Create a new ceph_fscache_req structure that holds a fscache_io_request and a refcount_t. Change the readpage code to use the new infrastructure. Have KConfig select CONFIG_FSCACHE_SERVICES and CONFIG_FSCACHE_READ_HELPER so that this will still work even when FSCache proper is disabled.
Signed-off-by: Jeff Layton <[email protected]> --- fs/ceph/Kconfig | 2 + fs/ceph/addr.c | 204 +++++++++++++++++++++++++++++++++++++++++++++--- 2 files changed, 196 insertions(+), 10 deletions(-) diff --git a/fs/ceph/Kconfig b/fs/ceph/Kconfig index e955a38be3c8..432aa34b63e7 100644 --- a/fs/ceph/Kconfig +++ b/fs/ceph/Kconfig @@ -6,6 +6,8 @@ config CEPH_FS select LIBCRC32C select CRYPTO_AES select CRYPTO + select FSCACHE_SERVICES + select FSCACHE_READ_HELPER default n help Choose Y or M here to include support for mounting the diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c index e005c32270f5..75cdd35f1d2e 100644 --- a/fs/ceph/addr.c +++ b/fs/ceph/addr.c @@ -12,6 +12,7 @@ #include <linux/signal.h> #include <linux/iversion.h> #include <linux/ktime.h> +#include <linux/fscache.h> #include "super.h" #include "mds_client.h" @@ -182,6 +183,199 @@ static int ceph_releasepage(struct page *page, gfp_t g) return 1; } +struct ceph_fscache_req { + struct fscache_io_request fscache_req; + refcount_t ref; +}; + +static struct ceph_fscache_req *ceph_fsreq_alloc(void) +{ + struct ceph_fscache_req *req = kzalloc(sizeof(*req), GFP_NOFS); + + if (req) + refcount_set(&req->ref, 1); + return req; +} + +static void ceph_fsreq_done(struct fscache_io_request *fsreq) +{ +} + +static void ceph_fsreq_get(struct fscache_io_request *fsreq) +{ + struct ceph_fscache_req *req = container_of(fsreq, struct ceph_fscache_req, fscache_req); + + refcount_inc(&req->ref); +} + +static void ceph_fsreq_put(struct fscache_io_request *fsreq) +{ + struct ceph_fscache_req *req = container_of(fsreq, struct ceph_fscache_req, fscache_req); + + if (refcount_dec_and_test(&req->ref)) { + fscache_free_io_request(fsreq); + kfree(req); + } +} + +static void ceph_fsreq_reshape(struct fscache_io_request *fsreq, + struct fscache_request_shape *shape) +{ + struct inode *inode = fsreq->mapping->host; + struct ceph_inode_info *ci = ceph_inode(inode); + u64 objno, objoff; + u32 xlen; + + /* Truncate the extent at the end of the current object */ + ceph_calc_file_object_mapping(&ci->i_layout, shape->actual_start << PAGE_SHIFT, + shape->actual_nr_pages << PAGE_SHIFT, &objno, &objoff, &xlen); + shape->actual_nr_pages = xlen >> PAGE_SHIFT; +} + +static void finish_fsreq_read(struct ceph_osd_request *req) +{ + struct ceph_fs_client *fsc = ceph_inode_to_client(req->r_inode); + struct ceph_osd_data *osd_data = osd_req_op_extent_osd_data(req, 0); + struct fscache_io_request *fsreq = req->r_priv; + int num_pages; + int err = req->r_result; + + ceph_update_read_latency(&fsc->mdsc->metric, req->r_start_latency, + req->r_end_latency, err); + + /* no object means success but no data */ + if (err == -ENOENT) + err = 0; + else if (err == -EBLACKLISTED) + fsc->blacklisted = true; + + dout("%s: result %d\n", __func__, err); + if (err >= 0) + fsreq->transferred = err; + else + fsreq->error = err; + + if (fsreq->io_done) + fsreq->io_done(fsreq); + + num_pages = calc_pages_for(osd_data->alignment, osd_data->length); + ceph_put_page_vector(osd_data->pages, num_pages, false); + ceph_fsreq_put(fsreq); + iput(req->r_inode); +} + +static void ceph_fsreq_issue_op(struct fscache_io_request *fsreq) +{ + struct inode *inode = fsreq->mapping->host; + struct ceph_inode_info *ci = ceph_inode(inode); + struct ceph_fs_client *fsc = ceph_inode_to_client(inode); + struct ceph_osd_request *req = NULL; + struct ceph_vino vino = ceph_vino(inode); + struct iov_iter iter; + struct page **pages; + size_t page_off; + int err = 0; + u64 len = fsreq->len; + + req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout, vino, fsreq->pos, &len, + 0, 1, CEPH_OSD_OP_READ, + CEPH_OSD_FLAG_READ | fsc->client->osdc.client->options->read_from_replica, + NULL, ci->i_truncate_seq, ci->i_truncate_size, false); + if (IS_ERR(req)) { + err = PTR_ERR(req); + goto out; + } + + dout("%s: pos=%llu orig_len=%llu len=%llu\n", __func__, fsreq->pos, fsreq->len, len); + iov_iter_mapping(&iter, READ, fsreq->mapping, fsreq->pos, len); + len = iov_iter_get_pages_alloc(&iter, &pages, len, &page_off); + if (len < 0) { + err = len; + dout("%s: iov_ter_get_pages_alloc returned %d\n", __func__, err); + goto out; + } + + /* fscache should always give us a page-aligned read */ + WARN_ON_ONCE(page_off); + + osd_req_op_extent_osd_data_pages(req, 0, pages, len, 0, false, false); + req->r_callback = finish_fsreq_read; + req->r_priv = fsreq; + ceph_fsreq_get(fsreq); + req->r_inode = inode; + ihold(inode); + + err = ceph_osdc_start_request(req->r_osdc, req, false); + if (err) { + iput(inode); + ceph_fsreq_put(fsreq); + } +out: + if (req) + ceph_osdc_put_request(req); + + if (err) { + fsreq->error = err; + if (fsreq->io_done) + fsreq->io_done(fsreq); + } + dout("%s: result %d\n", __func__, fsreq->error); +} + +const struct fscache_io_request_ops ceph_readpage_fsreq_ops = { + .issue_op = ceph_fsreq_issue_op, + .reshape = ceph_fsreq_reshape, + .done = ceph_fsreq_done, + .get = ceph_fsreq_get, + .put = ceph_fsreq_put, +}; + +/* read a single page, without unlocking it. */ +static int ceph_readpage(struct file *filp, struct page *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_fscache_req *req; + struct ceph_vino vino = ceph_vino(inode); + struct fscache_cookie *cookie = ceph_fscache_cookie(ci); + int err = 0; + u64 off = page_offset(page); + u64 len = PAGE_SIZE; + + 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) { + unlock_page(page); + return -EINVAL; + } + zero_user_segment(page, 0, PAGE_SIZE); + SetPageUptodate(page); + unlock_page(page); + return 0; + } + + dout("readpage ino %llx.%llx file %p off %llu len %llu page %p index %lu\n", + vino.ino, vino.snap, filp, off, len, page, page->index); + + req = ceph_fsreq_alloc(); + if (!req) { + unlock_page(page); + return -ENOMEM; + } + + fscache_init_io_request(&req->fscache_req, cookie, &ceph_readpage_fsreq_ops); + req->fscache_req.mapping = inode->i_mapping; + + err = fscache_read_helper_locked_page(&req->fscache_req, page, + fsc->mount_options->rsize >> PAGE_SHIFT); + ceph_fsreq_put(&req->fscache_req); + return err; +} + /* read a single page, without unlocking it. */ static int ceph_do_readpage(struct file *filp, struct page *page) { @@ -253,16 +447,6 @@ static int ceph_do_readpage(struct file *filp, struct page *page) return err < 0 ? err : 0; } -static int ceph_readpage(struct file *filp, struct page *page) -{ - int r = ceph_do_readpage(filp, page); - if (r != -EINPROGRESS) - unlock_page(page); - else - r = 0; - return r; -} - /* * Finish an async read(ahead) op. */ -- 2.26.2 -- Linux-cachefs mailing list [email protected] https://www.redhat.com/mailman/listinfo/linux-cachefs
