+ struct ceph_osd_data *osd_data;
+ unsigned wrote;
+ struct page *page;
+ int num_pages;
+ int i;
+ struct ceph_snap_context *snapc = req->r_snapc;
+ struct address_space *mapping = inode->i_mapping;
+ int rc = req->r_result;
+ u64 bytes = req->r_ops[0].extent.length;
+ struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
+ long writeback_stat;
+ unsigned issued = ceph_caps_issued(ci);
+
+ osd_data = osd_req_op_extent_osd_data(req, 0);
+ BUG_ON(osd_data->type != CEPH_OSD_DATA_TYPE_PAGES);
+ num_pages = calc_pages_for((u64)osd_data->alignment,
+ (u64)osd_data->length);
+ if (rc >= 0) {
+ /*
+ * 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 = 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 < num_pages; i++) {
+ page = osd_data->pages[i];
+ BUG_ON(!page);
+ WARN_ON(!PageUptodate(page));
+
+ writeback_stat =
+ atomic_long_dec_return(&fsc->writeback_count);
+ if (writeback_stat <
+ 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 %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|CEPH_CAP_FILE_LAZYIO)) == 0)
+ generic_error_remove_page(inode->i_mapping, page);
+
+ unlock_page(page);
+ }
+ dout("%p wrote+cleaned %d pages\n", inode, wrote);
+ ceph_put_wrbuffer_cap_refs(ci, num_pages, snapc);
+
+ ceph_release_pages(osd_data->pages, num_pages);
+ if (osd_data->pages_from_pool)
+ mempool_free(osd_data->pages,
+ ceph_sb_to_client(inode->i_sb)->wb_pagevec_pool);
+ else
+ kfree(osd_data->pages);
+ 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);
+ struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
+ struct ceph_vino vino = ceph_vino(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, *pgsnapc;
+ struct pagevec pvec;
+ int done = 0;
+ int rc = 0;
+ unsigned wsize = 1 << inode->i_blkbits;
+ struct ceph_osd_request *req = NULL;
+ int do_sync = 0;
+ u64 truncate_size, snap_size;
+ u32 truncate_seq;
+
+ /*
+ * 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.
+ */
+ if ((wbc->sync_mode == WB_SYNC_ALL) ||
+ 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"));
+
+ if (fsc->mount_state == CEPH_MOUNT_SHUTDOWN) {
+ pr_warn("writepage_start %p on forced umount\n", inode);
+ return -EIO; /* we're in a forced umount, don't write! */
+ }
+ if (fsc->mount_options->wsize && fsc->mount_options->wsize < wsize)
+ wsize = fsc->mount_options->wsize;
+ 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);
+ snap_size = 0;
+ 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;
+ }
+ if (snap_size == 0)
+ snap_size = i_size_read(inode);
+ dout(" oldest snapc is %p seq %lld (%d snaps)\n",
+ snapc, snapc->seq, snapc->num_snaps);
+
+ spin_lock(&ci->i_ceph_lock);
+ truncate_seq = ci->i_truncate_seq;
+ truncate_size = ci->i_truncate_size;
+ if (!snap_size)
+ snap_size = i_size_read(inode);
+ spin_unlock(&ci->i_ceph_lock);
+
+ 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 **pages = NULL;
+ mempool_t *pool = NULL; /* Becomes non-null if mempool used */
+ struct page *page;
+ int want;
+ u64 offset, len;
+ long writeback_stat;
+
+ 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 (page_offset(page) >= snap_size) {
+ dout("%p page eof %llu\n", page, snap_size);
+ done = 1;
+ unlock_page(page);
+ break;
+ }
+ if (PageWriteback(page)) {
+ dout("%p under writeback\n", page);
+ unlock_page(page);
+ break;
+ }
+
+ /* only if matching snap context */
+ pgsnapc = page_snap_context(page);
+ if (pgsnapc->seq > snapc->seq) {
+ dout("page snapc %p %lld > oldest %p %lld\n",
+ pgsnapc, pgsnapc->seq, snapc, snapc->seq);
+ 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;
+ }
+
+ /*
+ * We have something to write. If this is
+ * the first locked page this time through,
+ * allocate an osd request and a page array
+ * that it will use.
+ */
+ if (locked_pages == 0) {
+ BUG_ON(pages);
+ /* prepare async write request */
+ offset = (u64)page_offset(page);
+ len = wsize;
+ req = ceph_osdc_new_request(&fsc->client->osdc,
+ &ci->i_layout, vino,
+ offset, &len, 0,
+ do_sync ? 2 : 1,
+ CEPH_OSD_OP_WRITE,
+ CEPH_OSD_FLAG_WRITE |
+ CEPH_OSD_FLAG_ONDISK,
+ snapc, truncate_seq,
+ truncate_size, true);
+ if (IS_ERR(req)) {
+ rc = PTR_ERR(req);
+ unlock_page(page);
+ break;
+ }
+
+ if (do_sync)
+ osd_req_op_init(req, 1, CEPH_OSD_OP_STARTSYNC);
+
+ req->r_callback = writepages_finish;
+ req->r_inode = inode;
+
+ max_pages = calc_pages_for(0, (u64)len);
+ pages = kmalloc(max_pages * sizeof (*pages),
+ GFP_NOFS);
+ if (!pages) {
+ pool = fsc->wb_pagevec_pool;
+ pages = mempool_alloc(pool, GFP_NOFS);
+ BUG_ON(!pages);
+ }
+ }
+
+ /* 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);
+
+ writeback_stat =
+ atomic_long_inc_return(&fsc->writeback_count);
+ if (writeback_stat > CONGESTION_ON_THRESH(
+ fsc->mount_options->congestion_kb)) {
+ set_bdi_congested(&fsc->backing_dev_info,
+ BLK_RW_ASYNC);
+ }
+
+ set_page_writeback(page);
+ 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;
+ }
+
+ /* Format the osd request message and submit the write */
+
+ offset = page_offset(pages[0]);
+ len = min(snap_size - offset,
+ (u64)locked_pages << PAGE_CACHE_SHIFT);
+ dout("writepages got %d pages at %llu~%llu\n",
+ locked_pages, offset, len);
+
+ osd_req_op_extent_osd_data_pages(req, 0, pages, len, 0,
+ !!pool, false);
+
+ pages = NULL; /* request message now owns the pages array */
+ pool = NULL;
+
+ /* Update the write op length in case we changed it */
+
+ osd_req_op_extent_update(req, 0, len);
+
+ vino = ceph_vino(inode);
+ ceph_osdc_build_request(req, offset, snapc, vino.snap,
+ &inode->i_mtime);
+
+ rc = ceph_osdc_start_request(&fsc->client->osdc, req, true);
+ BUG_ON(rc);
+ 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);
+ 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);
+ int ret = !oldest || snapc->seq <= oldest->seq;
+
+ ceph_put_snap_context(oldest);
+ return ret;
+}
+
+/*
+ * We are only allowed to write into/dirty the page if the page is
+ * clean, or already dirty within the same snap context.
+ *
+ * called with page locked.
+ * return success with page locked,
+ * or any failure (incl -EAGAIN) with page unlocked.
+ */
+static int ceph_update_writeable_page(struct file *file,
+ loff_t pos, unsigned len,
+ struct page *page)
+{
+ struct inode *inode = file_inode(file);
+ struct ceph_inode_info *ci = ceph_inode(inode);
+ struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
+ 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;
+ struct ceph_snap_context *snapc, *oldest;
+
+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);
+ snapc = page_snap_context(page);
+ if (snapc && snapc != ci->i_head_snapc) {
+ /*
+ * this page is already dirty in another (older) snap
+ * context! is it writeable now?
+ */
+ oldest = get_oldest_context(inode, NULL);
+ up_read(&mdsc->snap_rwsem);
+
+ if (snapc->seq > oldest->seq) {
+ ceph_put_snap_context(oldest);
+ dout(" page %p snapc %p not current or oldest\n",
+ page, snapc);
+ /*
+ * queue for writeback, and wait for snapc to
+ * be writeable or written
+ */
+ snapc = ceph_get_snap_context(snapc);
+ unlock_page(page);
+ ceph_queue_writeback(inode);
+ r = wait_event_interruptible(ci->i_cap_wq,
+ context_is_writeable_or_written(inode, snapc));
+ ceph_put_snap_context(snapc);
+ if (r == -ERESTARTSYS)
+ return r;
+ return -EAGAIN;
+ }
+ ceph_put_snap_context(oldest);
+
+ /* 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 (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_nosnap:
+ unlock_page(page);
+ 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_inode(file);
+ 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);
+ if (r < 0)
+ page_cache_release(page);
+ else
+ *pagep = 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
+ * 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_inode(file);
+ struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
+ struct ceph_mds_client *mdsc = fsc->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(struct kiocb *iocb, struct iov_iter *iter,
+ loff_t pos)
+{
+ 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
+ */
+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;
+ struct page *pinned_page = NULL;
+ 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",
+ inode, ceph_vinop(inode), off, (size_t)PAGE_CACHE_SIZE);
+ 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;
+ ret = ceph_get_caps(ci, CEPH_CAP_FILE_RD, want,
+ -1, &got, &pinned_page);
+ 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",
+ inode, off, (size_t)PAGE_CACHE_SIZE, ceph_cap_string(got));
+
+ 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;
+
+ dout("filemap_fault %p %llu~%zd dropping cap refs on %s ret %d\n",
+ inode, off, (size_t)PAGE_CACHE_SIZE, ceph_cap_string(got), ret);
+ if (pinned_page)
+ page_cache_release(pinned_page);
+ ceph_put_cap_refs(ci, got);
+
+ 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,
+ mapping_gfp_mask(mapping) &
+ ~__GFP_FS);
+ 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);
+ return ret;
+}
+
+/*
+ * Reuse write_begin here for simplicity.
+ */
+static int ceph_page_mkwrite(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;
+ struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
+ struct page *page = vmf->page;
+ loff_t off = page_offset(page);
+ loff_t size = i_size_read(inode);
+ size_t len;
+ int want, got, ret;
+
+ 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);
+ if (ret < 0)
+ return VM_FAULT_SIGBUS;
+ }
+
+ if (off + PAGE_CACHE_SIZE <= size)
+ len = PAGE_CACHE_SIZE;
+ else
+ len = size & ~PAGE_CACHE_MASK;
+
+ 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;
+ ret = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, off + len,
+ &got, NULL);
+ if (ret == 0)
+ break;
+ if (ret != -ERESTARTSYS) {
+ WARN_ON(1);
+ return VM_FAULT_SIGBUS;
+ }
+ }
+ 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);
+
+ 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);
+ ret = VM_FAULT_LOCKED;
+ } else {
+ if (ret == -ENOMEM)
+ ret = VM_FAULT_OOM;
+ else
+ ret = VM_FAULT_SIGBUS;
+ }
+out:
+ if (ret != VM_FAULT_LOCKED)
+ unlock_page(page);
+ if (ret == VM_FAULT_LOCKED ||
+ ci->i_inline_version != CEPH_INLINE_NONE) {
+ int dirty;
+ spin_lock(&ci->i_ceph_lock);
+ ci->i_inline_version = CEPH_INLINE_NONE;
+ dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR);
+ 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);
+
+ return ret;
+}
+
+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,
+ mapping_gfp_mask(mapping) & ~__GFP_FS);
+ if (!page)
+ return;
+ if (PageUptodate(page)) {
+ unlock_page(page);
+ page_cache_release(page);
+ return;
+ }
+ }
+
+ dout("fill_inline_data %p %llx.%llx len %zu locked_page %p\n",
+ 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);
+ }
+}
+
+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,
+ ci->i_snap_realm->cached_context,
+ 0, 0, false);
+ 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,
+ ci->i_snap_realm->cached_context,
+ ci->i_truncate_seq, ci->i_truncate_size,
+ false);
+ if (IS_ERR(req)) {
+ err = PTR_ERR(req);
+ goto out;
+ }
+
+ osd_req_op_extent_osd_data_pages(req, 1, &page, len, 0, false, false);
+
+ {
+ __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;
+ }
+
+ 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;
+}
+
+static struct vm_operations_struct ceph_vmops = {
+ .fault = ceph_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;
+ return 0;
+}