diff options
Diffstat (limited to 'fs/cifs/cifs_dfs_ref.c')
-rw-r--r-- | fs/cifs/cifs_dfs_ref.c | 138 |
1 files changed, 86 insertions, 52 deletions
diff --git a/fs/cifs/cifs_dfs_ref.c b/fs/cifs/cifs_dfs_ref.c index b97c74efd04a..d9b99abe1243 100644 --- a/fs/cifs/cifs_dfs_ref.c +++ b/fs/cifs/cifs_dfs_ref.c @@ -25,6 +25,7 @@ #include "dns_resolve.h" #include "cifs_debug.h" #include "cifs_unicode.h" +#include "dfs_cache.h" static LIST_HEAD(cifs_dfs_automount_list); @@ -126,7 +127,7 @@ cifs_build_devname(char *nodename, const char *prepath) * @sb_mountdata: parent/root DFS mount options (template) * @fullpath: full path in UNC format * @ref: server's referral - * @devname: pointer for saving device name + * @devname: optional pointer for saving device name * * creates mount options for submount based on template options sb_mountdata * and replacing unc,ip,prefixpath options with ones we've got form ref_unc. @@ -140,6 +141,7 @@ char *cifs_compose_mount_options(const char *sb_mountdata, char **devname) { int rc; + char *name; char *mountdata = NULL; const char *prepath = NULL; int md_len; @@ -158,17 +160,17 @@ char *cifs_compose_mount_options(const char *sb_mountdata, prepath++; } - *devname = cifs_build_devname(ref->node_name, prepath); - if (IS_ERR(*devname)) { - rc = PTR_ERR(*devname); - *devname = NULL; + name = cifs_build_devname(ref->node_name, prepath); + if (IS_ERR(name)) { + rc = PTR_ERR(name); + name = NULL; goto compose_mount_options_err; } - rc = dns_resolve_server_name_to_ip(*devname, &srvIP); + rc = dns_resolve_server_name_to_ip(name, &srvIP); if (rc < 0) { cifs_dbg(FYI, "%s: Failed to resolve server part of %s to IP: %d\n", - __func__, *devname, rc); + __func__, name, rc); goto compose_mount_options_err; } @@ -224,6 +226,9 @@ char *cifs_compose_mount_options(const char *sb_mountdata, strcat(mountdata, "ip="); strcat(mountdata, srvIP); + if (devname) + *devname = name; + /*cifs_dbg(FYI, "%s: parent mountdata: %s\n", __func__, sb_mountdata);*/ /*cifs_dbg(FYI, "%s: submount mountdata: %s\n", __func__, mountdata );*/ @@ -234,8 +239,7 @@ compose_mount_options_out: compose_mount_options_err: kfree(mountdata); mountdata = ERR_PTR(rc); - kfree(*devname); - *devname = NULL; + kfree(name); goto compose_mount_options_out; } @@ -251,20 +255,30 @@ static struct vfsmount *cifs_dfs_do_refmount(struct dentry *mntpt, { struct vfsmount *mnt; char *mountdata; - char *devname = NULL; + char *devname; + + /* + * Always pass down the DFS full path to smb3_do_mount() so we + * can use it later for failover. + */ + devname = kstrndup(fullpath, strlen(fullpath), GFP_KERNEL); + if (!devname) + return ERR_PTR(-ENOMEM); + + convert_delimiter(devname, '/'); /* strip first '\' from fullpath */ mountdata = cifs_compose_mount_options(cifs_sb->mountdata, - fullpath + 1, ref, &devname); - - if (IS_ERR(mountdata)) + fullpath + 1, ref, NULL); + if (IS_ERR(mountdata)) { + kfree(devname); return (struct vfsmount *)mountdata; + } mnt = vfs_submount(mntpt, &cifs_fs_type, devname, mountdata); kfree(mountdata); kfree(devname); return mnt; - } static void dump_referral(const struct dfs_info3_param *ref) @@ -282,16 +296,15 @@ static void dump_referral(const struct dfs_info3_param *ref) */ static struct vfsmount *cifs_dfs_do_automount(struct dentry *mntpt) { - struct dfs_info3_param *referrals = NULL; - unsigned int num_referrals = 0; + struct dfs_info3_param referral = {0}; struct cifs_sb_info *cifs_sb; struct cifs_ses *ses; - char *full_path; + struct cifs_tcon *tcon; + char *full_path, *root_path; unsigned int xid; - int i; + int len; int rc; struct vfsmount *mnt; - struct tcon_link *tlink; cifs_dbg(FYI, "in %s\n", __func__); BUG_ON(IS_ROOT(mntpt)); @@ -315,48 +328,69 @@ static struct vfsmount *cifs_dfs_do_automount(struct dentry *mntpt) if (full_path == NULL) goto cdda_exit; - tlink = cifs_sb_tlink(cifs_sb); - if (IS_ERR(tlink)) { - mnt = ERR_CAST(tlink); + cifs_dbg(FYI, "%s: full_path: %s\n", __func__, full_path); + + if (!cifs_sb_master_tlink(cifs_sb)) { + cifs_dbg(FYI, "%s: master tlink is NULL\n", __func__); goto free_full_path; } - ses = tlink_tcon(tlink)->ses; + tcon = cifs_sb_master_tcon(cifs_sb); + if (!tcon) { + cifs_dbg(FYI, "%s: master tcon is NULL\n", __func__); + goto free_full_path; + } + + root_path = kstrdup(tcon->treeName, GFP_KERNEL); + if (!root_path) { + mnt = ERR_PTR(-ENOMEM); + goto free_full_path; + } + cifs_dbg(FYI, "%s: root path: %s\n", __func__, root_path); + + ses = tcon->ses; xid = get_xid(); - rc = get_dfs_path(xid, ses, full_path + 1, cifs_sb->local_nls, - &num_referrals, &referrals, - cifs_remap(cifs_sb)); - free_xid(xid); - cifs_put_tlink(tlink); - - mnt = ERR_PTR(-ENOENT); - for (i = 0; i < num_referrals; i++) { - int len; - dump_referral(referrals + i); - /* connect to a node */ - len = strlen(referrals[i].node_name); - if (len < 2) { - cifs_dbg(VFS, "%s: Net Address path too short: %s\n", - __func__, referrals[i].node_name); - mnt = ERR_PTR(-EINVAL); - break; - } - mnt = cifs_dfs_do_refmount(mntpt, cifs_sb, - full_path, referrals + i); - cifs_dbg(FYI, "%s: cifs_dfs_do_refmount:%s , mnt:%p\n", - __func__, referrals[i].node_name, mnt); - if (!IS_ERR(mnt)) - goto success; + /* + * If DFS root has been expired, then unconditionally fetch it again to + * refresh DFS referral cache. + */ + rc = dfs_cache_find(xid, ses, cifs_sb->local_nls, cifs_remap(cifs_sb), + root_path + 1, NULL, NULL); + if (!rc) { + rc = dfs_cache_find(xid, ses, cifs_sb->local_nls, + cifs_remap(cifs_sb), full_path + 1, + &referral, NULL); } - /* no valid submounts were found; return error from get_dfs_path() by - * preference */ - if (rc != 0) + free_xid(xid); + + if (rc) { mnt = ERR_PTR(rc); + goto free_root_path; + } + + dump_referral(&referral); -success: - free_dfs_info_array(referrals, num_referrals); + len = strlen(referral.node_name); + if (len < 2) { + cifs_dbg(VFS, "%s: Net Address path too short: %s\n", + __func__, referral.node_name); + mnt = ERR_PTR(-EINVAL); + goto free_dfs_ref; + } + /* + * cifs_mount() will retry every available node server in case + * of failures. + */ + mnt = cifs_dfs_do_refmount(mntpt, cifs_sb, full_path, &referral); + cifs_dbg(FYI, "%s: cifs_dfs_do_refmount:%s , mnt:%p\n", __func__, + referral.node_name, mnt); + +free_dfs_ref: + free_dfs_info_param(&referral); +free_root_path: + kfree(root_path); free_full_path: kfree(full_path); cdda_exit: |