| Message ID | 20200220224935.12541-1-pc@cjr.nz (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/2] cifs: handle prefix paths in reconnect | expand |
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com> On Fri, Feb 21, 2020 at 8:50 AM Paulo Alcantara (SUSE) <pc@cjr.nz> wrote: > > For the case where we have a DFS path like below and we're currently > connected to targetA: > > //dfsroot/link -> //targetA/share/foo, //targetB/share/bar > > after failover, we should make sure to update cifs_sb->prepath so the > next operations will use the new prefix path "/bar". > > Besides, in order to simplify the use of different prefix paths, > enforce CIFS_MOUNT_USE_PREFIX_PATH for DFS mounts so we don't have to > revalidate the root dentry every time we set a new prefix path. > > Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz> > --- > fs/cifs/cifsproto.h | 5 +++ > fs/cifs/cifssmb.c | 19 ++++++++--- > fs/cifs/connect.c | 63 +++++++---------------------------- > fs/cifs/dfs_cache.c | 38 +++++++++++++++++++++ > fs/cifs/dfs_cache.h | 4 +++ > fs/cifs/misc.c | 80 +++++++++++++++++++++++++++++++++++++++++++++ > fs/cifs/smb2pdu.c | 19 ++++++++--- > 7 files changed, 169 insertions(+), 59 deletions(-) > > diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h > index 89eaaf46d1ca..af8e79b58b94 100644 > --- a/fs/cifs/cifsproto.h > +++ b/fs/cifs/cifsproto.h > @@ -601,6 +601,11 @@ int smb2_parse_query_directory(struct cifs_tcon *tcon, struct kvec *rsp_iov, > int resp_buftype, > struct cifs_search_info *srch_inf); > > +struct super_block *cifs_get_tcp_super(struct TCP_Server_Info *server); > +void cifs_put_tcp_super(struct super_block *sb); > +int update_super_prepath(struct cifs_tcon *tcon, const char *prefix, > + size_t prefix_len); > + > #ifdef CONFIG_CIFS_DFS_UPCALL > static inline int get_dfs_path(const unsigned int xid, struct cifs_ses *ses, > const char *old_path, > diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c > index 3c89569e7210..b6fa575d2d3f 100644 > --- a/fs/cifs/cifssmb.c > +++ b/fs/cifs/cifssmb.c > @@ -162,9 +162,18 @@ static int __cifs_reconnect_tcon(const struct nls_table *nlsc, > > for (it = dfs_cache_get_tgt_iterator(&tl); it; > it = dfs_cache_get_next_tgt(&tl, it)) { > - const char *tgt = dfs_cache_get_tgt_name(it); > + const char *share, *prefix; > + size_t share_len, prefix_len; > > - extract_unc_hostname(tgt, &dfs_host, &dfs_host_len); > + rc = dfs_cache_get_tgt_share(it, &share, &share_len, &prefix, > + &prefix_len); > + if (rc) { > + cifs_dbg(VFS, "%s: failed to parse target share %d\n", > + __func__, rc); > + continue; > + } > + > + extract_unc_hostname(share, &dfs_host, &dfs_host_len); > > if (dfs_host_len != tcp_host_len > || strncasecmp(dfs_host, tcp_host, dfs_host_len) != 0) { > @@ -175,11 +184,13 @@ static int __cifs_reconnect_tcon(const struct nls_table *nlsc, > continue; > } > > - scnprintf(tree, MAX_TREE_SIZE, "\\%s", tgt); > + scnprintf(tree, MAX_TREE_SIZE, "\\%.*s", (int)share_len, share); > > rc = CIFSTCon(0, tcon->ses, tree, tcon, nlsc); > - if (!rc) > + if (!rc) { > + rc = update_super_prepath(tcon, prefix, prefix_len); > break; > + } > if (rc == -EREMOTE) > break; > } > diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c > index 4804d1df8c1c..e2196b363765 100644 > --- a/fs/cifs/connect.c > +++ b/fs/cifs/connect.c > @@ -57,7 +57,6 @@ > #include "smb2proto.h" > #include "smbdirect.h" > #include "dns_resolve.h" > -#include "cifsfs.h" > #ifdef CONFIG_CIFS_DFS_UPCALL > #include "dfs_cache.h" > #endif > @@ -389,54 +388,7 @@ static inline int reconn_set_ipaddr(struct TCP_Server_Info *server) > #endif > > #ifdef CONFIG_CIFS_DFS_UPCALL > -struct super_cb_data { > - struct TCP_Server_Info *server; > - struct super_block *sb; > -}; > - > /* These functions must be called with server->srv_mutex held */ > - > -static void super_cb(struct super_block *sb, void *arg) > -{ > - struct super_cb_data *d = arg; > - struct cifs_sb_info *cifs_sb; > - struct cifs_tcon *tcon; > - > - if (d->sb) > - return; > - > - cifs_sb = CIFS_SB(sb); > - tcon = cifs_sb_master_tcon(cifs_sb); > - if (tcon->ses->server == d->server) > - d->sb = sb; > -} > - > -static struct super_block *get_tcp_super(struct TCP_Server_Info *server) > -{ > - struct super_cb_data d = { > - .server = server, > - .sb = NULL, > - }; > - > - iterate_supers_type(&cifs_fs_type, super_cb, &d); > - > - if (unlikely(!d.sb)) > - return ERR_PTR(-ENOENT); > - /* > - * Grab an active reference in order to prevent automounts (DFS links) > - * of expiring and then freeing up our cifs superblock pointer while > - * we're doing failover. > - */ > - cifs_sb_active(d.sb); > - return d.sb; > -} > - > -static inline void put_tcp_super(struct super_block *sb) > -{ > - if (!IS_ERR_OR_NULL(sb)) > - cifs_sb_deactive(sb); > -} > - > static void reconn_inval_dfs_target(struct TCP_Server_Info *server, > struct cifs_sb_info *cifs_sb, > struct dfs_cache_tgt_list *tgt_list, > @@ -508,7 +460,7 @@ cifs_reconnect(struct TCP_Server_Info *server) > server->nr_targets = 1; > #ifdef CONFIG_CIFS_DFS_UPCALL > spin_unlock(&GlobalMid_Lock); > - sb = get_tcp_super(server); > + sb = cifs_get_tcp_super(server); > if (IS_ERR(sb)) { > rc = PTR_ERR(sb); > cifs_dbg(FYI, "%s: will not do DFS failover: rc = %d\n", > @@ -535,7 +487,7 @@ cifs_reconnect(struct TCP_Server_Info *server) > spin_unlock(&GlobalMid_Lock); > #ifdef CONFIG_CIFS_DFS_UPCALL > dfs_cache_free_tgts(&tgt_list); > - put_tcp_super(sb); > + cifs_put_tcp_super(sb); > #endif > return rc; > } else > @@ -666,7 +618,7 @@ cifs_reconnect(struct TCP_Server_Info *server) > > } > > - put_tcp_super(sb); > + cifs_put_tcp_super(sb); > #endif > if (server->tcpStatus == CifsNeedNegotiate) > mod_delayed_work(cifsiod_wq, &server->echo, 0); > @@ -4999,6 +4951,15 @@ int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb_vol *vol) > * dentry revalidation to think the dentry are stale (ESTALE). > */ > cifs_autodisable_serverino(cifs_sb); > + /* > + * Force the use of prefix path to support failover on DFS paths that > + * resolve to targets that have different prefix paths. > + */ > + cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH; > + kfree(cifs_sb->prepath); > + cifs_sb->prepath = vol->prepath; > + vol->prepath = NULL; > + > out: > free_xid(xid); > cifs_try_adding_channels(ses); > diff --git a/fs/cifs/dfs_cache.c b/fs/cifs/dfs_cache.c > index 43c1b43a07ec..a67f88bf7ae1 100644 > --- a/fs/cifs/dfs_cache.c > +++ b/fs/cifs/dfs_cache.c > @@ -1260,6 +1260,44 @@ void dfs_cache_del_vol(const char *fullpath) > kref_put(&vi->refcnt, vol_release); > } > > +/** > + * dfs_cache_get_tgt_share - parse a DFS target > + * > + * @it: DFS target iterator. > + * @share: tree name. > + * @share_len: length of tree name. > + * @prefix: prefix path. > + * @prefix_len: length of prefix path. > + * > + * Return zero if target was parsed correctly, otherwise non-zero. > + */ > +int dfs_cache_get_tgt_share(const struct dfs_cache_tgt_iterator *it, > + const char **share, size_t *share_len, > + const char **prefix, size_t *prefix_len) > +{ > + char *s, sep; > + > + if (!it || !share || !share_len || !prefix || !prefix_len) > + return -EINVAL; > + > + sep = it->it_name[0]; > + if (sep != '\\' && sep != '/') > + return -EINVAL; > + > + s = strchr(it->it_name + 1, sep); > + if (!s) > + return -EINVAL; > + > + s = strchrnul(s + 1, sep); > + > + *share = it->it_name; > + *share_len = s - it->it_name; > + *prefix = *s ? s + 1 : s; > + *prefix_len = &it->it_name[strlen(it->it_name)] - *prefix; > + > + return 0; > +} > + > /* Get all tcons that are within a DFS namespace and can be refreshed */ > static void get_tcons(struct TCP_Server_Info *server, struct list_head *head) > { > diff --git a/fs/cifs/dfs_cache.h b/fs/cifs/dfs_cache.h > index 99ee44f8ad07..bf94d08cfb5a 100644 > --- a/fs/cifs/dfs_cache.h > +++ b/fs/cifs/dfs_cache.h > @@ -49,6 +49,10 @@ extern int dfs_cache_update_vol(const char *fullpath, > struct TCP_Server_Info *server); > extern void dfs_cache_del_vol(const char *fullpath); > > +extern int dfs_cache_get_tgt_share(const struct dfs_cache_tgt_iterator *it, > + const char **share, size_t *share_len, > + const char **prefix, size_t *prefix_len); > + > static inline struct dfs_cache_tgt_iterator * > dfs_cache_get_next_tgt(struct dfs_cache_tgt_list *tl, > struct dfs_cache_tgt_iterator *it) > diff --git a/fs/cifs/misc.c b/fs/cifs/misc.c > index 40ca394fd5de..a456febd4109 100644 > --- a/fs/cifs/misc.c > +++ b/fs/cifs/misc.c > @@ -31,6 +31,7 @@ > #include "nterr.h" > #include "cifs_unicode.h" > #include "smb2pdu.h" > +#include "cifsfs.h" > > extern mempool_t *cifs_sm_req_poolp; > extern mempool_t *cifs_req_poolp; > @@ -1022,3 +1023,82 @@ int copy_path_name(char *dst, const char *src) > name_len++; > return name_len; > } > + > +struct super_cb_data { > + struct TCP_Server_Info *server; > + struct super_block *sb; > +}; > + > +static void super_cb(struct super_block *sb, void *arg) > +{ > + struct super_cb_data *d = arg; > + struct cifs_sb_info *cifs_sb; > + struct cifs_tcon *tcon; > + > + if (d->sb) > + return; > + > + cifs_sb = CIFS_SB(sb); > + tcon = cifs_sb_master_tcon(cifs_sb); > + if (tcon->ses->server == d->server) > + d->sb = sb; > +} > + > +struct super_block *cifs_get_tcp_super(struct TCP_Server_Info *server) > +{ > + struct super_cb_data d = { > + .server = server, > + .sb = NULL, > + }; > + > + iterate_supers_type(&cifs_fs_type, super_cb, &d); > + > + if (unlikely(!d.sb)) > + return ERR_PTR(-ENOENT); > + /* > + * Grab an active reference in order to prevent automounts (DFS links) > + * of expiring and then freeing up our cifs superblock pointer while > + * we're doing failover. > + */ > + cifs_sb_active(d.sb); > + return d.sb; > +} > + > +void cifs_put_tcp_super(struct super_block *sb) > +{ > + if (!IS_ERR_OR_NULL(sb)) > + cifs_sb_deactive(sb); > +} > + > +int update_super_prepath(struct cifs_tcon *tcon, const char *prefix, > + size_t prefix_len) > +{ > + struct super_block *sb; > + struct cifs_sb_info *cifs_sb; > + int rc = 0; > + > + sb = cifs_get_tcp_super(tcon->ses->server); > + if (IS_ERR(sb)) > + return PTR_ERR(sb); > + > + cifs_sb = CIFS_SB(sb); > + > + kfree(cifs_sb->prepath); > + > + if (*prefix && prefix_len) { > + cifs_sb->prepath = kstrndup(prefix, prefix_len, GFP_ATOMIC); > + if (!cifs_sb->prepath) { > + rc = -ENOMEM; > + goto out; > + } > + > + convert_delimiter(cifs_sb->prepath, CIFS_DIR_SEP(cifs_sb)); > + } else > + cifs_sb->prepath = NULL; > + > + cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH; > + > +out: > + cifs_put_tcp_super(sb); > + return rc; > +} > diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c > index abc0a0512181..49b15a488ede 100644 > --- a/fs/cifs/smb2pdu.c > +++ b/fs/cifs/smb2pdu.c > @@ -193,9 +193,18 @@ static int __smb2_reconnect(const struct nls_table *nlsc, > > for (it = dfs_cache_get_tgt_iterator(&tl); it; > it = dfs_cache_get_next_tgt(&tl, it)) { > - const char *tgt = dfs_cache_get_tgt_name(it); > + const char *share, *prefix; > + size_t share_len, prefix_len; > > - extract_unc_hostname(tgt, &dfs_host, &dfs_host_len); > + rc = dfs_cache_get_tgt_share(it, &share, &share_len, &prefix, > + &prefix_len); > + if (rc) { > + cifs_dbg(VFS, "%s: failed to parse target share %d\n", > + __func__, rc); > + continue; > + } > + > + extract_unc_hostname(share, &dfs_host, &dfs_host_len); > > if (dfs_host_len != tcp_host_len > || strncasecmp(dfs_host, tcp_host, dfs_host_len) != 0) { > @@ -206,11 +215,13 @@ static int __smb2_reconnect(const struct nls_table *nlsc, > continue; > } > > - scnprintf(tree, MAX_TREE_SIZE, "\\%s", tgt); > + scnprintf(tree, MAX_TREE_SIZE, "\\%.*s", (int)share_len, share); > > rc = SMB2_tcon(0, tcon->ses, tree, tcon, nlsc); > - if (!rc) > + if (!rc) { > + rc = update_super_prepath(tcon, prefix, prefix_len); > break; > + } > if (rc == -EREMOTE) > break; > } > -- > 2.25.0 >
merged both into cifs-2.6.git for-next (the 2nd one earlier, so it could be sent to a 5.6-rc ie before 5.7) On Thu, Feb 20, 2020 at 6:08 PM ronnie sahlberg <ronniesahlberg@gmail.com> wrote: > > Acked-by: Ronnie Sahlberg <lsahlber@redhat.com> > > On Fri, Feb 21, 2020 at 8:50 AM Paulo Alcantara (SUSE) <pc@cjr.nz> wrote: > > > > For the case where we have a DFS path like below and we're currently > > connected to targetA: > > > > //dfsroot/link -> //targetA/share/foo, //targetB/share/bar > > > > after failover, we should make sure to update cifs_sb->prepath so the > > next operations will use the new prefix path "/bar". > > > > Besides, in order to simplify the use of different prefix paths, > > enforce CIFS_MOUNT_USE_PREFIX_PATH for DFS mounts so we don't have to > > revalidate the root dentry every time we set a new prefix path. > > > > Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz> > > --- > > fs/cifs/cifsproto.h | 5 +++ > > fs/cifs/cifssmb.c | 19 ++++++++--- > > fs/cifs/connect.c | 63 +++++++---------------------------- > > fs/cifs/dfs_cache.c | 38 +++++++++++++++++++++ > > fs/cifs/dfs_cache.h | 4 +++ > > fs/cifs/misc.c | 80 +++++++++++++++++++++++++++++++++++++++++++++ > > fs/cifs/smb2pdu.c | 19 ++++++++--- > > 7 files changed, 169 insertions(+), 59 deletions(-) > > > > diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h > > index 89eaaf46d1ca..af8e79b58b94 100644 > > --- a/fs/cifs/cifsproto.h > > +++ b/fs/cifs/cifsproto.h > > @@ -601,6 +601,11 @@ int smb2_parse_query_directory(struct cifs_tcon *tcon, struct kvec *rsp_iov, > > int resp_buftype, > > struct cifs_search_info *srch_inf); > > > > +struct super_block *cifs_get_tcp_super(struct TCP_Server_Info *server); > > +void cifs_put_tcp_super(struct super_block *sb); > > +int update_super_prepath(struct cifs_tcon *tcon, const char *prefix, > > + size_t prefix_len); > > + > > #ifdef CONFIG_CIFS_DFS_UPCALL > > static inline int get_dfs_path(const unsigned int xid, struct cifs_ses *ses, > > const char *old_path, > > diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c > > index 3c89569e7210..b6fa575d2d3f 100644 > > --- a/fs/cifs/cifssmb.c > > +++ b/fs/cifs/cifssmb.c > > @@ -162,9 +162,18 @@ static int __cifs_reconnect_tcon(const struct nls_table *nlsc, > > > > for (it = dfs_cache_get_tgt_iterator(&tl); it; > > it = dfs_cache_get_next_tgt(&tl, it)) { > > - const char *tgt = dfs_cache_get_tgt_name(it); > > + const char *share, *prefix; > > + size_t share_len, prefix_len; > > > > - extract_unc_hostname(tgt, &dfs_host, &dfs_host_len); > > + rc = dfs_cache_get_tgt_share(it, &share, &share_len, &prefix, > > + &prefix_len); > > + if (rc) { > > + cifs_dbg(VFS, "%s: failed to parse target share %d\n", > > + __func__, rc); > > + continue; > > + } > > + > > + extract_unc_hostname(share, &dfs_host, &dfs_host_len); > > > > if (dfs_host_len != tcp_host_len > > || strncasecmp(dfs_host, tcp_host, dfs_host_len) != 0) { > > @@ -175,11 +184,13 @@ static int __cifs_reconnect_tcon(const struct nls_table *nlsc, > > continue; > > } > > > > - scnprintf(tree, MAX_TREE_SIZE, "\\%s", tgt); > > + scnprintf(tree, MAX_TREE_SIZE, "\\%.*s", (int)share_len, share); > > > > rc = CIFSTCon(0, tcon->ses, tree, tcon, nlsc); > > - if (!rc) > > + if (!rc) { > > + rc = update_super_prepath(tcon, prefix, prefix_len); > > break; > > + } > > if (rc == -EREMOTE) > > break; > > } > > diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c > > index 4804d1df8c1c..e2196b363765 100644 > > --- a/fs/cifs/connect.c > > +++ b/fs/cifs/connect.c > > @@ -57,7 +57,6 @@ > > #include "smb2proto.h" > > #include "smbdirect.h" > > #include "dns_resolve.h" > > -#include "cifsfs.h" > > #ifdef CONFIG_CIFS_DFS_UPCALL > > #include "dfs_cache.h" > > #endif > > @@ -389,54 +388,7 @@ static inline int reconn_set_ipaddr(struct TCP_Server_Info *server) > > #endif > > > > #ifdef CONFIG_CIFS_DFS_UPCALL > > -struct super_cb_data { > > - struct TCP_Server_Info *server; > > - struct super_block *sb; > > -}; > > - > > /* These functions must be called with server->srv_mutex held */ > > - > > -static void super_cb(struct super_block *sb, void *arg) > > -{ > > - struct super_cb_data *d = arg; > > - struct cifs_sb_info *cifs_sb; > > - struct cifs_tcon *tcon; > > - > > - if (d->sb) > > - return; > > - > > - cifs_sb = CIFS_SB(sb); > > - tcon = cifs_sb_master_tcon(cifs_sb); > > - if (tcon->ses->server == d->server) > > - d->sb = sb; > > -} > > - > > -static struct super_block *get_tcp_super(struct TCP_Server_Info *server) > > -{ > > - struct super_cb_data d = { > > - .server = server, > > - .sb = NULL, > > - }; > > - > > - iterate_supers_type(&cifs_fs_type, super_cb, &d); > > - > > - if (unlikely(!d.sb)) > > - return ERR_PTR(-ENOENT); > > - /* > > - * Grab an active reference in order to prevent automounts (DFS links) > > - * of expiring and then freeing up our cifs superblock pointer while > > - * we're doing failover. > > - */ > > - cifs_sb_active(d.sb); > > - return d.sb; > > -} > > - > > -static inline void put_tcp_super(struct super_block *sb) > > -{ > > - if (!IS_ERR_OR_NULL(sb)) > > - cifs_sb_deactive(sb); > > -} > > - > > static void reconn_inval_dfs_target(struct TCP_Server_Info *server, > > struct cifs_sb_info *cifs_sb, > > struct dfs_cache_tgt_list *tgt_list, > > @@ -508,7 +460,7 @@ cifs_reconnect(struct TCP_Server_Info *server) > > server->nr_targets = 1; > > #ifdef CONFIG_CIFS_DFS_UPCALL > > spin_unlock(&GlobalMid_Lock); > > - sb = get_tcp_super(server); > > + sb = cifs_get_tcp_super(server); > > if (IS_ERR(sb)) { > > rc = PTR_ERR(sb); > > cifs_dbg(FYI, "%s: will not do DFS failover: rc = %d\n", > > @@ -535,7 +487,7 @@ cifs_reconnect(struct TCP_Server_Info *server) > > spin_unlock(&GlobalMid_Lock); > > #ifdef CONFIG_CIFS_DFS_UPCALL > > dfs_cache_free_tgts(&tgt_list); > > - put_tcp_super(sb); > > + cifs_put_tcp_super(sb); > > #endif > > return rc; > > } else > > @@ -666,7 +618,7 @@ cifs_reconnect(struct TCP_Server_Info *server) > > > > } > > > > - put_tcp_super(sb); > > + cifs_put_tcp_super(sb); > > #endif > > if (server->tcpStatus == CifsNeedNegotiate) > > mod_delayed_work(cifsiod_wq, &server->echo, 0); > > @@ -4999,6 +4951,15 @@ int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb_vol *vol) > > * dentry revalidation to think the dentry are stale (ESTALE). > > */ > > cifs_autodisable_serverino(cifs_sb); > > + /* > > + * Force the use of prefix path to support failover on DFS paths that > > + * resolve to targets that have different prefix paths. > > + */ > > + cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH; > > + kfree(cifs_sb->prepath); > > + cifs_sb->prepath = vol->prepath; > > + vol->prepath = NULL; > > + > > out: > > free_xid(xid); > > cifs_try_adding_channels(ses); > > diff --git a/fs/cifs/dfs_cache.c b/fs/cifs/dfs_cache.c > > index 43c1b43a07ec..a67f88bf7ae1 100644 > > --- a/fs/cifs/dfs_cache.c > > +++ b/fs/cifs/dfs_cache.c > > @@ -1260,6 +1260,44 @@ void dfs_cache_del_vol(const char *fullpath) > > kref_put(&vi->refcnt, vol_release); > > } > > > > +/** > > + * dfs_cache_get_tgt_share - parse a DFS target > > + * > > + * @it: DFS target iterator. > > + * @share: tree name. > > + * @share_len: length of tree name. > > + * @prefix: prefix path. > > + * @prefix_len: length of prefix path. > > + * > > + * Return zero if target was parsed correctly, otherwise non-zero. > > + */ > > +int dfs_cache_get_tgt_share(const struct dfs_cache_tgt_iterator *it, > > + const char **share, size_t *share_len, > > + const char **prefix, size_t *prefix_len) > > +{ > > + char *s, sep; > > + > > + if (!it || !share || !share_len || !prefix || !prefix_len) > > + return -EINVAL; > > + > > + sep = it->it_name[0]; > > + if (sep != '\\' && sep != '/') > > + return -EINVAL; > > + > > + s = strchr(it->it_name + 1, sep); > > + if (!s) > > + return -EINVAL; > > + > > + s = strchrnul(s + 1, sep); > > + > > + *share = it->it_name; > > + *share_len = s - it->it_name; > > + *prefix = *s ? s + 1 : s; > > + *prefix_len = &it->it_name[strlen(it->it_name)] - *prefix; > > + > > + return 0; > > +} > > + > > /* Get all tcons that are within a DFS namespace and can be refreshed */ > > static void get_tcons(struct TCP_Server_Info *server, struct list_head *head) > > { > > diff --git a/fs/cifs/dfs_cache.h b/fs/cifs/dfs_cache.h > > index 99ee44f8ad07..bf94d08cfb5a 100644 > > --- a/fs/cifs/dfs_cache.h > > +++ b/fs/cifs/dfs_cache.h > > @@ -49,6 +49,10 @@ extern int dfs_cache_update_vol(const char *fullpath, > > struct TCP_Server_Info *server); > > extern void dfs_cache_del_vol(const char *fullpath); > > > > +extern int dfs_cache_get_tgt_share(const struct dfs_cache_tgt_iterator *it, > > + const char **share, size_t *share_len, > > + const char **prefix, size_t *prefix_len); > > + > > static inline struct dfs_cache_tgt_iterator * > > dfs_cache_get_next_tgt(struct dfs_cache_tgt_list *tl, > > struct dfs_cache_tgt_iterator *it) > > diff --git a/fs/cifs/misc.c b/fs/cifs/misc.c > > index 40ca394fd5de..a456febd4109 100644 > > --- a/fs/cifs/misc.c > > +++ b/fs/cifs/misc.c > > @@ -31,6 +31,7 @@ > > #include "nterr.h" > > #include "cifs_unicode.h" > > #include "smb2pdu.h" > > +#include "cifsfs.h" > > > > extern mempool_t *cifs_sm_req_poolp; > > extern mempool_t *cifs_req_poolp; > > @@ -1022,3 +1023,82 @@ int copy_path_name(char *dst, const char *src) > > name_len++; > > return name_len; > > } > > + > > +struct super_cb_data { > > + struct TCP_Server_Info *server; > > + struct super_block *sb; > > +}; > > + > > +static void super_cb(struct super_block *sb, void *arg) > > +{ > > + struct super_cb_data *d = arg; > > + struct cifs_sb_info *cifs_sb; > > + struct cifs_tcon *tcon; > > + > > + if (d->sb) > > + return; > > + > > + cifs_sb = CIFS_SB(sb); > > + tcon = cifs_sb_master_tcon(cifs_sb); > > + if (tcon->ses->server == d->server) > > + d->sb = sb; > > +} > > + > > +struct super_block *cifs_get_tcp_super(struct TCP_Server_Info *server) > > +{ > > + struct super_cb_data d = { > > + .server = server, > > + .sb = NULL, > > + }; > > + > > + iterate_supers_type(&cifs_fs_type, super_cb, &d); > > + > > + if (unlikely(!d.sb)) > > + return ERR_PTR(-ENOENT); > > + /* > > + * Grab an active reference in order to prevent automounts (DFS links) > > + * of expiring and then freeing up our cifs superblock pointer while > > + * we're doing failover. > > + */ > > + cifs_sb_active(d.sb); > > + return d.sb; > > +} > > + > > +void cifs_put_tcp_super(struct super_block *sb) > > +{ > > + if (!IS_ERR_OR_NULL(sb)) > > + cifs_sb_deactive(sb); > > +} > > + > > +int update_super_prepath(struct cifs_tcon *tcon, const char *prefix, > > + size_t prefix_len) > > +{ > > + struct super_block *sb; > > + struct cifs_sb_info *cifs_sb; > > + int rc = 0; > > + > > + sb = cifs_get_tcp_super(tcon->ses->server); > > + if (IS_ERR(sb)) > > + return PTR_ERR(sb); > > + > > + cifs_sb = CIFS_SB(sb); > > + > > + kfree(cifs_sb->prepath); > > + > > + if (*prefix && prefix_len) { > > + cifs_sb->prepath = kstrndup(prefix, prefix_len, GFP_ATOMIC); > > + if (!cifs_sb->prepath) { > > + rc = -ENOMEM; > > + goto out; > > + } > > + > > + convert_delimiter(cifs_sb->prepath, CIFS_DIR_SEP(cifs_sb)); > > + } else > > + cifs_sb->prepath = NULL; > > + > > + cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH; > > + > > +out: > > + cifs_put_tcp_super(sb); > > + return rc; > > +} > > diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c > > index abc0a0512181..49b15a488ede 100644 > > --- a/fs/cifs/smb2pdu.c > > +++ b/fs/cifs/smb2pdu.c > > @@ -193,9 +193,18 @@ static int __smb2_reconnect(const struct nls_table *nlsc, > > > > for (it = dfs_cache_get_tgt_iterator(&tl); it; > > it = dfs_cache_get_next_tgt(&tl, it)) { > > - const char *tgt = dfs_cache_get_tgt_name(it); > > + const char *share, *prefix; > > + size_t share_len, prefix_len; > > > > - extract_unc_hostname(tgt, &dfs_host, &dfs_host_len); > > + rc = dfs_cache_get_tgt_share(it, &share, &share_len, &prefix, > > + &prefix_len); > > + if (rc) { > > + cifs_dbg(VFS, "%s: failed to parse target share %d\n", > > + __func__, rc); > > + continue; > > + } > > + > > + extract_unc_hostname(share, &dfs_host, &dfs_host_len); > > > > if (dfs_host_len != tcp_host_len > > || strncasecmp(dfs_host, tcp_host, dfs_host_len) != 0) { > > @@ -206,11 +215,13 @@ static int __smb2_reconnect(const struct nls_table *nlsc, > > continue; > > } > > > > - scnprintf(tree, MAX_TREE_SIZE, "\\%s", tgt); > > + scnprintf(tree, MAX_TREE_SIZE, "\\%.*s", (int)share_len, share); > > > > rc = SMB2_tcon(0, tcon->ses, tree, tcon, nlsc); > > - if (!rc) > > + if (!rc) { > > + rc = update_super_prepath(tcon, prefix, prefix_len); > > break; > > + } > > if (rc == -EREMOTE) > > break; > > } > > -- > > 2.25.0 > >
And kicked off DFS automated tests in buildbot (after updating github tree as well) http://smb3-test-rhel-75.southcentralus.cloudapp.azure.com/#/builders/3/builds/69 On Thu, Feb 20, 2020 at 6:30 PM Steve French <smfrench@gmail.com> wrote: > > merged both into cifs-2.6.git for-next (the 2nd one earlier, so it > could be sent to a 5.6-rc ie before 5.7) > > On Thu, Feb 20, 2020 at 6:08 PM ronnie sahlberg > <ronniesahlberg@gmail.com> wrote: > > > > Acked-by: Ronnie Sahlberg <lsahlber@redhat.com> > > > > On Fri, Feb 21, 2020 at 8:50 AM Paulo Alcantara (SUSE) <pc@cjr.nz> wrote: > > > > > > For the case where we have a DFS path like below and we're currently > > > connected to targetA: > > > > > > //dfsroot/link -> //targetA/share/foo, //targetB/share/bar > > > > > > after failover, we should make sure to update cifs_sb->prepath so the > > > next operations will use the new prefix path "/bar". > > > > > > Besides, in order to simplify the use of different prefix paths, > > > enforce CIFS_MOUNT_USE_PREFIX_PATH for DFS mounts so we don't have to > > > revalidate the root dentry every time we set a new prefix path. > > > > > > Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz> > > > --- > > > fs/cifs/cifsproto.h | 5 +++ > > > fs/cifs/cifssmb.c | 19 ++++++++--- > > > fs/cifs/connect.c | 63 +++++++---------------------------- > > > fs/cifs/dfs_cache.c | 38 +++++++++++++++++++++ > > > fs/cifs/dfs_cache.h | 4 +++ > > > fs/cifs/misc.c | 80 +++++++++++++++++++++++++++++++++++++++++++++ > > > fs/cifs/smb2pdu.c | 19 ++++++++--- > > > 7 files changed, 169 insertions(+), 59 deletions(-) > > > > > > diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h > > > index 89eaaf46d1ca..af8e79b58b94 100644 > > > --- a/fs/cifs/cifsproto.h > > > +++ b/fs/cifs/cifsproto.h > > > @@ -601,6 +601,11 @@ int smb2_parse_query_directory(struct cifs_tcon *tcon, struct kvec *rsp_iov, > > > int resp_buftype, > > > struct cifs_search_info *srch_inf); > > > > > > +struct super_block *cifs_get_tcp_super(struct TCP_Server_Info *server); > > > +void cifs_put_tcp_super(struct super_block *sb); > > > +int update_super_prepath(struct cifs_tcon *tcon, const char *prefix, > > > + size_t prefix_len); > > > + > > > #ifdef CONFIG_CIFS_DFS_UPCALL > > > static inline int get_dfs_path(const unsigned int xid, struct cifs_ses *ses, > > > const char *old_path, > > > diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c > > > index 3c89569e7210..b6fa575d2d3f 100644 > > > --- a/fs/cifs/cifssmb.c > > > +++ b/fs/cifs/cifssmb.c > > > @@ -162,9 +162,18 @@ static int __cifs_reconnect_tcon(const struct nls_table *nlsc, > > > > > > for (it = dfs_cache_get_tgt_iterator(&tl); it; > > > it = dfs_cache_get_next_tgt(&tl, it)) { > > > - const char *tgt = dfs_cache_get_tgt_name(it); > > > + const char *share, *prefix; > > > + size_t share_len, prefix_len; > > > > > > - extract_unc_hostname(tgt, &dfs_host, &dfs_host_len); > > > + rc = dfs_cache_get_tgt_share(it, &share, &share_len, &prefix, > > > + &prefix_len); > > > + if (rc) { > > > + cifs_dbg(VFS, "%s: failed to parse target share %d\n", > > > + __func__, rc); > > > + continue; > > > + } > > > + > > > + extract_unc_hostname(share, &dfs_host, &dfs_host_len); > > > > > > if (dfs_host_len != tcp_host_len > > > || strncasecmp(dfs_host, tcp_host, dfs_host_len) != 0) { > > > @@ -175,11 +184,13 @@ static int __cifs_reconnect_tcon(const struct nls_table *nlsc, > > > continue; > > > } > > > > > > - scnprintf(tree, MAX_TREE_SIZE, "\\%s", tgt); > > > + scnprintf(tree, MAX_TREE_SIZE, "\\%.*s", (int)share_len, share); > > > > > > rc = CIFSTCon(0, tcon->ses, tree, tcon, nlsc); > > > - if (!rc) > > > + if (!rc) { > > > + rc = update_super_prepath(tcon, prefix, prefix_len); > > > break; > > > + } > > > if (rc == -EREMOTE) > > > break; > > > } > > > diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c > > > index 4804d1df8c1c..e2196b363765 100644 > > > --- a/fs/cifs/connect.c > > > +++ b/fs/cifs/connect.c > > > @@ -57,7 +57,6 @@ > > > #include "smb2proto.h" > > > #include "smbdirect.h" > > > #include "dns_resolve.h" > > > -#include "cifsfs.h" > > > #ifdef CONFIG_CIFS_DFS_UPCALL > > > #include "dfs_cache.h" > > > #endif > > > @@ -389,54 +388,7 @@ static inline int reconn_set_ipaddr(struct TCP_Server_Info *server) > > > #endif > > > > > > #ifdef CONFIG_CIFS_DFS_UPCALL > > > -struct super_cb_data { > > > - struct TCP_Server_Info *server; > > > - struct super_block *sb; > > > -}; > > > - > > > /* These functions must be called with server->srv_mutex held */ > > > - > > > -static void super_cb(struct super_block *sb, void *arg) > > > -{ > > > - struct super_cb_data *d = arg; > > > - struct cifs_sb_info *cifs_sb; > > > - struct cifs_tcon *tcon; > > > - > > > - if (d->sb) > > > - return; > > > - > > > - cifs_sb = CIFS_SB(sb); > > > - tcon = cifs_sb_master_tcon(cifs_sb); > > > - if (tcon->ses->server == d->server) > > > - d->sb = sb; > > > -} > > > - > > > -static struct super_block *get_tcp_super(struct TCP_Server_Info *server) > > > -{ > > > - struct super_cb_data d = { > > > - .server = server, > > > - .sb = NULL, > > > - }; > > > - > > > - iterate_supers_type(&cifs_fs_type, super_cb, &d); > > > - > > > - if (unlikely(!d.sb)) > > > - return ERR_PTR(-ENOENT); > > > - /* > > > - * Grab an active reference in order to prevent automounts (DFS links) > > > - * of expiring and then freeing up our cifs superblock pointer while > > > - * we're doing failover. > > > - */ > > > - cifs_sb_active(d.sb); > > > - return d.sb; > > > -} > > > - > > > -static inline void put_tcp_super(struct super_block *sb) > > > -{ > > > - if (!IS_ERR_OR_NULL(sb)) > > > - cifs_sb_deactive(sb); > > > -} > > > - > > > static void reconn_inval_dfs_target(struct TCP_Server_Info *server, > > > struct cifs_sb_info *cifs_sb, > > > struct dfs_cache_tgt_list *tgt_list, > > > @@ -508,7 +460,7 @@ cifs_reconnect(struct TCP_Server_Info *server) > > > server->nr_targets = 1; > > > #ifdef CONFIG_CIFS_DFS_UPCALL > > > spin_unlock(&GlobalMid_Lock); > > > - sb = get_tcp_super(server); > > > + sb = cifs_get_tcp_super(server); > > > if (IS_ERR(sb)) { > > > rc = PTR_ERR(sb); > > > cifs_dbg(FYI, "%s: will not do DFS failover: rc = %d\n", > > > @@ -535,7 +487,7 @@ cifs_reconnect(struct TCP_Server_Info *server) > > > spin_unlock(&GlobalMid_Lock); > > > #ifdef CONFIG_CIFS_DFS_UPCALL > > > dfs_cache_free_tgts(&tgt_list); > > > - put_tcp_super(sb); > > > + cifs_put_tcp_super(sb); > > > #endif > > > return rc; > > > } else > > > @@ -666,7 +618,7 @@ cifs_reconnect(struct TCP_Server_Info *server) > > > > > > } > > > > > > - put_tcp_super(sb); > > > + cifs_put_tcp_super(sb); > > > #endif > > > if (server->tcpStatus == CifsNeedNegotiate) > > > mod_delayed_work(cifsiod_wq, &server->echo, 0); > > > @@ -4999,6 +4951,15 @@ int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb_vol *vol) > > > * dentry revalidation to think the dentry are stale (ESTALE). > > > */ > > > cifs_autodisable_serverino(cifs_sb); > > > + /* > > > + * Force the use of prefix path to support failover on DFS paths that > > > + * resolve to targets that have different prefix paths. > > > + */ > > > + cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH; > > > + kfree(cifs_sb->prepath); > > > + cifs_sb->prepath = vol->prepath; > > > + vol->prepath = NULL; > > > + > > > out: > > > free_xid(xid); > > > cifs_try_adding_channels(ses); > > > diff --git a/fs/cifs/dfs_cache.c b/fs/cifs/dfs_cache.c > > > index 43c1b43a07ec..a67f88bf7ae1 100644 > > > --- a/fs/cifs/dfs_cache.c > > > +++ b/fs/cifs/dfs_cache.c > > > @@ -1260,6 +1260,44 @@ void dfs_cache_del_vol(const char *fullpath) > > > kref_put(&vi->refcnt, vol_release); > > > } > > > > > > +/** > > > + * dfs_cache_get_tgt_share - parse a DFS target > > > + * > > > + * @it: DFS target iterator. > > > + * @share: tree name. > > > + * @share_len: length of tree name. > > > + * @prefix: prefix path. > > > + * @prefix_len: length of prefix path. > > > + * > > > + * Return zero if target was parsed correctly, otherwise non-zero. > > > + */ > > > +int dfs_cache_get_tgt_share(const struct dfs_cache_tgt_iterator *it, > > > + const char **share, size_t *share_len, > > > + const char **prefix, size_t *prefix_len) > > > +{ > > > + char *s, sep; > > > + > > > + if (!it || !share || !share_len || !prefix || !prefix_len) > > > + return -EINVAL; > > > + > > > + sep = it->it_name[0]; > > > + if (sep != '\\' && sep != '/') > > > + return -EINVAL; > > > + > > > + s = strchr(it->it_name + 1, sep); > > > + if (!s) > > > + return -EINVAL; > > > + > > > + s = strchrnul(s + 1, sep); > > > + > > > + *share = it->it_name; > > > + *share_len = s - it->it_name; > > > + *prefix = *s ? s + 1 : s; > > > + *prefix_len = &it->it_name[strlen(it->it_name)] - *prefix; > > > + > > > + return 0; > > > +} > > > + > > > /* Get all tcons that are within a DFS namespace and can be refreshed */ > > > static void get_tcons(struct TCP_Server_Info *server, struct list_head *head) > > > { > > > diff --git a/fs/cifs/dfs_cache.h b/fs/cifs/dfs_cache.h > > > index 99ee44f8ad07..bf94d08cfb5a 100644 > > > --- a/fs/cifs/dfs_cache.h > > > +++ b/fs/cifs/dfs_cache.h > > > @@ -49,6 +49,10 @@ extern int dfs_cache_update_vol(const char *fullpath, > > > struct TCP_Server_Info *server); > > > extern void dfs_cache_del_vol(const char *fullpath); > > > > > > +extern int dfs_cache_get_tgt_share(const struct dfs_cache_tgt_iterator *it, > > > + const char **share, size_t *share_len, > > > + const char **prefix, size_t *prefix_len); > > > + > > > static inline struct dfs_cache_tgt_iterator * > > > dfs_cache_get_next_tgt(struct dfs_cache_tgt_list *tl, > > > struct dfs_cache_tgt_iterator *it) > > > diff --git a/fs/cifs/misc.c b/fs/cifs/misc.c > > > index 40ca394fd5de..a456febd4109 100644 > > > --- a/fs/cifs/misc.c > > > +++ b/fs/cifs/misc.c > > > @@ -31,6 +31,7 @@ > > > #include "nterr.h" > > > #include "cifs_unicode.h" > > > #include "smb2pdu.h" > > > +#include "cifsfs.h" > > > > > > extern mempool_t *cifs_sm_req_poolp; > > > extern mempool_t *cifs_req_poolp; > > > @@ -1022,3 +1023,82 @@ int copy_path_name(char *dst, const char *src) > > > name_len++; > > > return name_len; > > > } > > > + > > > +struct super_cb_data { > > > + struct TCP_Server_Info *server; > > > + struct super_block *sb; > > > +}; > > > + > > > +static void super_cb(struct super_block *sb, void *arg) > > > +{ > > > + struct super_cb_data *d = arg; > > > + struct cifs_sb_info *cifs_sb; > > > + struct cifs_tcon *tcon; > > > + > > > + if (d->sb) > > > + return; > > > + > > > + cifs_sb = CIFS_SB(sb); > > > + tcon = cifs_sb_master_tcon(cifs_sb); > > > + if (tcon->ses->server == d->server) > > > + d->sb = sb; > > > +} > > > + > > > +struct super_block *cifs_get_tcp_super(struct TCP_Server_Info *server) > > > +{ > > > + struct super_cb_data d = { > > > + .server = server, > > > + .sb = NULL, > > > + }; > > > + > > > + iterate_supers_type(&cifs_fs_type, super_cb, &d); > > > + > > > + if (unlikely(!d.sb)) > > > + return ERR_PTR(-ENOENT); > > > + /* > > > + * Grab an active reference in order to prevent automounts (DFS links) > > > + * of expiring and then freeing up our cifs superblock pointer while > > > + * we're doing failover. > > > + */ > > > + cifs_sb_active(d.sb); > > > + return d.sb; > > > +} > > > + > > > +void cifs_put_tcp_super(struct super_block *sb) > > > +{ > > > + if (!IS_ERR_OR_NULL(sb)) > > > + cifs_sb_deactive(sb); > > > +} > > > + > > > +int update_super_prepath(struct cifs_tcon *tcon, const char *prefix, > > > + size_t prefix_len) > > > +{ > > > + struct super_block *sb; > > > + struct cifs_sb_info *cifs_sb; > > > + int rc = 0; > > > + > > > + sb = cifs_get_tcp_super(tcon->ses->server); > > > + if (IS_ERR(sb)) > > > + return PTR_ERR(sb); > > > + > > > + cifs_sb = CIFS_SB(sb); > > > + > > > + kfree(cifs_sb->prepath); > > > + > > > + if (*prefix && prefix_len) { > > > + cifs_sb->prepath = kstrndup(prefix, prefix_len, GFP_ATOMIC); > > > + if (!cifs_sb->prepath) { > > > + rc = -ENOMEM; > > > + goto out; > > > + } > > > + > > > + convert_delimiter(cifs_sb->prepath, CIFS_DIR_SEP(cifs_sb)); > > > + } else > > > + cifs_sb->prepath = NULL; > > > + > > > + cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH; > > > + > > > +out: > > > + cifs_put_tcp_super(sb); > > > + return rc; > > > +} > > > diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c > > > index abc0a0512181..49b15a488ede 100644 > > > --- a/fs/cifs/smb2pdu.c > > > +++ b/fs/cifs/smb2pdu.c > > > @@ -193,9 +193,18 @@ static int __smb2_reconnect(const struct nls_table *nlsc, > > > > > > for (it = dfs_cache_get_tgt_iterator(&tl); it; > > > it = dfs_cache_get_next_tgt(&tl, it)) { > > > - const char *tgt = dfs_cache_get_tgt_name(it); > > > + const char *share, *prefix; > > > + size_t share_len, prefix_len; > > > > > > - extract_unc_hostname(tgt, &dfs_host, &dfs_host_len); > > > + rc = dfs_cache_get_tgt_share(it, &share, &share_len, &prefix, > > > + &prefix_len); > > > + if (rc) { > > > + cifs_dbg(VFS, "%s: failed to parse target share %d\n", > > > + __func__, rc); > > > + continue; > > > + } > > > + > > > + extract_unc_hostname(share, &dfs_host, &dfs_host_len); > > > > > > if (dfs_host_len != tcp_host_len > > > || strncasecmp(dfs_host, tcp_host, dfs_host_len) != 0) { > > > @@ -206,11 +215,13 @@ static int __smb2_reconnect(const struct nls_table *nlsc, > > > continue; > > > } > > > > > > - scnprintf(tree, MAX_TREE_SIZE, "\\%s", tgt); > > > + scnprintf(tree, MAX_TREE_SIZE, "\\%.*s", (int)share_len, share); > > > > > > rc = SMB2_tcon(0, tcon->ses, tree, tcon, nlsc); > > > - if (!rc) > > > + if (!rc) { > > > + rc = update_super_prepath(tcon, prefix, prefix_len); > > > break; > > > + } > > > if (rc == -EREMOTE) > > > break; > > > } > > > -- > > > 2.25.0 > > > > > > > -- > Thanks, > > Steve
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
for both patch
Cheers,
diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h index 89eaaf46d1ca..af8e79b58b94 100644 --- a/fs/cifs/cifsproto.h +++ b/fs/cifs/cifsproto.h @@ -601,6 +601,11 @@ int smb2_parse_query_directory(struct cifs_tcon *tcon, struct kvec *rsp_iov, int resp_buftype, struct cifs_search_info *srch_inf); +struct super_block *cifs_get_tcp_super(struct TCP_Server_Info *server); +void cifs_put_tcp_super(struct super_block *sb); +int update_super_prepath(struct cifs_tcon *tcon, const char *prefix, + size_t prefix_len); + #ifdef CONFIG_CIFS_DFS_UPCALL static inline int get_dfs_path(const unsigned int xid, struct cifs_ses *ses, const char *old_path, diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c index 3c89569e7210..b6fa575d2d3f 100644 --- a/fs/cifs/cifssmb.c +++ b/fs/cifs/cifssmb.c @@ -162,9 +162,18 @@ static int __cifs_reconnect_tcon(const struct nls_table *nlsc, for (it = dfs_cache_get_tgt_iterator(&tl); it; it = dfs_cache_get_next_tgt(&tl, it)) { - const char *tgt = dfs_cache_get_tgt_name(it); + const char *share, *prefix; + size_t share_len, prefix_len; - extract_unc_hostname(tgt, &dfs_host, &dfs_host_len); + rc = dfs_cache_get_tgt_share(it, &share, &share_len, &prefix, + &prefix_len); + if (rc) { + cifs_dbg(VFS, "%s: failed to parse target share %d\n", + __func__, rc); + continue; + } + + extract_unc_hostname(share, &dfs_host, &dfs_host_len); if (dfs_host_len != tcp_host_len || strncasecmp(dfs_host, tcp_host, dfs_host_len) != 0) { @@ -175,11 +184,13 @@ static int __cifs_reconnect_tcon(const struct nls_table *nlsc, continue; } - scnprintf(tree, MAX_TREE_SIZE, "\\%s", tgt); + scnprintf(tree, MAX_TREE_SIZE, "\\%.*s", (int)share_len, share); rc = CIFSTCon(0, tcon->ses, tree, tcon, nlsc); - if (!rc) + if (!rc) { + rc = update_super_prepath(tcon, prefix, prefix_len); break; + } if (rc == -EREMOTE) break; } diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c index 4804d1df8c1c..e2196b363765 100644 --- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -57,7 +57,6 @@ #include "smb2proto.h" #include "smbdirect.h" #include "dns_resolve.h" -#include "cifsfs.h" #ifdef CONFIG_CIFS_DFS_UPCALL #include "dfs_cache.h" #endif @@ -389,54 +388,7 @@ static inline int reconn_set_ipaddr(struct TCP_Server_Info *server) #endif #ifdef CONFIG_CIFS_DFS_UPCALL -struct super_cb_data { - struct TCP_Server_Info *server; - struct super_block *sb; -}; - /* These functions must be called with server->srv_mutex held */ - -static void super_cb(struct super_block *sb, void *arg) -{ - struct super_cb_data *d = arg; - struct cifs_sb_info *cifs_sb; - struct cifs_tcon *tcon; - - if (d->sb) - return; - - cifs_sb = CIFS_SB(sb); - tcon = cifs_sb_master_tcon(cifs_sb); - if (tcon->ses->server == d->server) - d->sb = sb; -} - -static struct super_block *get_tcp_super(struct TCP_Server_Info *server) -{ - struct super_cb_data d = { - .server = server, - .sb = NULL, - }; - - iterate_supers_type(&cifs_fs_type, super_cb, &d); - - if (unlikely(!d.sb)) - return ERR_PTR(-ENOENT); - /* - * Grab an active reference in order to prevent automounts (DFS links) - * of expiring and then freeing up our cifs superblock pointer while - * we're doing failover. - */ - cifs_sb_active(d.sb); - return d.sb; -} - -static inline void put_tcp_super(struct super_block *sb) -{ - if (!IS_ERR_OR_NULL(sb)) - cifs_sb_deactive(sb); -} - static void reconn_inval_dfs_target(struct TCP_Server_Info *server, struct cifs_sb_info *cifs_sb, struct dfs_cache_tgt_list *tgt_list, @@ -508,7 +460,7 @@ cifs_reconnect(struct TCP_Server_Info *server) server->nr_targets = 1; #ifdef CONFIG_CIFS_DFS_UPCALL spin_unlock(&GlobalMid_Lock); - sb = get_tcp_super(server); + sb = cifs_get_tcp_super(server); if (IS_ERR(sb)) { rc = PTR_ERR(sb); cifs_dbg(FYI, "%s: will not do DFS failover: rc = %d\n", @@ -535,7 +487,7 @@ cifs_reconnect(struct TCP_Server_Info *server) spin_unlock(&GlobalMid_Lock); #ifdef CONFIG_CIFS_DFS_UPCALL dfs_cache_free_tgts(&tgt_list); - put_tcp_super(sb); + cifs_put_tcp_super(sb); #endif return rc; } else @@ -666,7 +618,7 @@ cifs_reconnect(struct TCP_Server_Info *server) } - put_tcp_super(sb); + cifs_put_tcp_super(sb); #endif if (server->tcpStatus == CifsNeedNegotiate) mod_delayed_work(cifsiod_wq, &server->echo, 0); @@ -4999,6 +4951,15 @@ int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb_vol *vol) * dentry revalidation to think the dentry are stale (ESTALE). */ cifs_autodisable_serverino(cifs_sb); + /* + * Force the use of prefix path to support failover on DFS paths that + * resolve to targets that have different prefix paths. + */ + cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH; + kfree(cifs_sb->prepath); + cifs_sb->prepath = vol->prepath; + vol->prepath = NULL; + out: free_xid(xid); cifs_try_adding_channels(ses); diff --git a/fs/cifs/dfs_cache.c b/fs/cifs/dfs_cache.c index 43c1b43a07ec..a67f88bf7ae1 100644 --- a/fs/cifs/dfs_cache.c +++ b/fs/cifs/dfs_cache.c @@ -1260,6 +1260,44 @@ void dfs_cache_del_vol(const char *fullpath) kref_put(&vi->refcnt, vol_release); } +/** + * dfs_cache_get_tgt_share - parse a DFS target + * + * @it: DFS target iterator. + * @share: tree name. + * @share_len: length of tree name. + * @prefix: prefix path. + * @prefix_len: length of prefix path. + * + * Return zero if target was parsed correctly, otherwise non-zero. + */ +int dfs_cache_get_tgt_share(const struct dfs_cache_tgt_iterator *it, + const char **share, size_t *share_len, + const char **prefix, size_t *prefix_len) +{ + char *s, sep; + + if (!it || !share || !share_len || !prefix || !prefix_len) + return -EINVAL; + + sep = it->it_name[0]; + if (sep != '\\' && sep != '/') + return -EINVAL; + + s = strchr(it->it_name + 1, sep); + if (!s) + return -EINVAL; + + s = strchrnul(s + 1, sep); + + *share = it->it_name; + *share_len = s - it->it_name; + *prefix = *s ? s + 1 : s; + *prefix_len = &it->it_name[strlen(it->it_name)] - *prefix; + + return 0; +} + /* Get all tcons that are within a DFS namespace and can be refreshed */ static void get_tcons(struct TCP_Server_Info *server, struct list_head *head) { diff --git a/fs/cifs/dfs_cache.h b/fs/cifs/dfs_cache.h index 99ee44f8ad07..bf94d08cfb5a 100644 --- a/fs/cifs/dfs_cache.h +++ b/fs/cifs/dfs_cache.h @@ -49,6 +49,10 @@ extern int dfs_cache_update_vol(const char *fullpath, struct TCP_Server_Info *server); extern void dfs_cache_del_vol(const char *fullpath); +extern int dfs_cache_get_tgt_share(const struct dfs_cache_tgt_iterator *it, + const char **share, size_t *share_len, + const char **prefix, size_t *prefix_len); + static inline struct dfs_cache_tgt_iterator * dfs_cache_get_next_tgt(struct dfs_cache_tgt_list *tl, struct dfs_cache_tgt_iterator *it) diff --git a/fs/cifs/misc.c b/fs/cifs/misc.c index 40ca394fd5de..a456febd4109 100644 --- a/fs/cifs/misc.c +++ b/fs/cifs/misc.c @@ -31,6 +31,7 @@ #include "nterr.h" #include "cifs_unicode.h" #include "smb2pdu.h" +#include "cifsfs.h" extern mempool_t *cifs_sm_req_poolp; extern mempool_t *cifs_req_poolp; @@ -1022,3 +1023,82 @@ int copy_path_name(char *dst, const char *src) name_len++; return name_len; } + +struct super_cb_data { + struct TCP_Server_Info *server; + struct super_block *sb; +}; + +static void super_cb(struct super_block *sb, void *arg) +{ + struct super_cb_data *d = arg; + struct cifs_sb_info *cifs_sb; + struct cifs_tcon *tcon; + + if (d->sb) + return; + + cifs_sb = CIFS_SB(sb); + tcon = cifs_sb_master_tcon(cifs_sb); + if (tcon->ses->server == d->server) + d->sb = sb; +} + +struct super_block *cifs_get_tcp_super(struct TCP_Server_Info *server) +{ + struct super_cb_data d = { + .server = server, + .sb = NULL, + }; + + iterate_supers_type(&cifs_fs_type, super_cb, &d); + + if (unlikely(!d.sb)) + return ERR_PTR(-ENOENT); + /* + * Grab an active reference in order to prevent automounts (DFS links) + * of expiring and then freeing up our cifs superblock pointer while + * we're doing failover. + */ + cifs_sb_active(d.sb); + return d.sb; +} + +void cifs_put_tcp_super(struct super_block *sb) +{ + if (!IS_ERR_OR_NULL(sb)) + cifs_sb_deactive(sb); +} + +int update_super_prepath(struct cifs_tcon *tcon, const char *prefix, + size_t prefix_len) +{ + struct super_block *sb; + struct cifs_sb_info *cifs_sb; + int rc = 0; + + sb = cifs_get_tcp_super(tcon->ses->server); + if (IS_ERR(sb)) + return PTR_ERR(sb); + + cifs_sb = CIFS_SB(sb); + + kfree(cifs_sb->prepath); + + if (*prefix && prefix_len) { + cifs_sb->prepath = kstrndup(prefix, prefix_len, GFP_ATOMIC); + if (!cifs_sb->prepath) { + rc = -ENOMEM; + goto out; + } + + convert_delimiter(cifs_sb->prepath, CIFS_DIR_SEP(cifs_sb)); + } else + cifs_sb->prepath = NULL; + + cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH; + +out: + cifs_put_tcp_super(sb); + return rc; +} diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index abc0a0512181..49b15a488ede 100644 --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -193,9 +193,18 @@ static int __smb2_reconnect(const struct nls_table *nlsc, for (it = dfs_cache_get_tgt_iterator(&tl); it; it = dfs_cache_get_next_tgt(&tl, it)) { - const char *tgt = dfs_cache_get_tgt_name(it); + const char *share, *prefix; + size_t share_len, prefix_len; - extract_unc_hostname(tgt, &dfs_host, &dfs_host_len); + rc = dfs_cache_get_tgt_share(it, &share, &share_len, &prefix, + &prefix_len); + if (rc) { + cifs_dbg(VFS, "%s: failed to parse target share %d\n", + __func__, rc); + continue; + } + + extract_unc_hostname(share, &dfs_host, &dfs_host_len); if (dfs_host_len != tcp_host_len || strncasecmp(dfs_host, tcp_host, dfs_host_len) != 0) { @@ -206,11 +215,13 @@ static int __smb2_reconnect(const struct nls_table *nlsc, continue; } - scnprintf(tree, MAX_TREE_SIZE, "\\%s", tgt); + scnprintf(tree, MAX_TREE_SIZE, "\\%.*s", (int)share_len, share); rc = SMB2_tcon(0, tcon->ses, tree, tcon, nlsc); - if (!rc) + if (!rc) { + rc = update_super_prepath(tcon, prefix, prefix_len); break; + } if (rc == -EREMOTE) break; }
For the case where we have a DFS path like below and we're currently connected to targetA: //dfsroot/link -> //targetA/share/foo, //targetB/share/bar after failover, we should make sure to update cifs_sb->prepath so the next operations will use the new prefix path "/bar". Besides, in order to simplify the use of different prefix paths, enforce CIFS_MOUNT_USE_PREFIX_PATH for DFS mounts so we don't have to revalidate the root dentry every time we set a new prefix path. Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz> --- fs/cifs/cifsproto.h | 5 +++ fs/cifs/cifssmb.c | 19 ++++++++--- fs/cifs/connect.c | 63 +++++++---------------------------- fs/cifs/dfs_cache.c | 38 +++++++++++++++++++++ fs/cifs/dfs_cache.h | 4 +++ fs/cifs/misc.c | 80 +++++++++++++++++++++++++++++++++++++++++++++ fs/cifs/smb2pdu.c | 19 ++++++++--- 7 files changed, 169 insertions(+), 59 deletions(-)