From 4f32b42dca660208c7556e13ebd84c510ad91840 Mon Sep 17 00:00:00 2001 From: "Yan, Zheng" Date: Sat, 1 Mar 2014 18:05:41 +0800 Subject: [PATCH] ceph: simplify ceph_fh_to_dentry() MDS handles LOOKUPHASH and LOOKUPINO MDS requests in the same way. So __cfh_to_dentry() is redundant. Signed-off-by: Yan, Zheng Reviewed-by: Sage Weil --- fs/ceph/export.c | 167 +++++++++-------------------------------------- 1 file changed, 32 insertions(+), 135 deletions(-) diff --git a/fs/ceph/export.c b/fs/ceph/export.c index 16796be53ca5..976d3411d5ed 100644 --- a/fs/ceph/export.c +++ b/fs/ceph/export.c @@ -7,23 +7,6 @@ #include "super.h" #include "mds_client.h" -/* - * NFS export support - * - * NFS re-export of a ceph mount is, at present, only semireliable. - * The basic issue is that the Ceph architectures doesn't lend itself - * well to generating filehandles that will remain valid forever. - * - * So, we do our best. If you're lucky, your inode will be in the - * client's cache. If it's not, and you have a connectable fh, then - * the MDS server may be able to find it for you. Otherwise, you get - * ESTALE. - * - * There are ways to this more reliable, but in the non-connectable fh - * case, we won't every work perfectly, and in the connectable case, - * some changes are needed on the MDS side to work better. - */ - /* * Basic fh */ @@ -32,22 +15,12 @@ struct ceph_nfs_fh { } __attribute__ ((packed)); /* - * Larger 'connectable' fh that includes parent ino and name hash. - * Use this whenever possible, as it works more reliably. + * Larger fh that includes parent ino. */ struct ceph_nfs_confh { u64 ino, parent_ino; - u32 parent_name_hash; } __attribute__ ((packed)); -/* - * The presence of @parent_inode here tells us whether NFS wants a - * connectable file handle. However, we want to make a connectionable - * file handle unconditionally so that the MDS gets as much of a hint - * as possible. That means we only use @parent_dentry to indicate - * whether nfsd wants a connectable fh, and whether we should indicate - * failure from a too-small @max_len. - */ static int ceph_encode_fh(struct inode *inode, u32 *rawfh, int *max_len, struct inode *parent_inode) { @@ -56,54 +29,36 @@ static int ceph_encode_fh(struct inode *inode, u32 *rawfh, int *max_len, struct ceph_nfs_confh *cfh = (void *)rawfh; int connected_handle_length = sizeof(*cfh)/4; int handle_length = sizeof(*fh)/4; - struct dentry *dentry; - struct dentry *parent; /* don't re-export snaps */ if (ceph_snap(inode) != CEPH_NOSNAP) return -EINVAL; - dentry = d_find_alias(inode); + if (parent_inode && (*max_len < connected_handle_length)) { + *max_len = connected_handle_length; + return FILEID_INVALID; + } else if (*max_len < handle_length) { + *max_len = handle_length; + return FILEID_INVALID; + } - /* if we found an alias, generate a connectable fh */ - if (*max_len >= connected_handle_length && dentry) { - dout("encode_fh %p connectable\n", dentry); - spin_lock(&dentry->d_lock); - parent = dentry->d_parent; + if (parent_inode) { + dout("encode_fh %llx with parent %llx\n", + ceph_ino(inode), ceph_ino(parent_inode)); cfh->ino = ceph_ino(inode); - cfh->parent_ino = ceph_ino(parent->d_inode); - cfh->parent_name_hash = ceph_dentry_hash(parent->d_inode, - dentry); + cfh->parent_ino = ceph_ino(parent_inode); *max_len = connected_handle_length; - type = 2; - spin_unlock(&dentry->d_lock); - } else if (*max_len >= handle_length) { - if (parent_inode) { - /* nfsd wants connectable */ - *max_len = connected_handle_length; - type = FILEID_INVALID; - } else { - dout("encode_fh %p\n", dentry); - fh->ino = ceph_ino(inode); - *max_len = handle_length; - type = 1; - } + type = FILEID_INO32_GEN_PARENT; } else { + dout("encode_fh %llx\n", ceph_ino(inode)); + fh->ino = ceph_ino(inode); *max_len = handle_length; - type = FILEID_INVALID; + type = FILEID_INO32_GEN; } - if (dentry) - dput(dentry); return type; } -/* - * convert regular fh to dentry - * - * FIXME: we should try harder by querying the mds for the ino. - */ -static struct dentry *__fh_to_dentry(struct super_block *sb, - struct ceph_nfs_fh *fh, int fh_len) +static struct dentry *__fh_to_dentry(struct super_block *sb, u64 ino) { struct ceph_mds_client *mdsc = ceph_sb_to_client(sb)->mdsc; struct inode *inode; @@ -111,11 +66,7 @@ static struct dentry *__fh_to_dentry(struct super_block *sb, struct ceph_vino vino; int err; - if (fh_len < sizeof(*fh) / 4) - return ERR_PTR(-ESTALE); - - dout("__fh_to_dentry %llx\n", fh->ino); - vino.ino = fh->ino; + vino.ino = ino; vino.snap = CEPH_NOSNAP; inode = ceph_find_inode(sb, vino); if (!inode) { @@ -139,89 +90,35 @@ static struct dentry *__fh_to_dentry(struct super_block *sb, dentry = d_obtain_alias(inode); if (IS_ERR(dentry)) { - pr_err("fh_to_dentry %llx -- inode %p but ENOMEM\n", - fh->ino, inode); iput(inode); return dentry; } err = ceph_init_dentry(dentry); if (err < 0) { - iput(inode); + dput(dentry); return ERR_PTR(err); } - dout("__fh_to_dentry %llx %p dentry %p\n", fh->ino, inode, dentry); + dout("__fh_to_dentry %llx %p dentry %p\n", ino, inode, dentry); return dentry; } /* - * convert connectable fh to dentry + * convert regular fh to dentry */ -static struct dentry *__cfh_to_dentry(struct super_block *sb, - struct ceph_nfs_confh *cfh, int fh_len) +static struct dentry *ceph_fh_to_dentry(struct super_block *sb, + struct fid *fid, + int fh_len, int fh_type) { - struct ceph_mds_client *mdsc = ceph_sb_to_client(sb)->mdsc; - struct inode *inode; - struct dentry *dentry; - struct ceph_vino vino; - int err; - - if (fh_len < sizeof(*cfh) / 4) - return ERR_PTR(-ESTALE); - - dout("__cfh_to_dentry %llx (%llx/%x)\n", - cfh->ino, cfh->parent_ino, cfh->parent_name_hash); - - vino.ino = cfh->ino; - vino.snap = CEPH_NOSNAP; - inode = ceph_find_inode(sb, vino); - if (!inode) { - struct ceph_mds_request *req; - - req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPHASH, - USE_ANY_MDS); - if (IS_ERR(req)) - return ERR_CAST(req); - - req->r_ino1 = vino; - req->r_ino2.ino = cfh->parent_ino; - req->r_ino2.snap = CEPH_NOSNAP; - req->r_path2 = kmalloc(16, GFP_NOFS); - snprintf(req->r_path2, 16, "%d", cfh->parent_name_hash); - req->r_num_caps = 1; - err = ceph_mdsc_do_request(mdsc, NULL, req); - inode = req->r_target_inode; - if (inode) - ihold(inode); - ceph_mdsc_put_request(req); - if (!inode) - return ERR_PTR(err ? err : -ESTALE); - } + struct ceph_nfs_fh *fh = (void *)fid->raw; - dentry = d_obtain_alias(inode); - if (IS_ERR(dentry)) { - pr_err("cfh_to_dentry %llx -- inode %p but ENOMEM\n", - cfh->ino, inode); - iput(inode); - return dentry; - } - err = ceph_init_dentry(dentry); - if (err < 0) { - iput(inode); - return ERR_PTR(err); - } - dout("__cfh_to_dentry %llx %p dentry %p\n", cfh->ino, inode, dentry); - return dentry; -} + if (fh_type != FILEID_INO32_GEN && + fh_type != FILEID_INO32_GEN_PARENT) + return NULL; + if (fh_len < sizeof(*fh) / 4) + return NULL; -static struct dentry *ceph_fh_to_dentry(struct super_block *sb, struct fid *fid, - int fh_len, int fh_type) -{ - if (fh_type == 1) - return __fh_to_dentry(sb, (struct ceph_nfs_fh *)fid->raw, - fh_len); - else - return __cfh_to_dentry(sb, (struct ceph_nfs_confh *)fid->raw, - fh_len); + dout("fh_to_dentry %llx\n", fh->ino); + return __fh_to_dentry(sb, fh->ino); } /* -- 2.30.2