cifs: introduce cifs_dirent

Introduce a generic directory entry structure, and factor the parsing
of the various on the wire structures that can represent one into
a common helper.  Switch cifs_entry_is_dot over to use it as a start.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>

1 files changed, 125 insertions, 69 deletions

diff --git a/fs/cifs/readdir.c b/fs/cifs/readdir.c
index 04c9b9fbebb4..67fc1199699f 100644
--- a/fs/cifs/readdir.c
+++ b/fs/cifs/readdir.c
@@ -4,6 +4,7 @@
  *   Directory search handling
  *
  *   Copyright (C) International Business Machines  Corp., 2004, 2008
+ *   Copyright (C) Red Hat, Inc., 2011
  *   Author(s): Steve French (sfrench@us.ibm.com)
  *
  *   This library is free software; you can redistribute it and/or modify
@@ -290,10 +291,10 @@ error_exit:
 }
 
 /* return length of unicode string in bytes */
-static int cifs_unicode_bytelen(char *str)
+static int cifs_unicode_bytelen(const char *str)
 {
         int len;
-        __le16 *ustr = (__le16 *)str;
+        const __le16 *ustr = (const __le16 *)str;
 
         for (len = 0; len <= PATH_MAX; len++) {
                 if (ustr[len] == 0)
@@ -334,78 +335,128 @@ static char *nxt_dir_entry(char *old_entry, char *end_of_smb, int level)
 
 }
 
+struct cifs_dirent {
+        const char      *name;
+        size_t          namelen;
+        u32             resume_key;
+        u64             ino;
+};
+
+static void cifs_fill_dirent_unix(struct cifs_dirent *de,
+                const FILE_UNIX_INFO *info, bool is_unicode)
+{
+        de->name = &info->FileName[0];
+        if (is_unicode)
+                de->namelen = cifs_unicode_bytelen(de->name);
+        else
+                de->namelen = strnlen(de->name, PATH_MAX);
+        de->resume_key = info->ResumeKey;
+        de->ino = le64_to_cpu(info->basic.UniqueId);
+}
+
+static void cifs_fill_dirent_dir(struct cifs_dirent *de,
+                const FILE_DIRECTORY_INFO *info)
+{
+        de->name = &info->FileName[0];
+        de->namelen = le32_to_cpu(info->FileNameLength);
+        de->resume_key = info->FileIndex;
+}
+
+static void cifs_fill_dirent_full(struct cifs_dirent *de,
+                const FILE_FULL_DIRECTORY_INFO *info)
+{
+        de->name = &info->FileName[0];
+        de->namelen = le32_to_cpu(info->FileNameLength);
+        de->resume_key = info->FileIndex;
+}
+
+static void cifs_fill_dirent_search(struct cifs_dirent *de,
+                const SEARCH_ID_FULL_DIR_INFO *info)
+{
+        de->name = &info->FileName[0];
+        de->namelen = le32_to_cpu(info->FileNameLength);
+        de->resume_key = info->FileIndex;
+        de->ino = le64_to_cpu(info->UniqueId);
+}
+
+static void cifs_fill_dirent_both(struct cifs_dirent *de,
+                const FILE_BOTH_DIRECTORY_INFO *info)
+{
+        de->name = &info->FileName[0];
+        de->namelen = le32_to_cpu(info->FileNameLength);
+        de->resume_key = info->FileIndex;
+}
+
+static void cifs_fill_dirent_std(struct cifs_dirent *de,
+                const FIND_FILE_STANDARD_INFO *info)
+{
+        de->name = &info->FileName[0];
+        /* one byte length, no endianess conversion */
+        de->namelen = info->FileNameLength;
+        de->resume_key = info->ResumeKey;
+}
+
+static int cifs_fill_dirent(struct cifs_dirent *de, const void *info,
+                u16 level, bool is_unicode)
+{
+        memset(de, 0, sizeof(*de));
+
+        switch (level) {
+        case SMB_FIND_FILE_UNIX:
+                cifs_fill_dirent_unix(de, info, is_unicode);
+                break;
+        case SMB_FIND_FILE_DIRECTORY_INFO:
+                cifs_fill_dirent_dir(de, info);
+                break;
+        case SMB_FIND_FILE_FULL_DIRECTORY_INFO:
+                cifs_fill_dirent_full(de, info);
+                break;
+        case SMB_FIND_FILE_ID_FULL_DIR_INFO:
+                cifs_fill_dirent_search(de, info);
+                break;
+        case SMB_FIND_FILE_BOTH_DIRECTORY_INFO:
+                cifs_fill_dirent_both(de, info);
+                break;
+        case SMB_FIND_FILE_INFO_STANDARD:
+                cifs_fill_dirent_std(de, info);
+                break;
+        default:
+                cFYI(1, "Unknown findfirst level %d", level);
+                return -EINVAL;
+        }
+
+        return 0;
+}
+
 #define UNICODE_DOT cpu_to_le16(0x2e)
 
 /* return 0 if no match and 1 for . (current directory) and 2 for .. (parent) */
-static int cifs_entry_is_dot(char *current_entry, struct cifsFileInfo *cfile)
+static int cifs_entry_is_dot(struct cifs_dirent *de, bool is_unicode)
 {
         int rc = 0;
-        char *filename = NULL;
-        int len = 0;
 
-        if (cfile->srch_inf.info_level == SMB_FIND_FILE_UNIX) {
-                FILE_UNIX_INFO *pFindData = (FILE_UNIX_INFO *)current_entry;
-                filename = &pFindData->FileName[0];
-                if (cfile->srch_inf.unicode) {
-                        len = cifs_unicode_bytelen(filename);
-                } else {
-                        /* BB should we make this strnlen of PATH_MAX? */
-                        len = strnlen(filename, 5);
-                }
-        } else if (cfile->srch_inf.info_level == SMB_FIND_FILE_DIRECTORY_INFO) {
-                FILE_DIRECTORY_INFO *pFindData =
-                        (FILE_DIRECTORY_INFO *)current_entry;
-                filename = &pFindData->FileName[0];
-                len = le32_to_cpu(pFindData->FileNameLength);
-        } else if (cfile->srch_inf.info_level ==
-                        SMB_FIND_FILE_FULL_DIRECTORY_INFO) {
-                FILE_FULL_DIRECTORY_INFO *pFindData =
-                        (FILE_FULL_DIRECTORY_INFO *)current_entry;
-                filename = &pFindData->FileName[0];
-                len = le32_to_cpu(pFindData->FileNameLength);
-        } else if (cfile->srch_inf.info_level ==
-                        SMB_FIND_FILE_ID_FULL_DIR_INFO) {
-                SEARCH_ID_FULL_DIR_INFO *pFindData =
-                        (SEARCH_ID_FULL_DIR_INFO *)current_entry;
-                filename = &pFindData->FileName[0];
-                len = le32_to_cpu(pFindData->FileNameLength);
-        } else if (cfile->srch_inf.info_level ==
-                        SMB_FIND_FILE_BOTH_DIRECTORY_INFO) {
-                FILE_BOTH_DIRECTORY_INFO *pFindData =
-                        (FILE_BOTH_DIRECTORY_INFO *)current_entry;
-                filename = &pFindData->FileName[0];
-                len = le32_to_cpu(pFindData->FileNameLength);
-        } else if (cfile->srch_inf.info_level == SMB_FIND_FILE_INFO_STANDARD) {
-                FIND_FILE_STANDARD_INFO *pFindData =
-                        (FIND_FILE_STANDARD_INFO *)current_entry;
-                filename = &pFindData->FileName[0];
-                len = pFindData->FileNameLength;
-        } else {
-                cFYI(1, "Unknown findfirst level %d",
-                         cfile->srch_inf.info_level);
-        }
+        if (!de->name)
+                return 0;
 
-        if (filename) {
-                if (cfile->srch_inf.unicode) {
-                        __le16 *ufilename = (__le16 *)filename;
-                        if (len == 2) {
-                                /* check for . */
-                                if (ufilename[0] == UNICODE_DOT)
-                                        rc = 1;
-                        } else if (len == 4) {
-                                /* check for .. */
-                                if ((ufilename[0] == UNICODE_DOT)
-                                   && (ufilename[1] == UNICODE_DOT))
-                                        rc = 2;
-                        }
-                } else /* ASCII */ {
-                        if (len == 1) {
-                                if (filename[0] == '.')
-                                        rc = 1;
-                        } else if (len == 2) {
-                                if ((filename[0] == '.') && (filename[1] == '.'))
-                                        rc = 2;
-                        }
+        if (is_unicode) {
+                __le16 *ufilename = (__le16 *)de->name;
+                if (de->namelen == 2) {
+                        /* check for . */
+                        if (ufilename[0] == UNICODE_DOT)
+                                rc = 1;
+                } else if (de->namelen == 4) {
+                        /* check for .. */
+                        if (ufilename[0] == UNICODE_DOT &&
+                            ufilename[1] == UNICODE_DOT)
+                                rc = 2;
+                }
+        } else /* ASCII */ {
+                if (de->namelen == 1) {
+                        if (de->name[0] == '.')
+                                rc = 1;
+                } else if (de->namelen == 2) {
+                        if (de->name[0] == '.' && de->name[1] == '.')
+                                rc = 2;
                 }
         }
 
@@ -687,6 +738,7 @@ static int cifs_filldir(char *find_entry, struct file *file, filldir_t filldir,
         struct cifsFileInfo *file_info = file->private_data;
         struct super_block *sb = file->f_path.dentry->d_sb;
         struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
+        struct cifs_dirent de = { NULL, };
         struct cifs_fattr fattr;
         struct dentry *dentry;
         struct qstr name;
@@ -694,9 +746,13 @@ static int cifs_filldir(char *find_entry, struct file *file, filldir_t filldir,
         u64 inum;
         ino_t ino;
 
+        rc = cifs_fill_dirent(&de, find_entry, file_info->srch_inf.info_level,
+                              file_info->srch_inf.unicode);
+        if (rc)
+                return rc;
+
         /* skip . and .. since we added them first */
-        rc = cifs_entry_is_dot(find_entry, file_info);
-        if (rc != 0)
+        if (cifs_entry_is_dot(&de, file_info->srch_inf.unicode))
                 return 0;
 
         name.name = scratch_buf;