cifs: Fix DFS cache refresher for DFS links (5072010c) · Commits · 戴 / test

fs/cifs/cifsproto.h

+9 −0

Original line number	Diff line number	Diff line
		@@ -526,12 +526,21 @@ extern int E_md4hash(const unsigned char passwd, unsigned char p16,
		const struct nls_table *codepage);
		extern int SMBencrypt(unsigned char passwd, const unsigned char c8,
		unsigned char *p24);

		extern int
		cifs_setup_volume_info(struct smb_vol volume_info, char mount_data,
		const char *devname, bool is_smb3);
		extern void
		cifs_cleanup_volume_info_contents(struct smb_vol *volume_info);

		extern struct TCP_Server_Info *
		cifs_find_tcp_session(struct smb_vol *vol);

		extern void cifs_put_smb_ses(struct cifs_ses *ses);

		extern struct cifs_ses *
		cifs_get_smb_ses(struct TCP_Server_Info server, struct smb_vol volume_info);

		void cifs_readdata_release(struct kref *refcount);
		int cifs_async_readv(struct cifs_readdata *rdata);
		int cifs_readv_receive(struct TCP_Server_Info server, struct mid_q_entry mid);

fs/cifs/connect.c

+14 −8

Original line number	Diff line number	Diff line
		@@ -323,8 +323,6 @@ static int ip_connect(struct TCP_Server_Info *server);
		static int generic_ip_connect(struct TCP_Server_Info *server);
		static void tlink_rb_insert(struct rb_root root, struct tcon_link new_tlink);
		static void cifs_prune_tlinks(struct work_struct *work);
		static int cifs_setup_volume_info(struct smb_vol volume_info, char mount_data,
		const char *devname, bool is_smb3);
		static char extract_hostname(const char unc);

		/*
		@@ -2904,8 +2902,7 @@ cifs_find_smb_ses(struct TCP_Server_Info server, struct smb_vol vol)
		return NULL;
		}

		static void
		cifs_put_smb_ses(struct cifs_ses *ses)
		void cifs_put_smb_ses(struct cifs_ses *ses)
		{
		unsigned int rc, xid;
		struct TCP_Server_Info *server = ses->server;
		@@ -3082,7 +3079,7 @@ cifs_set_cifscreds(struct smb_vol *vol __attribute__((unused)),
		* already got a server reference (server refcount +1). See
		* cifs_get_tcon() for refcount explanations.
		*/
		static struct cifs_ses *
		struct cifs_ses *
		cifs_get_smb_ses(struct TCP_Server_Info server, struct smb_vol volume_info)
		{
		int rc = -ENOMEM;
		@@ -4389,7 +4386,7 @@ static int mount_do_dfs_failover(const char *path,
		}
		#endif

		static int
		int
		cifs_setup_volume_info(struct smb_vol volume_info, char mount_data,
		const char *devname, bool is_smb3)
		{
		@@ -4543,7 +4540,7 @@ int cifs_mount(struct cifs_sb_info cifs_sb, struct smb_vol vol)
		struct cifs_tcon *tcon = NULL;
		struct TCP_Server_Info *server;
		char root_path = NULL, full_path = NULL;
		char *old_mountdata;
		char old_mountdata, origin_mountdata = NULL;
		int count;

		rc = mount_get_conns(vol, cifs_sb, &xid, &server, &ses, &tcon);
		@@ -4602,6 +4599,14 @@ int cifs_mount(struct cifs_sb_info cifs_sb, struct smb_vol vol)
		goto error;
		}

		/* Save DFS root volume information for DFS refresh worker */
		origin_mountdata = kstrndup(cifs_sb->mountdata,
		strlen(cifs_sb->mountdata), GFP_KERNEL);
		if (!origin_mountdata) {
		rc = -ENOMEM;
		goto error;
		}

		if (cifs_sb->mountdata != old_mountdata) {
		/* If we were redirected, reconnect to new target server */
		mount_put_conns(cifs_sb, xid, server, ses, tcon);
		@@ -4710,7 +4715,7 @@ int cifs_mount(struct cifs_sb_info cifs_sb, struct smb_vol vol)
		}
		spin_unlock(&cifs_tcp_ses_lock);

		rc = dfs_cache_add_vol(vol, cifs_sb->origin_fullpath);
		rc = dfs_cache_add_vol(origin_mountdata, vol, cifs_sb->origin_fullpath);
		if (rc) {
		kfree(cifs_sb->origin_fullpath);
		goto error;
		@@ -4728,6 +4733,7 @@ out:
		error:
		kfree(full_path);
		kfree(root_path);
		kfree(origin_mountdata);
		mount_put_conns(cifs_sb, xid, server, ses, tcon);
		return rc;
		}

fs/cifs/dfs_cache.c

+125 −15

Original line number	Diff line number	Diff line
		@@ -2,7 +2,7 @@
		/*
		* DFS referral cache routines
		*
		* Copyright (c) 2018 Paulo Alcantara <palcantara@suse.de>
		* Copyright (c) 2018-2019 Paulo Alcantara <palcantara@suse.de>
		*/

		#include <linux/rcupdate.h>
		@@ -52,6 +52,7 @@ static struct kmem_cache *dfs_cache_slab __read_mostly;
		struct dfs_cache_vol_info {
		char *vi_fullpath;
		struct smb_vol vi_vol;
		char *vi_mntdata;
		struct list_head vi_list;
		};

		@@ -529,6 +530,7 @@ static inline void free_vol(struct dfs_cache_vol_info *vi)
		{
		list_del(&vi->vi_list);
		kfree(vi->vi_fullpath);
		kfree(vi->vi_mntdata);
		cifs_cleanup_volume_info_contents(&vi->vi_vol);
		kfree(vi);
		}
		@@ -1139,17 +1141,18 @@ err_free_username:
		* dfs_cache_add_vol - add a cifs volume during mount() that will be handled by
		* DFS cache refresh worker.
		*
		* @mntdata: mount data.
		* @vol: cifs volume.
		* @fullpath: origin full path.
		*
		* Return zero if volume was set up correctly, otherwise non-zero.
		*/
		int dfs_cache_add_vol(struct smb_vol vol, const char fullpath)
		int dfs_cache_add_vol(char mntdata, struct smb_vol vol, const char *fullpath)
		{
		int rc;
		struct dfs_cache_vol_info *vi;

		if (!vol \|\| !fullpath)
		if (!vol \|\| !fullpath \|\| !mntdata)
		return -EINVAL;

		cifs_dbg(FYI, "%s: fullpath: %s\n", __func__, fullpath);
		@@ -1168,6 +1171,8 @@ int dfs_cache_add_vol(struct smb_vol vol, const char fullpath)
		if (rc)
		goto err_free_fullpath;

		vi->vi_mntdata = mntdata;

		mutex_lock(&dfs_cache.dc_lock);
		list_add_tail(&vi->vi_list, &dfs_cache.dc_vol_list);
		mutex_unlock(&dfs_cache.dc_lock);
		@@ -1275,8 +1280,102 @@ static void get_tcons(struct TCP_Server_Info server, struct list_head head)
		spin_unlock(&cifs_tcp_ses_lock);
		}

		static inline bool is_dfs_link(const char *path)
		{
		char *s;

		s = strchr(path + 1, '\\');
		if (!s)
		return false;
		return !!strchr(s + 1, '\\');
		}

		static inline char get_dfs_root(const char path)
		{
		char s, npath;

		s = strchr(path + 1, '\\');
		if (!s)
		return ERR_PTR(-EINVAL);

		s = strchr(s + 1, '\\');
		if (!s)
		return ERR_PTR(-EINVAL);

		npath = kstrndup(path, s - path, GFP_KERNEL);
		if (!npath)
		return ERR_PTR(-ENOMEM);

		return npath;
		}

		/* Find root SMB session out of a DFS link path */
		static struct cifs_ses find_root_ses(struct dfs_cache_vol_info vi,
		struct cifs_tcon tcon, const char path)
		{
		char *rpath;
		int rc;
		struct dfs_info3_param ref = {0};
		char mdata = NULL, devname = NULL;
		bool is_smb3 = tcon->ses->server->vals->header_preamble_size == 0;
		struct TCP_Server_Info *server;
		struct cifs_ses *ses;
		struct smb_vol vol;

		rpath = get_dfs_root(path);
		if (IS_ERR(rpath))
		return ERR_CAST(rpath);

		memset(&vol, 0, sizeof(vol));

		rc = dfs_cache_noreq_find(rpath, &ref, NULL);
		if (rc) {
		ses = ERR_PTR(rc);
		goto out;
		}

		mdata = cifs_compose_mount_options(vi->vi_mntdata, rpath, &ref,
		&devname);
		free_dfs_info_param(&ref);

		if (IS_ERR(mdata)) {
		ses = ERR_CAST(mdata);
		mdata = NULL;
		goto out;
		}

		rc = cifs_setup_volume_info(&vol, mdata, devname, is_smb3);
		kfree(devname);

		if (rc) {
		ses = ERR_PTR(rc);
		goto out;
		}

		server = cifs_find_tcp_session(&vol);
		if (IS_ERR_OR_NULL(server)) {
		ses = ERR_PTR(-EHOSTDOWN);
		goto out;
		}
		if (server->tcpStatus != CifsGood) {
		cifs_put_tcp_session(server, 0);
		ses = ERR_PTR(-EHOSTDOWN);
		goto out;
		}

		ses = cifs_get_smb_ses(server, &vol);

		out:
		cifs_cleanup_volume_info_contents(&vol);
		kfree(mdata);
		kfree(rpath);

		return ses;
		}

		/* Refresh DFS cache entry from a given tcon */
		static void do_refresh_tcon(struct dfs_cache dc, struct cifs_tcon tcon)
		static void do_refresh_tcon(struct dfs_cache dc, struct dfs_cache_vol_info vi,
		struct cifs_tcon *tcon)
		{
		int rc = 0;
		unsigned int xid;
		@@ -1285,6 +1384,7 @@ static void do_refresh_tcon(struct dfs_cache dc, struct cifs_tcon tcon)
		struct dfs_cache_entry *ce;
		struct dfs_info3_param *refs = NULL;
		int numrefs = 0;
		struct cifs_ses root_ses = NULL, ses;

		xid = get_xid();

		@@ -1306,12 +1406,23 @@ static void do_refresh_tcon(struct dfs_cache dc, struct cifs_tcon tcon)
		if (!cache_entry_expired(ce))
		goto out;

		if (unlikely(!tcon->ses->server->ops->get_dfs_refer)) {
		/* If it's a DFS Link, then use root SMB session for refreshing it */
		if (is_dfs_link(npath)) {
		ses = root_ses = find_root_ses(vi, tcon, npath);
		if (IS_ERR(ses)) {
		rc = PTR_ERR(ses);
		root_ses = NULL;
		goto out;
		}
		} else {
		ses = tcon->ses;
		}

		if (unlikely(!ses->server->ops->get_dfs_refer)) {
		rc = -EOPNOTSUPP;
		} else {
		rc = tcon->ses->server->ops->get_dfs_refer(xid, tcon->ses, path,
		&refs, &numrefs,
		dc->dc_nlsc,
		rc = ses->server->ops->get_dfs_refer(xid, ses, path, &refs,
		&numrefs, dc->dc_nlsc,
		tcon->remap);
		if (!rc) {
		mutex_lock(&dfs_cache_list_lock);
		@@ -1323,9 +1434,11 @@ static void do_refresh_tcon(struct dfs_cache dc, struct cifs_tcon tcon)
		rc = PTR_ERR(ce);
		}
		}
		if (rc)
		cifs_dbg(FYI, "%s: failed to update expired entry\n", __func__);

		out:
		if (root_ses)
		cifs_put_smb_ses(root_ses);

		free_xid(xid);
		free_normalized_path(path, npath);
		}
		@@ -1333,9 +1446,6 @@ out:
		/*
		* Worker that will refresh DFS cache based on lowest TTL value from a DFS
		* referral.
		*
		* FIXME: ensure that all requests are sent to DFS root for refreshing the
		* cache.
		*/
		static void refresh_cache_worker(struct work_struct *work)
		{
		@@ -1356,7 +1466,7 @@ static void refresh_cache_worker(struct work_struct *work)
		goto next;
		get_tcons(server, &list);
		list_for_each_entry_safe(tcon, ntcon, &list, ulist) {
		do_refresh_tcon(dc, tcon);
		do_refresh_tcon(dc, vi, tcon);
		list_del_init(&tcon->ulist);
		cifs_put_tcon(tcon);
		}

fs/cifs/dfs_cache.h

+3 −2

Original line number	Diff line number	Diff line
		@@ -2,7 +2,7 @@
		/*
		* DFS referral cache routines
		*
		* Copyright (c) 2018 Paulo Alcantara <palcantara@suse.de>
		* Copyright (c) 2018-2019 Paulo Alcantara <palcantara@suse.de>
		*/

		#ifndef _CIFS_DFS_CACHE_H
		@@ -43,7 +43,8 @@ dfs_cache_noreq_update_tgthint(const char *path,
		extern int dfs_cache_get_tgt_referral(const char *path,
		const struct dfs_cache_tgt_iterator *it,
		struct dfs_info3_param *ref);
		extern int dfs_cache_add_vol(struct smb_vol vol, const char fullpath);
		extern int dfs_cache_add_vol(char mntdata, struct smb_vol vol,
		const char *fullpath);
		extern int dfs_cache_update_vol(const char *fullpath,
		struct TCP_Server_Info *server);
		extern void dfs_cache_del_vol(const char *fullpath);

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