SMB311: Add support for query info using posix extensions (level 100)

Adds support for better query info on dentry revalidation (using
the SMB3.1.1 POSIX extensions level 100).  Followon patch will
add support for translating the UID/GID from the SID and also
will add support for using the posix query info on lookup.

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>

6 files changed, 316 insertions, 2 deletions

diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h
index bd92070ca30c8e..b603da73f4f50d 100644
--- a/fs/cifs/cifsproto.h
+++ b/fs/cifs/cifsproto.h
@@ -198,6 +198,8 @@ extern struct inode *cifs_iget(struct super_block *sb,
 extern int cifs_get_inode_info(struct inode **inode, const char *full_path,
 			       FILE_ALL_INFO *data, struct super_block *sb,
 			       int xid, const struct cifs_fid *fid);
+extern int smb311_posix_get_inode_info(struct inode **pinode, const char *search_path,
+			struct super_block *sb, unsigned int xid);
 extern int cifs_get_inode_info_unix(struct inode **pinode,
 			const unsigned char *search_path,
 			struct super_block *sb, unsigned int xid);
diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index 5072bcaf4be114..c367195bdb0837 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -32,6 +32,7 @@
 #include "cifspdu.h"
 #include "cifsglob.h"
 #include "cifsproto.h"
+#include "smb2proto.h"
 #include "cifs_debug.h"
 #include "cifs_fs_sb.h"
 #include "cifs_unicode.h"
@@ -595,6 +596,62 @@ static int cifs_sfu_mode(struct cifs_fattr *fattr, const unsigned char *path,
 #endif
 }
 
+/* Fill a cifs_fattr struct with info from POSIX info struct */
+static void
+smb311_posix_info_to_fattr(struct cifs_fattr *fattr, struct smb311_posix_qinfo *info,
+			   struct super_block *sb, bool adjust_tz, bool symlink)
+{
+	struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
+	struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
+
+	memset(fattr, 0, sizeof(*fattr));
+
+	/* no fattr->flags to set */
+	fattr->cf_cifsattrs = le32_to_cpu(info->DosAttributes);
+	fattr->cf_uniqueid = le64_to_cpu(info->Inode);
+
+	if (info->LastAccessTime)
+		fattr->cf_atime = cifs_NTtimeToUnix(info->LastAccessTime);
+	else
+		ktime_get_coarse_real_ts64(&fattr->cf_atime);
+
+	fattr->cf_ctime = cifs_NTtimeToUnix(info->ChangeTime);
+	fattr->cf_mtime = cifs_NTtimeToUnix(info->LastWriteTime);
+
+	if (adjust_tz) {
+		fattr->cf_ctime.tv_sec += tcon->ses->server->timeAdj;
+		fattr->cf_mtime.tv_sec += tcon->ses->server->timeAdj;
+	}
+
+	fattr->cf_eof = le64_to_cpu(info->EndOfFile);
+	fattr->cf_bytes = le64_to_cpu(info->AllocationSize);
+	fattr->cf_createtime = le64_to_cpu(info->CreationTime);
+
+	fattr->cf_nlink = le32_to_cpu(info->HardLinks);
+	fattr->cf_mode = (umode_t) le32_to_cpu(info->Mode);
+	/* The srv fs device id is overridden on network mount so setting rdev isn't needed here */
+	/* fattr->cf_rdev = le32_to_cpu(info->DeviceId); */
+
+	if (symlink) {
+		fattr->cf_mode |= S_IFLNK;
+		fattr->cf_dtype = DT_LNK;
+	} else if (fattr->cf_cifsattrs & ATTR_DIRECTORY) {
+		fattr->cf_mode |= S_IFDIR;
+		fattr->cf_dtype = DT_DIR;
+	} else { /* file */
+		fattr->cf_mode |= S_IFREG;
+		fattr->cf_dtype = DT_REG;
+	}
+	/* else if reparse point ... TODO: add support for FIFO and blk dev; special file types */
+
+	fattr->cf_uid = cifs_sb->mnt_uid; /* TODO: map uid and gid from SID */
+	fattr->cf_gid = cifs_sb->mnt_gid;
+
+	cifs_dbg(FYI, "POSIX query info: mode 0x%x uniqueid 0x%llx nlink %d\n",
+		fattr->cf_mode, fattr->cf_uniqueid, fattr->cf_nlink);
+}
+
+
 /* Fill a cifs_fattr struct with info from FILE_ALL_INFO */
 static void
 cifs_all_info_to_fattr(struct cifs_fattr *fattr, FILE_ALL_INFO *info,
@@ -1023,6 +1080,121 @@ out:
 	return rc;
 }
 
+int
+smb311_posix_get_inode_info(struct inode **inode,
+		    const char *full_path,
+		    struct super_block *sb, unsigned int xid)
+{
+	struct cifs_tcon *tcon;
+	struct TCP_Server_Info *server;
+	struct tcon_link *tlink;
+	struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
+	bool adjust_tz = false;
+	struct cifs_fattr fattr = {0};
+	bool symlink = false;
+	struct smb311_posix_qinfo *data = NULL;
+	int rc = 0;
+	int tmprc = 0;
+
+	tlink = cifs_sb_tlink(cifs_sb);
+	if (IS_ERR(tlink))
+		return PTR_ERR(tlink);
+	tcon = tlink_tcon(tlink);
+	server = tcon->ses->server;
+
+	/*
+	 * 1. Fetch file metadata
+	 */
+
+	if (is_inode_cache_good(*inode)) {
+		cifs_dbg(FYI, "No need to revalidate cached inode sizes\n");
+		goto out;
+	}
+	data = kmalloc(sizeof(struct smb311_posix_qinfo), GFP_KERNEL);
+	if (!data) {
+		rc = -ENOMEM;
+		goto out;
+	}
+
+	rc = smb311_posix_query_path_info(xid, tcon, cifs_sb,
+						  full_path, data,
+						  &adjust_tz, &symlink);
+
+	/*
+	 * 2. Convert it to internal cifs metadata (fattr)
+	 */
+
+	switch (rc) {
+	case 0:
+		smb311_posix_info_to_fattr(&fattr, data, sb, adjust_tz, symlink);
+		break;
+	case -EREMOTE:
+		/* DFS link, no metadata available on this server */
+		cifs_create_dfs_fattr(&fattr, sb);
+		rc = 0;
+		break;
+	case -EACCES:
+		/*
+		 * For SMB2 and later the backup intent flag
+		 * is already sent if needed on open and there
+		 * is no path based FindFirst operation to use
+		 * to retry with so nothing we can do, bail out
+		 */
+		goto out;
+	default:
+		cifs_dbg(FYI, "%s: unhandled err rc %d\n", __func__, rc);
+		goto out;
+	}
+
+
+	/*
+	 * 4. Tweak fattr based on mount options
+	 */
+
+	/* check for Minshall+French symlinks */
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS) {
+		tmprc = check_mf_symlink(xid, tcon, cifs_sb, &fattr,
+					 full_path);
+		if (tmprc)
+			cifs_dbg(FYI, "check_mf_symlink: %d\n", tmprc);
+	}
+
+	/*
+	 * 5. Update inode with final fattr data
+	 */
+
+	if (!*inode) {
+		*inode = cifs_iget(sb, &fattr);
+		if (!*inode)
+			rc = -ENOMEM;
+	} else {
+		/* we already have inode, update it */
+
+		/* if uniqueid is different, return error */
+		if (unlikely(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM &&
+		    CIFS_I(*inode)->uniqueid != fattr.cf_uniqueid)) {
+			CIFS_I(*inode)->time = 0; /* force reval */
+			rc = -ESTALE;
+			goto out;
+		}
+
+		/* if filetype is different, return error */
+		if (unlikely(((*inode)->i_mode & S_IFMT) !=
+		    (fattr.cf_mode & S_IFMT))) {
+			CIFS_I(*inode)->time = 0; /* force reval */
+			rc = -ESTALE;
+			goto out;
+		}
+
+		cifs_fattr_to_inode(*inode, &fattr);
+	}
+out:
+	cifs_put_tlink(tlink);
+	kfree(data);
+	return rc;
+}
+
+
 static const struct inode_operations cifs_ipc_inode_ops = {
 	.lookup = cifs_lookup,
 };
@@ -2114,7 +2286,9 @@ int cifs_revalidate_dentry_attr(struct dentry *dentry)
 		 dentry, cifs_get_time(dentry), jiffies);
 
 again:
-	if (cifs_sb_master_tcon(CIFS_SB(sb))->unix_ext)
+	if (cifs_sb_master_tcon(CIFS_SB(sb))->posix_extensions)
+		rc = smb311_posix_get_inode_info(&inode, full_path, sb, xid);
+	else if (cifs_sb_master_tcon(CIFS_SB(sb))->unix_ext)
 		rc = cifs_get_inode_info_unix(&inode, full_path, sb, xid);
 	else
 		rc = cifs_get_inode_info(&inode, full_path, NULL, sb,
diff --git a/fs/cifs/smb2glob.h b/fs/cifs/smb2glob.h
index dd10f0ce4cd579..cf20f0b5d8363d 100644
--- a/fs/cifs/smb2glob.h
+++ b/fs/cifs/smb2glob.h
@@ -45,6 +45,7 @@
 #define SMB2_OP_HARDLINK 8
 #define SMB2_OP_SET_EOF 9
 #define SMB2_OP_RMDIR 10
+#define SMB2_OP_POSIX_QUERY_INFO 11
 
 /* Used when constructing chained read requests. */
 #define CHAINED_REQUEST 1
diff --git a/fs/cifs/smb2inode.c b/fs/cifs/smb2inode.c
index 0a116fc490a9cb..5154956311f0c9 100644
--- a/fs/cifs/smb2inode.c
+++ b/fs/cifs/smb2inode.c
@@ -166,6 +166,41 @@ smb2_compound_op(const unsigned int xid, struct cifs_tcon *tcon,
 		trace_smb3_query_info_compound_enter(xid, ses->Suid, tcon->tid,
 						     full_path);
 		break;
+	case SMB2_OP_POSIX_QUERY_INFO:
+		rqst[num_rqst].rq_iov = &vars->qi_iov[0];
+		rqst[num_rqst].rq_nvec = 1;
+
+		if (cfile)
+			rc = SMB2_query_info_init(tcon, server,
+				&rqst[num_rqst],
+				cfile->fid.persistent_fid,
+				cfile->fid.volatile_fid,
+				SMB_FIND_FILE_POSIX_INFO,
+				SMB2_O_INFO_FILE, 0,
+				/* TBD: fix following to allow for longer SIDs */
+				sizeof(struct smb311_posix_qinfo *) + (PATH_MAX * 2) +
+				(sizeof(struct cifs_sid) * 2), 0, NULL);
+		else {
+			rc = SMB2_query_info_init(tcon, server,
+				&rqst[num_rqst],
+				COMPOUND_FID,
+				COMPOUND_FID,
+				SMB_FIND_FILE_POSIX_INFO,
+				SMB2_O_INFO_FILE, 0,
+				sizeof(struct smb311_posix_qinfo *) + (PATH_MAX * 2) +
+				(sizeof(struct cifs_sid) * 2), 0, NULL);
+			if (!rc) {
+				smb2_set_next_command(tcon, &rqst[num_rqst]);
+				smb2_set_related(&rqst[num_rqst]);
+			}
+		}
+
+		if (rc)
+			goto finished;
+		num_rqst++;
+		trace_smb3_query_info_compound_enter(xid, ses->Suid, tcon->tid,
+						     full_path);
+		break;
 	case SMB2_OP_DELETE:
 		trace_smb3_delete_enter(xid, ses->Suid, tcon->tid, full_path);
 		break;
@@ -379,6 +414,26 @@ smb2_compound_op(const unsigned int xid, struct cifs_tcon *tcon,
 			trace_smb3_query_info_compound_done(xid, ses->Suid,
 						tcon->tid);
 		break;
+	case SMB2_OP_POSIX_QUERY_INFO:
+		if (rc == 0) {
+			qi_rsp = (struct smb2_query_info_rsp *)
+				rsp_iov[1].iov_base;
+			rc = smb2_validate_and_copy_iov(
+				le16_to_cpu(qi_rsp->OutputBufferOffset),
+				le32_to_cpu(qi_rsp->OutputBufferLength),
+				&rsp_iov[1], sizeof(struct smb311_posix_qinfo) /* add SIDs */, ptr);
+		}
+		if (rqst[1].rq_iov)
+			SMB2_query_info_free(&rqst[1]);
+		if (rqst[2].rq_iov)
+			SMB2_close_free(&rqst[2]);
+		if (rc)
+			trace_smb3_query_info_compound_err(xid,  ses->Suid,
+						tcon->tid, rc);
+		else
+			trace_smb3_query_info_compound_done(xid, ses->Suid,
+						tcon->tid);
+		break;
 	case SMB2_OP_DELETE:
 		if (rc)
 			trace_smb3_delete_err(xid,  ses->Suid, tcon->tid, rc);
@@ -512,6 +567,59 @@ out:
 	return rc;
 }
 
+
+int
+smb311_posix_query_path_info(const unsigned int xid, struct cifs_tcon *tcon,
+		     struct cifs_sb_info *cifs_sb, const char *full_path,
+		     struct smb311_posix_qinfo *data, bool *adjust_tz, bool *symlink)
+{
+	int rc;
+	__u32 create_options = 0;
+	struct cifsFileInfo *cfile;
+	struct smb311_posix_qinfo *smb2_data;
+
+	*adjust_tz = false;
+	*symlink = false;
+
+	/* BB TODO: Make struct larger when add support for parsing owner SIDs */
+	smb2_data = kzalloc(sizeof(struct smb311_posix_qinfo),
+			    GFP_KERNEL);
+	if (smb2_data == NULL)
+		return -ENOMEM;
+
+	/*
+	 * BB TODO: Add support for using the cached root handle.
+	 * Create SMB2_query_posix_info worker function to do non-compounded query
+	 * when we already have an open file handle for this. For now this is fast enough
+	 * (always using the compounded version).
+	 */
+
+	cifs_get_readable_path(tcon, full_path, &cfile);
+	rc = smb2_compound_op(xid, tcon, cifs_sb, full_path,
+			      FILE_READ_ATTRIBUTES, FILE_OPEN, create_options,
+			      ACL_NO_MODE, smb2_data, SMB2_OP_POSIX_QUERY_INFO, cfile);
+	if (rc == -EOPNOTSUPP) {
+		/* BB TODO: When support for special files added to Samba re-verify this path */
+		*symlink = true;
+		create_options |= OPEN_REPARSE_POINT;
+
+		/* Failed on a symbolic link - query a reparse point info */
+		rc = smb2_compound_op(xid, tcon, cifs_sb, full_path,
+				      FILE_READ_ATTRIBUTES, FILE_OPEN,
+				      create_options, ACL_NO_MODE,
+				      smb2_data, SMB2_OP_POSIX_QUERY_INFO, NULL);
+	}
+	if (rc)
+		goto out;
+
+	 /* TODO: will need to allow for the 2 SIDs when add support for getting owner UID/GID */
+	memcpy(data, smb2_data, sizeof(struct smb311_posix_qinfo));
+
+out:
+	kfree(smb2_data);
+	return rc;
+}
+
 int
 smb2_mkdir(const unsigned int xid, struct inode *parent_inode, umode_t mode,
 	   struct cifs_tcon *tcon, const char *name,
diff --git a/fs/cifs/smb2pdu.h b/fs/cifs/smb2pdu.h
index 3b0e6acf9d7d9d..236814d612487b 100644
--- a/fs/cifs/smb2pdu.h
+++ b/fs/cifs/smb2pdu.h
@@ -1653,7 +1653,7 @@ struct create_posix_rsp {
 } __packed;
 
 /*
- * SMB2-only POSIX info level
+ * SMB2-only POSIX info level for query dir
  *
  * See posix_info_sid_size(), posix_info_extra_size() and
  * posix_info_parse() to help with the handling of this struct.
@@ -1683,6 +1683,31 @@ struct smb2_posix_info {
 	 */
 } __packed;
 
+/* Level 100 query info */
+struct smb311_posix_qinfo {
+	__le64 CreationTime;
+	__le64 LastAccessTime;
+	__le64 LastWriteTime;
+	__le64 ChangeTime;
+	__le64 EndOfFile;
+	__le64 AllocationSize;
+	__le32 DosAttributes;
+	__le64 Inode;
+	__le32 DeviceId;
+	__le32 Zero;
+	/* beginning of POSIX Create Context Response */
+	__le32 HardLinks;
+	__le32 ReparseTag;
+	__le32 Mode;
+	u8     Sids[];
+	/*
+	 * var sized owner SID
+	 * var sized group SID
+	 * le32 filenamelength
+	 * u8  filename[]
+	 */
+} __packed;
+
 /*
  * Parsed version of the above struct. Allows direct access to the
  * variable length fields
diff --git a/fs/cifs/smb2proto.h b/fs/cifs/smb2proto.h
index 71ba74792c9ef7..a5c6da59847e28 100644
--- a/fs/cifs/smb2proto.h
+++ b/fs/cifs/smb2proto.h
@@ -289,6 +289,10 @@ extern int smb2_query_info_compound(const unsigned int xid,
 				    u32 class, u32 type, u32 output_len,
 				    struct kvec *rsp, int *buftype,
 				    struct cifs_sb_info *cifs_sb);
+/* query path info from the server using SMB311 POSIX extensions*/
+extern int smb311_posix_query_path_info(const unsigned int xid, struct cifs_tcon *tcon,
+			struct cifs_sb_info *sb, const char *path, struct smb311_posix_qinfo *qinf,
+			bool *adjust_tx, bool *symlink);
 int posix_info_parse(const void *beg, const void *end,
 		     struct smb2_posix_info_parsed *out);
 int posix_info_sid_size(const void *beg, const void *end);