From 54008399dc0ce511a07b87f1af3d1f5c791982a4 Mon Sep 17 00:00:00 2001 From: "Yan, Zheng" Date: Sat, 29 Mar 2014 13:41:15 +0800 Subject: ceph: preallocate buffer for readdir reply Preallocate buffer for readdir reply. Limit number of entries in readdir reply according to the buffer size. Signed-off-by: Yan, Zheng --- fs/ceph/mds_client.c | 66 ++++++++++++++++++++++++++++++++++++++++------------ 1 file changed, 51 insertions(+), 15 deletions(-) (limited to 'fs/ceph/mds_client.c') diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c index 77640ada487..19fbfc49613 100644 --- a/fs/ceph/mds_client.c +++ b/fs/ceph/mds_client.c @@ -3,6 +3,7 @@ #include #include #include +#include #include #include #include @@ -165,21 +166,18 @@ static int parse_reply_info_dir(void **p, void *end, if (num == 0) goto done; - /* alloc large array */ - info->dir_nr = num; - info->dir_in = kcalloc(num, sizeof(*info->dir_in) + - sizeof(*info->dir_dname) + - sizeof(*info->dir_dname_len) + - sizeof(*info->dir_dlease), - GFP_NOFS); - if (info->dir_in == NULL) { - err = -ENOMEM; - goto out_bad; - } + BUG_ON(!info->dir_in); info->dir_dname = (void *)(info->dir_in + num); info->dir_dname_len = (void *)(info->dir_dname + num); info->dir_dlease = (void *)(info->dir_dname_len + num); + if ((unsigned long)(info->dir_dlease + num) > + (unsigned long)info->dir_in + info->dir_buf_size) { + pr_err("dir contents are larger than expected\n"); + WARN_ON(1); + goto bad; + } + info->dir_nr = num; while (num) { /* dentry */ ceph_decode_need(p, end, sizeof(u32)*2, bad); @@ -327,7 +325,9 @@ out_bad: static void destroy_reply_info(struct ceph_mds_reply_info_parsed *info) { - kfree(info->dir_in); + if (!info->dir_in) + return; + free_pages((unsigned long)info->dir_in, get_order(info->dir_buf_size)); } @@ -512,12 +512,11 @@ void ceph_mdsc_release_request(struct kref *kref) struct ceph_mds_request *req = container_of(kref, struct ceph_mds_request, r_kref); + destroy_reply_info(&req->r_reply_info); if (req->r_request) ceph_msg_put(req->r_request); - if (req->r_reply) { + if (req->r_reply) ceph_msg_put(req->r_reply); - destroy_reply_info(&req->r_reply_info); - } if (req->r_inode) { ceph_put_cap_refs(ceph_inode(req->r_inode), CEPH_CAP_PIN); iput(req->r_inode); @@ -1496,6 +1495,43 @@ static void discard_cap_releases(struct ceph_mds_client *mdsc, * requests */ +int ceph_alloc_readdir_reply_buffer(struct ceph_mds_request *req, + struct inode *dir) +{ + struct ceph_inode_info *ci = ceph_inode(dir); + struct ceph_mds_reply_info_parsed *rinfo = &req->r_reply_info; + struct ceph_mount_options *opt = req->r_mdsc->fsc->mount_options; + size_t size = sizeof(*rinfo->dir_in) + sizeof(*rinfo->dir_dname_len) + + sizeof(*rinfo->dir_dname) + sizeof(*rinfo->dir_dlease); + int order, num_entries; + + spin_lock(&ci->i_ceph_lock); + num_entries = ci->i_files + ci->i_subdirs; + spin_unlock(&ci->i_ceph_lock); + num_entries = max(num_entries, 1); + num_entries = min(num_entries, opt->max_readdir); + + order = get_order(size * num_entries); + while (order >= 0) { + rinfo->dir_in = (void*)__get_free_pages(GFP_NOFS | __GFP_NOWARN, + order); + if (rinfo->dir_in) + break; + order--; + } + if (!rinfo->dir_in) + return -ENOMEM; + + num_entries = (PAGE_SIZE << order) / size; + num_entries = min(num_entries, opt->max_readdir); + + rinfo->dir_buf_size = PAGE_SIZE << order; + req->r_num_caps = num_entries + 1; + req->r_args.readdir.max_entries = cpu_to_le32(num_entries); + req->r_args.readdir.max_bytes = cpu_to_le32(opt->max_readdir_bytes); + return 0; +} + /* * Create an mds request. */ -- cgit v1.2.3-18-g5258