davidlt/kernel-ark
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity
3c48f23ada
kernel-ark/fs/cifs/readdir.c
Jeff Layton fbec9ab952 cifs: vary timeout on writes past EOF based on offset (try #5) 
This is the fourth version of this patch:

The first three generated a compiler warning asking for explicit curly
braces.

The first two didn't handle update the size correctly when writes that
didn't start at the eof were done.

The first patch also didn't update the size correctly when it explicitly
set via truncate().

This patch adds code to track the client's current understanding of the
size of the file on the server separate from the i_size, and then to use
this info to semi-intelligently set the timeout for writes past the EOF.

This helps prevent timeouts when trying to write large, sparse files on
windows servers.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2009-04-17 01:26:49 +00:00

1114 lines
34 KiB
C
Raw Blame History

/*
* fs/cifs/readdir.c
*
* Directory search handling
*
* Copyright (C) International Business Machines Corp., 2004, 2008
* Author(s): Steve French (sfrench@us.ibm.com)
*
* This library is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published
* by the Free Software Foundation; either version 2.1 of the License, or
* (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
* the GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/fs.h>
#include <linux/pagemap.h>
#include <linux/stat.h>
#include "cifspdu.h"
#include "cifsglob.h"
#include "cifsproto.h"
#include "cifs_unicode.h"
#include "cifs_debug.h"
#include "cifs_fs_sb.h"
#include "cifsfs.h"
#ifdef CONFIG_CIFS_DEBUG2
static void dump_cifs_file_struct(struct file *file, char *label)
{
struct cifsFileInfo *cf;
if (file) {
cf = file->private_data;
if (cf == NULL) {
cFYI(1, ("empty cifs private file data"));
return;
}
if (cf->invalidHandle)
cFYI(1, ("invalid handle"));
if (cf->srch_inf.endOfSearch)
cFYI(1, ("end of search"));
if (cf->srch_inf.emptyDir)
cFYI(1, ("empty dir"));
}
}
#else
static inline void dump_cifs_file_struct(struct file *file, char *label)
{
}
#endif /* DEBUG2 */
/* Returns 1 if new inode created, 2 if both dentry and inode were */
/* Might check in the future if inode number changed so we can rehash inode */
static int
construct_dentry(struct qstr *qstring, struct file *file,
struct inode **ptmp_inode, struct dentry **pnew_dentry,
__u64 *inum)
{
struct dentry *tmp_dentry = NULL;
struct super_block *sb = file->f_path.dentry->d_sb;
int rc = 0;
cFYI(1, ("For %s", qstring->name));
qstring->hash = full_name_hash(qstring->name, qstring->len);
tmp_dentry = d_lookup(file->f_path.dentry, qstring);
if (tmp_dentry) {
/* BB: overwrite old name? i.e. tmp_dentry->d_name and
* tmp_dentry->d_name.len??
*/
cFYI(0, ("existing dentry with inode 0x%p",
tmp_dentry->d_inode));
*ptmp_inode = tmp_dentry->d_inode;
if (*ptmp_inode == NULL) {
*ptmp_inode = cifs_new_inode(sb, inum);
if (*ptmp_inode == NULL)
return rc;
rc = 1;
}
} else {
tmp_dentry = d_alloc(file->f_path.dentry, qstring);
if (tmp_dentry == NULL) {
cERROR(1, ("Failed allocating dentry"));
*ptmp_inode = NULL;
return rc;
}
if (CIFS_SB(sb)->tcon->nocase)
tmp_dentry->d_op = &cifs_ci_dentry_ops;
else
tmp_dentry->d_op = &cifs_dentry_ops;
*ptmp_inode = cifs_new_inode(sb, inum);
if (*ptmp_inode == NULL)
return rc;
rc = 2;
}
tmp_dentry->d_time = jiffies;
*pnew_dentry = tmp_dentry;
return rc;
}
static void AdjustForTZ(struct cifsTconInfo *tcon, struct inode *inode)
{
if ((tcon) && (tcon->ses) && (tcon->ses->server)) {
inode->i_ctime.tv_sec += tcon->ses->server->timeAdj;
inode->i_mtime.tv_sec += tcon->ses->server->timeAdj;
inode->i_atime.tv_sec += tcon->ses->server->timeAdj;
}
return;
}
static void fill_in_inode(struct inode *tmp_inode, int new_buf_type,
char *buf, unsigned int *pobject_type, int isNewInode)
{
loff_t local_size;
struct timespec local_mtime;
struct cifsInodeInfo *cifsInfo = CIFS_I(tmp_inode);
struct cifs_sb_info *cifs_sb = CIFS_SB(tmp_inode->i_sb);
__u32 attr;
__u64 allocation_size;
__u64 end_of_file;
umode_t default_mode;
/* save mtime and size */
local_mtime = tmp_inode->i_mtime;
local_size = tmp_inode->i_size;
if (new_buf_type) {
FILE_DIRECTORY_INFO *pfindData = (FILE_DIRECTORY_INFO *)buf;
attr = le32_to_cpu(pfindData->ExtFileAttributes);
allocation_size = le64_to_cpu(pfindData->AllocationSize);
end_of_file = le64_to_cpu(pfindData->EndOfFile);
tmp_inode->i_atime =
cifs_NTtimeToUnix(le64_to_cpu(pfindData->LastAccessTime));
tmp_inode->i_mtime =
cifs_NTtimeToUnix(le64_to_cpu(pfindData->LastWriteTime));
tmp_inode->i_ctime =
cifs_NTtimeToUnix(le64_to_cpu(pfindData->ChangeTime));
} else { /* legacy, OS2 and DOS style */
/* struct timespec ts;*/
FIND_FILE_STANDARD_INFO *pfindData =
(FIND_FILE_STANDARD_INFO *)buf;
tmp_inode->i_mtime = cnvrtDosUnixTm(
le16_to_cpu(pfindData->LastWriteDate),
le16_to_cpu(pfindData->LastWriteTime));
tmp_inode->i_atime = cnvrtDosUnixTm(
le16_to_cpu(pfindData->LastAccessDate),
le16_to_cpu(pfindData->LastAccessTime));
tmp_inode->i_ctime = cnvrtDosUnixTm(
le16_to_cpu(pfindData->LastWriteDate),
le16_to_cpu(pfindData->LastWriteTime));
AdjustForTZ(cifs_sb->tcon, tmp_inode);
attr = le16_to_cpu(pfindData->Attributes);
allocation_size = le32_to_cpu(pfindData->AllocationSize);
end_of_file = le32_to_cpu(pfindData->DataSize);
}
/* Linux can not store file creation time unfortunately so ignore it */
cifsInfo->cifsAttrs = attr;
#ifdef CONFIG_CIFS_EXPERIMENTAL
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_ACL) {
/* get more accurate mode via ACL - so force inode refresh */
cifsInfo->time = 0;
} else
#endif /* CONFIG_CIFS_EXPERIMENTAL */
cifsInfo->time = jiffies;
/* treat dos attribute of read-only as read-only mode bit e.g. 555? */
/* 2767 perms - indicate mandatory locking */
/* BB fill in uid and gid here? with help from winbind?
or retrieve from NTFS stream extended attribute */
if (atomic_read(&cifsInfo->inUse) == 0) {
tmp_inode->i_uid = cifs_sb->mnt_uid;
tmp_inode->i_gid = cifs_sb->mnt_gid;
}
if (attr & ATTR_DIRECTORY)
default_mode = cifs_sb->mnt_dir_mode;
else
default_mode = cifs_sb->mnt_file_mode;
/* set initial permissions */
if ((atomic_read(&cifsInfo->inUse) == 0) ||
(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DYNPERM) == 0)
tmp_inode->i_mode = default_mode;
else {
/* just reenable write bits if !ATTR_READONLY */
if ((tmp_inode->i_mode & S_IWUGO) == 0 &&
(attr & ATTR_READONLY) == 0)
tmp_inode->i_mode |= (S_IWUGO & default_mode);
tmp_inode->i_mode &= ~S_IFMT;
}
/* clear write bits if ATTR_READONLY is set */
if (attr & ATTR_READONLY)
tmp_inode->i_mode &= ~S_IWUGO;
/* set inode type */
if ((attr & ATTR_SYSTEM) &&
(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL)) {
if (end_of_file == 0) {
tmp_inode->i_mode |= S_IFIFO;
*pobject_type = DT_FIFO;
} else {
/*
* trying to get the type can be slow, so just call
* this a regular file for now, and mark for reval
*/
tmp_inode->i_mode |= S_IFREG;
*pobject_type = DT_REG;
cifsInfo->time = 0;
}
} else {
if (attr & ATTR_DIRECTORY) {
tmp_inode->i_mode |= S_IFDIR;
*pobject_type = DT_DIR;
} else {
tmp_inode->i_mode |= S_IFREG;
*pobject_type = DT_REG;
}
}
/* can not fill in nlink here as in qpathinfo version and Unx search */
if (atomic_read(&cifsInfo->inUse) == 0)
atomic_set(&cifsInfo->inUse, 1);
cifsInfo->server_eof = end_of_file;
spin_lock(&tmp_inode->i_lock);
if (is_size_safe_to_change(cifsInfo, end_of_file)) {
/* can not safely change the file size here if the
client is writing to it due to potential races */
i_size_write(tmp_inode, end_of_file);
/* 512 bytes (2**9) is the fake blocksize that must be used */
/* for this calculation, even though the reported blocksize is larger */
tmp_inode->i_blocks = (512 - 1 + allocation_size) >> 9;
}
spin_unlock(&tmp_inode->i_lock);
if (allocation_size < end_of_file)
cFYI(1, ("May be sparse file, allocation less than file size"));
cFYI(1, ("File Size %ld and blocks %llu",
(unsigned long)tmp_inode->i_size,
(unsigned long long)tmp_inode->i_blocks));
if (S_ISREG(tmp_inode->i_mode)) {
cFYI(1, ("File inode"));
tmp_inode->i_op = &cifs_file_inode_ops;
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DIRECT_IO) {
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
tmp_inode->i_fop = &cifs_file_direct_nobrl_ops;
else
tmp_inode->i_fop = &cifs_file_direct_ops;
} else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
tmp_inode->i_fop = &cifs_file_nobrl_ops;
else
tmp_inode->i_fop = &cifs_file_ops;
if ((cifs_sb->tcon) && (cifs_sb->tcon->ses) &&
(cifs_sb->tcon->ses->server->maxBuf <
PAGE_CACHE_SIZE + MAX_CIFS_HDR_SIZE))
tmp_inode->i_data.a_ops = &cifs_addr_ops_smallbuf;
else
tmp_inode->i_data.a_ops = &cifs_addr_ops;
if (isNewInode)
return; /* No sense invalidating pages for new inode
since have not started caching readahead file
data yet */
if (timespec_equal(&tmp_inode->i_mtime, &local_mtime) &&
(local_size == tmp_inode->i_size)) {
cFYI(1, ("inode exists but unchanged"));
} else {
/* file may have changed on server */
cFYI(1, ("invalidate inode, readdir detected change"));
invalidate_remote_inode(tmp_inode);
}
} else if (S_ISDIR(tmp_inode->i_mode)) {
cFYI(1, ("Directory inode"));
tmp_inode->i_op = &cifs_dir_inode_ops;
tmp_inode->i_fop = &cifs_dir_ops;
} else if (S_ISLNK(tmp_inode->i_mode)) {
cFYI(1, ("Symbolic Link inode"));
tmp_inode->i_op = &cifs_symlink_inode_ops;
} else {
cFYI(1, ("Init special inode"));
init_special_inode(tmp_inode, tmp_inode->i_mode,
tmp_inode->i_rdev);
}
}
static void unix_fill_in_inode(struct inode *tmp_inode,
FILE_UNIX_INFO *pfindData, unsigned int *pobject_type, int isNewInode)
{
loff_t local_size;
struct timespec local_mtime;
struct cifsInodeInfo *cifsInfo = CIFS_I(tmp_inode);
struct cifs_sb_info *cifs_sb = CIFS_SB(tmp_inode->i_sb);
__u32 type = le32_to_cpu(pfindData->Type);
__u64 num_of_bytes = le64_to_cpu(pfindData->NumOfBytes);
__u64 end_of_file = le64_to_cpu(pfindData->EndOfFile);
cifsInfo->time = jiffies;
atomic_inc(&cifsInfo->inUse);
/* save mtime and size */
local_mtime = tmp_inode->i_mtime;
local_size = tmp_inode->i_size;
tmp_inode->i_atime =
cifs_NTtimeToUnix(le64_to_cpu(pfindData->LastAccessTime));
tmp_inode->i_mtime =
cifs_NTtimeToUnix(le64_to_cpu(pfindData->LastModificationTime));
tmp_inode->i_ctime =
cifs_NTtimeToUnix(le64_to_cpu(pfindData->LastStatusChange));
tmp_inode->i_mode = le64_to_cpu(pfindData->Permissions);
/* since we set the inode type below we need to mask off type
to avoid strange results if bits above were corrupt */
tmp_inode->i_mode &= ~S_IFMT;
if (type == UNIX_FILE) {
*pobject_type = DT_REG;
tmp_inode->i_mode |= S_IFREG;
} else if (type == UNIX_SYMLINK) {
*pobject_type = DT_LNK;
tmp_inode->i_mode |= S_IFLNK;
} else if (type == UNIX_DIR) {
*pobject_type = DT_DIR;
tmp_inode->i_mode |= S_IFDIR;
} else if (type == UNIX_CHARDEV) {
*pobject_type = DT_CHR;
tmp_inode->i_mode |= S_IFCHR;
tmp_inode->i_rdev = MKDEV(le64_to_cpu(pfindData->DevMajor),
le64_to_cpu(pfindData->DevMinor) & MINORMASK);
} else if (type == UNIX_BLOCKDEV) {
*pobject_type = DT_BLK;
tmp_inode->i_mode |= S_IFBLK;
tmp_inode->i_rdev = MKDEV(le64_to_cpu(pfindData->DevMajor),
le64_to_cpu(pfindData->DevMinor) & MINORMASK);
} else if (type == UNIX_FIFO) {
*pobject_type = DT_FIFO;
tmp_inode->i_mode |= S_IFIFO;
} else if (type == UNIX_SOCKET) {
*pobject_type = DT_SOCK;
tmp_inode->i_mode |= S_IFSOCK;
} else {
/* safest to just call it a file */
*pobject_type = DT_REG;
tmp_inode->i_mode |= S_IFREG;
cFYI(1, ("unknown inode type %d", type));
}
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_OVERR_UID)
tmp_inode->i_uid = cifs_sb->mnt_uid;
else
tmp_inode->i_uid = le64_to_cpu(pfindData->Uid);
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_OVERR_GID)
tmp_inode->i_gid = cifs_sb->mnt_gid;
else
tmp_inode->i_gid = le64_to_cpu(pfindData->Gid);
tmp_inode->i_nlink = le64_to_cpu(pfindData->Nlinks);
cifsInfo->server_eof = end_of_file;
spin_lock(&tmp_inode->i_lock);
if (is_size_safe_to_change(cifsInfo, end_of_file)) {
/* can not safely change the file size here if the
client is writing to it due to potential races */
i_size_write(tmp_inode, end_of_file);
/* 512 bytes (2**9) is the fake blocksize that must be used */
/* for this calculation, not the real blocksize */
tmp_inode->i_blocks = (512 - 1 + num_of_bytes) >> 9;
}
spin_unlock(&tmp_inode->i_lock);
if (S_ISREG(tmp_inode->i_mode)) {
cFYI(1, ("File inode"));
tmp_inode->i_op = &cifs_file_inode_ops;
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DIRECT_IO) {
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
tmp_inode->i_fop = &cifs_file_direct_nobrl_ops;
else
tmp_inode->i_fop = &cifs_file_direct_ops;
} else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
tmp_inode->i_fop = &cifs_file_nobrl_ops;
else
tmp_inode->i_fop = &cifs_file_ops;
if ((cifs_sb->tcon) && (cifs_sb->tcon->ses) &&
(cifs_sb->tcon->ses->server->maxBuf <
PAGE_CACHE_SIZE + MAX_CIFS_HDR_SIZE))
tmp_inode->i_data.a_ops = &cifs_addr_ops_smallbuf;
else
tmp_inode->i_data.a_ops = &cifs_addr_ops;
if (isNewInode)
return; /* No sense invalidating pages for new inode
since we have not started caching readahead
file data for it yet */
if (timespec_equal(&tmp_inode->i_mtime, &local_mtime) &&
(local_size == tmp_inode->i_size)) {
cFYI(1, ("inode exists but unchanged"));
} else {
/* file may have changed on server */
cFYI(1, ("invalidate inode, readdir detected change"));
invalidate_remote_inode(tmp_inode);
}
} else if (S_ISDIR(tmp_inode->i_mode)) {
cFYI(1, ("Directory inode"));
tmp_inode->i_op = &cifs_dir_inode_ops;
tmp_inode->i_fop = &cifs_dir_ops;
} else if (S_ISLNK(tmp_inode->i_mode)) {
cFYI(1, ("Symbolic Link inode"));
tmp_inode->i_op = &cifs_symlink_inode_ops;
/* tmp_inode->i_fop = *//* do not need to set to anything */
} else {
cFYI(1, ("Special inode"));
init_special_inode(tmp_inode, tmp_inode->i_mode,
tmp_inode->i_rdev);
}
}
static int initiate_cifs_search(const int xid, struct file *file)
{
int rc = 0;
char *full_path;
struct cifsFileInfo *cifsFile;
struct cifs_sb_info *cifs_sb;
struct cifsTconInfo *pTcon;
if (file->private_data == NULL) {
file->private_data =
kzalloc(sizeof(struct cifsFileInfo), GFP_KERNEL);
}
if (file->private_data == NULL)
return -ENOMEM;
cifsFile = file->private_data;
cifsFile->invalidHandle = true;
cifsFile->srch_inf.endOfSearch = false;
cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
if (cifs_sb == NULL)
return -EINVAL;
pTcon = cifs_sb->tcon;
if (pTcon == NULL)
return -EINVAL;
full_path = build_path_from_dentry(file->f_path.dentry);
if (full_path == NULL)
return -ENOMEM;
cFYI(1, ("Full path: %s start at: %lld", full_path, file->f_pos));
ffirst_retry:
/* test for Unix extensions */
/* but now check for them on the share/mount not on the SMB session */
/* if (pTcon->ses->capabilities & CAP_UNIX) { */
if (pTcon->unix_ext)
cifsFile->srch_inf.info_level = SMB_FIND_FILE_UNIX;
else if ((pTcon->ses->capabilities &
(CAP_NT_SMBS | CAP_NT_FIND)) == 0) {
cifsFile->srch_inf.info_level = SMB_FIND_FILE_INFO_STANDARD;
} else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) {
cifsFile->srch_inf.info_level = SMB_FIND_FILE_ID_FULL_DIR_INFO;
} else /* not srvinos - BB fixme add check for backlevel? */ {
cifsFile->srch_inf.info_level = SMB_FIND_FILE_DIRECTORY_INFO;
}
rc = CIFSFindFirst(xid, pTcon, full_path, cifs_sb->local_nls,
&cifsFile->netfid, &cifsFile->srch_inf,
cifs_sb->mnt_cifs_flags &
CIFS_MOUNT_MAP_SPECIAL_CHR, CIFS_DIR_SEP(cifs_sb));
if (rc == 0)
cifsFile->invalidHandle = false;
if ((rc == -EOPNOTSUPP) &&
(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) {
cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SERVER_INUM;
goto ffirst_retry;
}
kfree(full_path);
return rc;
}
/* return length of unicode string in bytes */
static int cifs_unicode_bytelen(char *str)
{
int len;
__le16 *ustr = (__le16 *)str;
for (len = 0; len <= PATH_MAX; len++) {
if (ustr[len] == 0)
return len << 1;
}
cFYI(1, ("Unicode string longer than PATH_MAX found"));
return len << 1;
}
static char *nxt_dir_entry(char *old_entry, char *end_of_smb, int level)
{
char *new_entry;
FILE_DIRECTORY_INFO *pDirInfo = (FILE_DIRECTORY_INFO *)old_entry;
if (level == SMB_FIND_FILE_INFO_STANDARD) {
FIND_FILE_STANDARD_INFO *pfData;
pfData = (FIND_FILE_STANDARD_INFO *)pDirInfo;
new_entry = old_entry + sizeof(FIND_FILE_STANDARD_INFO) +
pfData->FileNameLength;
} else
new_entry = old_entry + le32_to_cpu(pDirInfo->NextEntryOffset);
cFYI(1, ("new entry %p old entry %p", new_entry, old_entry));
/* validate that new_entry is not past end of SMB */
if (new_entry >= end_of_smb) {
cERROR(1,
("search entry %p began after end of SMB %p old entry %p",
new_entry, end_of_smb, old_entry));
return NULL;
} else if (((level == SMB_FIND_FILE_INFO_STANDARD) &&
(new_entry + sizeof(FIND_FILE_STANDARD_INFO) > end_of_smb))
|| ((level != SMB_FIND_FILE_INFO_STANDARD) &&
(new_entry + sizeof(FILE_DIRECTORY_INFO) > end_of_smb))) {
cERROR(1, ("search entry %p extends after end of SMB %p",
new_entry, end_of_smb));
return NULL;
} else
return new_entry;
}
#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)
{
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 (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;
}
}
}
return rc;
}
/* Check if directory that we are searching has changed so we can decide
whether we can use the cached search results from the previous search */
static int is_dir_changed(struct file *file)
{
struct inode *inode = file->f_path.dentry->d_inode;
struct cifsInodeInfo *cifsInfo = CIFS_I(inode);
if (cifsInfo->time == 0)
return 1; /* directory was changed, perhaps due to unlink */
else
return 0;
}
static int cifs_save_resume_key(const char *current_entry,
struct cifsFileInfo *cifsFile)
{
int rc = 0;
unsigned int len = 0;
__u16 level;
char *filename;
if ((cifsFile == NULL) || (current_entry == NULL))
return -EINVAL;
level = cifsFile->srch_inf.info_level;
if (level == SMB_FIND_FILE_UNIX) {
FILE_UNIX_INFO *pFindData = (FILE_UNIX_INFO *)current_entry;
filename = &pFindData->FileName[0];
if (cifsFile->srch_inf.unicode) {
len = cifs_unicode_bytelen(filename);
} else {
/* BB should we make this strnlen of PATH_MAX? */
len = strnlen(filename, PATH_MAX);
}
cifsFile->srch_inf.resume_key = pFindData->ResumeKey;
} else if (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);
cifsFile->srch_inf.resume_key = pFindData->FileIndex;
} else if (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);
cifsFile->srch_inf.resume_key = pFindData->FileIndex;
} else if (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);
cifsFile->srch_inf.resume_key = pFindData->FileIndex;
} else if (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);
cifsFile->srch_inf.resume_key = pFindData->FileIndex;
} else if (level == SMB_FIND_FILE_INFO_STANDARD) {
FIND_FILE_STANDARD_INFO *pFindData =
(FIND_FILE_STANDARD_INFO *)current_entry;
filename = &pFindData->FileName[0];
/* one byte length, no name conversion */
len = (unsigned int)pFindData->FileNameLength;
cifsFile->srch_inf.resume_key = pFindData->ResumeKey;
} else {
cFYI(1, ("Unknown findfirst level %d", level));
return -EINVAL;
}
cifsFile->srch_inf.resume_name_len = len;
cifsFile->srch_inf.presume_name = filename;
return rc;
}
/* find the corresponding entry in the search */
/* Note that the SMB server returns search entries for . and .. which
complicates logic here if we choose to parse for them and we do not
assume that they are located in the findfirst return buffer.*/
/* We start counting in the buffer with entry 2 and increment for every
entry (do not increment for . or .. entry) */
static int find_cifs_entry(const int xid, struct cifsTconInfo *pTcon,
struct file *file, char **ppCurrentEntry, int *num_to_ret)
{
int rc = 0;
int pos_in_buf = 0;
loff_t first_entry_in_buffer;
loff_t index_to_find = file->f_pos;
struct cifsFileInfo *cifsFile = file->private_data;
/* check if index in the buffer */
if ((cifsFile == NULL) || (ppCurrentEntry == NULL) ||
(num_to_ret == NULL))
return -ENOENT;
*ppCurrentEntry = NULL;
first_entry_in_buffer =
cifsFile->srch_inf.index_of_last_entry -
cifsFile->srch_inf.entries_in_buffer;
/* if first entry in buf is zero then is first buffer
in search response data which means it is likely . and ..
will be in this buffer, although some servers do not return
. and .. for the root of a drive and for those we need
to start two entries earlier */
dump_cifs_file_struct(file, "In fce ");
if (((index_to_find < cifsFile->srch_inf.index_of_last_entry) &&
is_dir_changed(file)) ||
(index_to_find < first_entry_in_buffer)) {
/* close and restart search */
cFYI(1, ("search backing up - close and restart search"));
write_lock(&GlobalSMBSeslock);
if (!cifsFile->srch_inf.endOfSearch &&
!cifsFile->invalidHandle) {
cifsFile->invalidHandle = true;
write_unlock(&GlobalSMBSeslock);
CIFSFindClose(xid, pTcon, cifsFile->netfid);
} else
write_unlock(&GlobalSMBSeslock);
if (cifsFile->srch_inf.ntwrk_buf_start) {
cFYI(1, ("freeing SMB ff cache buf on search rewind"));
if (cifsFile->srch_inf.smallBuf)
cifs_small_buf_release(cifsFile->srch_inf.
ntwrk_buf_start);
else
cifs_buf_release(cifsFile->srch_inf.
ntwrk_buf_start);
cifsFile->srch_inf.ntwrk_buf_start = NULL;
}
rc = initiate_cifs_search(xid, file);
if (rc) {
cFYI(1, ("error %d reinitiating a search on rewind",
rc));
return rc;
}
cifs_save_resume_key(cifsFile->srch_inf.last_entry, cifsFile);
}
while ((index_to_find >= cifsFile->srch_inf.index_of_last_entry) &&
(rc == 0) && !cifsFile->srch_inf.endOfSearch) {
cFYI(1, ("calling findnext2"));
rc = CIFSFindNext(xid, pTcon, cifsFile->netfid,
&cifsFile->srch_inf);
cifs_save_resume_key(cifsFile->srch_inf.last_entry, cifsFile);
if (rc)
return -ENOENT;
}
if (index_to_find < cifsFile->srch_inf.index_of_last_entry) {
/* we found the buffer that contains the entry */
/* scan and find it */
int i;
char *current_entry;
char *end_of_smb = cifsFile->srch_inf.ntwrk_buf_start +
smbCalcSize((struct smb_hdr *)
cifsFile->srch_inf.ntwrk_buf_start);
current_entry = cifsFile->srch_inf.srch_entries_start;
first_entry_in_buffer = cifsFile->srch_inf.index_of_last_entry
- cifsFile->srch_inf.entries_in_buffer;
pos_in_buf = index_to_find - first_entry_in_buffer;
cFYI(1, ("found entry - pos_in_buf %d", pos_in_buf));
for (i = 0; (i < (pos_in_buf)) && (current_entry != NULL); i++) {
/* go entry by entry figuring out which is first */
current_entry = nxt_dir_entry(current_entry, end_of_smb,
cifsFile->srch_inf.info_level);
}
if ((current_entry == NULL) && (i < pos_in_buf)) {
/* BB fixme - check if we should flag this error */
cERROR(1, ("reached end of buf searching for pos in buf"
" %d index to find %lld rc %d",
pos_in_buf, index_to_find, rc));
}
rc = 0;
*ppCurrentEntry = current_entry;
} else {
cFYI(1, ("index not in buffer - could not findnext into it"));
return 0;
}
if (pos_in_buf >= cifsFile->srch_inf.entries_in_buffer) {
cFYI(1, ("can not return entries pos_in_buf beyond last"));
*num_to_ret = 0;
} else
*num_to_ret = cifsFile->srch_inf.entries_in_buffer - pos_in_buf;
return rc;
}
/* inode num, inode type and filename returned */
static int cifs_get_name_from_search_buf(struct qstr *pqst,
char *current_entry, __u16 level, unsigned int unicode,
struct cifs_sb_info *cifs_sb, int max_len, __u64 *pinum)
{
int rc = 0;
unsigned int len = 0;
char *filename;
struct nls_table *nlt = cifs_sb->local_nls;
*pinum = 0;
if (level == SMB_FIND_FILE_UNIX) {
FILE_UNIX_INFO *pFindData = (FILE_UNIX_INFO *)current_entry;
filename = &pFindData->FileName[0];
if (unicode) {
len = cifs_unicode_bytelen(filename);
} else {
/* BB should we make this strnlen of PATH_MAX? */
len = strnlen(filename, PATH_MAX);
}
*pinum = le64_to_cpu(pFindData->UniqueId);
} else if (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 (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 (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);
*pinum = le64_to_cpu(pFindData->UniqueId);
} else if (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 (level == SMB_FIND_FILE_INFO_STANDARD) {
FIND_FILE_STANDARD_INFO *pFindData =
(FIND_FILE_STANDARD_INFO *)current_entry;
filename = &pFindData->FileName[0];
/* one byte length, no name conversion */
len = (unsigned int)pFindData->FileNameLength;
} else {
cFYI(1, ("Unknown findfirst level %d", level));
return -EINVAL;
}
if (len > max_len) {
cERROR(1, ("bad search response length %d past smb end", len));
return -EINVAL;
}
if (unicode) {
/* BB fixme - test with long names */
/* Note converted filename can be longer than in unicode */
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR)
pqst->len = cifs_convertUCSpath((char *)pqst->name,
(__le16 *)filename, len/2, nlt);
else
pqst->len = cifs_strfromUCS_le((char *)pqst->name,
(__le16 *)filename, len/2, nlt);
} else {
pqst->name = filename;
pqst->len = len;
}
pqst->hash = full_name_hash(pqst->name, pqst->len);
/* cFYI(1, ("filldir on %s",pqst->name)); */
return rc;
}
static int cifs_filldir(char *pfindEntry, struct file *file,
filldir_t filldir, void *direntry, char *scratch_buf, int max_len)
{
int rc = 0;
struct qstr qstring;
struct cifsFileInfo *pCifsF;
unsigned int obj_type;
__u64 inum;
struct cifs_sb_info *cifs_sb;
struct inode *tmp_inode;
struct dentry *tmp_dentry;
/* get filename and len into qstring */
/* get dentry */
/* decide whether to create and populate ionde */
if ((direntry == NULL) || (file == NULL))
return -EINVAL;
pCifsF = file->private_data;
if ((scratch_buf == NULL) || (pfindEntry == NULL) || (pCifsF == NULL))
return -ENOENT;
rc = cifs_entry_is_dot(pfindEntry, pCifsF);
/* skip . and .. since we added them first */
if (rc != 0)
return 0;
cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
qstring.name = scratch_buf;
rc = cifs_get_name_from_search_buf(&qstring, pfindEntry,
pCifsF->srch_inf.info_level,
pCifsF->srch_inf.unicode, cifs_sb,
max_len,
&inum /* returned */);
if (rc)
return rc;
/* only these two infolevels return valid inode numbers */
if (pCifsF->srch_inf.info_level == SMB_FIND_FILE_UNIX ||
pCifsF->srch_inf.info_level == SMB_FIND_FILE_ID_FULL_DIR_INFO)
rc = construct_dentry(&qstring, file, &tmp_inode, &tmp_dentry,
&inum);
else
rc = construct_dentry(&qstring, file, &tmp_inode, &tmp_dentry,
NULL);
if ((tmp_inode == NULL) || (tmp_dentry == NULL))
return -ENOMEM;
/* we pass in rc below, indicating whether it is a new inode,
so we can figure out whether to invalidate the inode cached
data if the file has changed */
if (pCifsF->srch_inf.info_level == SMB_FIND_FILE_UNIX)
unix_fill_in_inode(tmp_inode,
(FILE_UNIX_INFO *)pfindEntry,
&obj_type, rc);
else if (pCifsF->srch_inf.info_level == SMB_FIND_FILE_INFO_STANDARD)
fill_in_inode(tmp_inode, 0 /* old level 1 buffer type */,
pfindEntry, &obj_type, rc);
else
fill_in_inode(tmp_inode, 1 /* NT */, pfindEntry, &obj_type, rc);
if (rc) /* new inode - needs to be tied to dentry */ {
d_instantiate(tmp_dentry, tmp_inode);
if (rc == 2)
d_rehash(tmp_dentry);
}
rc = filldir(direntry, qstring.name, qstring.len, file->f_pos,
tmp_inode->i_ino, obj_type);
if (rc) {
cFYI(1, ("filldir rc = %d", rc));
/* we can not return filldir errors to the caller
since they are "normal" when the stat blocksize
is too small - we return remapped error instead */
rc = -EOVERFLOW;
}
dput(tmp_dentry);
return rc;
}
int cifs_readdir(struct file *file, void *direntry, filldir_t filldir)
{
int rc = 0;
int xid, i;
struct cifs_sb_info *cifs_sb;
struct cifsTconInfo *pTcon;
struct cifsFileInfo *cifsFile = NULL;
char *current_entry;
int num_to_fill = 0;
char *tmp_buf = NULL;
char *end_of_smb;
int max_len;
xid = GetXid();
cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
pTcon = cifs_sb->tcon;
if (pTcon == NULL)
return -EINVAL;
switch ((int) file->f_pos) {
case 0:
if (filldir(direntry, ".", 1, file->f_pos,
file->f_path.dentry->d_inode->i_ino, DT_DIR) < 0) {
cERROR(1, ("Filldir for current dir failed"));
rc = -ENOMEM;
break;
}
file->f_pos++;
case 1:
if (filldir(direntry, "..", 2, file->f_pos,
file->f_path.dentry->d_parent->d_inode->i_ino, DT_DIR) < 0) {
cERROR(1, ("Filldir for parent dir failed"));
rc = -ENOMEM;
break;
}
file->f_pos++;
default:
/* 1) If search is active,
is in current search buffer?
if it before then restart search
if after then keep searching till find it */
if (file->private_data == NULL) {
rc = initiate_cifs_search(xid, file);
cFYI(1, ("initiate cifs search rc %d", rc));
if (rc) {
FreeXid(xid);
return rc;
}
}
if (file->private_data == NULL) {
rc = -EINVAL;
FreeXid(xid);
return rc;
}
cifsFile = file->private_data;
if (cifsFile->srch_inf.endOfSearch) {
if (cifsFile->srch_inf.emptyDir) {
cFYI(1, ("End of search, empty dir"));
rc = 0;
break;
}
} /* else {
cifsFile->invalidHandle = true;
CIFSFindClose(xid, pTcon, cifsFile->netfid);
} */
rc = find_cifs_entry(xid, pTcon, file,
&current_entry, &num_to_fill);
if (rc) {
cFYI(1, ("fce error %d", rc));
goto rddir2_exit;
} else if (current_entry != NULL) {
cFYI(1, ("entry %lld found", file->f_pos));
} else {
cFYI(1, ("could not find entry"));
goto rddir2_exit;
}
cFYI(1, ("loop through %d times filling dir for net buf %p",
num_to_fill, cifsFile->srch_inf.ntwrk_buf_start));
max_len = smbCalcSize((struct smb_hdr *)
cifsFile->srch_inf.ntwrk_buf_start);
end_of_smb = cifsFile->srch_inf.ntwrk_buf_start + max_len;
/* To be safe - for UCS to UTF-8 with strings loaded
with the rare long characters alloc more to account for
such multibyte target UTF-8 characters. cifs_unicode.c,
which actually does the conversion, has the same limit */
tmp_buf = kmalloc((2 * NAME_MAX) + 4, GFP_KERNEL);
for (i = 0; (i < num_to_fill) && (rc == 0); i++) {
if (current_entry == NULL) {
/* evaluate whether this case is an error */
cERROR(1, ("past SMB end, num to fill %d i %d",
num_to_fill, i));
break;
}
/* if buggy server returns . and .. late do
we want to check for that here? */
rc = cifs_filldir(current_entry, file,
filldir, direntry, tmp_buf, max_len);
if (rc == -EOVERFLOW) {
rc = 0;
break;
}
file->f_pos++;
if (file->f_pos ==
cifsFile->srch_inf.index_of_last_entry) {
cFYI(1, ("last entry in buf at pos %lld %s",
file->f_pos, tmp_buf));
cifs_save_resume_key(current_entry, cifsFile);
break;
} else
current_entry =
nxt_dir_entry(current_entry, end_of_smb,
cifsFile->srch_inf.info_level);
}
kfree(tmp_buf);
break;
} /* end switch */
rddir2_exit:
FreeXid(xid);
return rc;
}
Reference in New Issue View Git Blame Copy Permalink