54be1f6c1c
* Add new dfs_cache.[ch] files
* Add new /proc/fs/cifs/dfscache file
- dump current cache when read
- clear current cache when writing "0" to it
* Add delayed_work to periodically refresh cache entries
The new interface will be used for caching DFS referrals, as well as
supporting client target failover.
The DFS cache is a hashtable that maps UNC paths to cache entries.
A cache entry contains:
- the UNC path it is mapped on
- how much the the UNC path the entry consumes
- flags
- a Time-To-Live after which the entry expires
- a list of possible targets (linked lists of UNC paths)
- a "hint target" pointing the last known working target or the first
target if none were tried. This hint lets cifs.ko remember and try
working targets first.
* Looking for an entry in the cache is done with dfs_cache_find()
- if no valid entries are found, a DFS query is made, stored in the
cache and returned
- the full target list can be copied and returned to avoid race
conditions and looped on with the help with the
dfs_cache_tgt_iterator
* Updating the target hint to the next target is done with
dfs_cache_update_tgthint()
These functions have a dfs_cache_noreq_XXX() version that doesn't
fetches referrals if no entries are found. These versions don't
require the tcp/ses/tcon/cifs_sb parameters as a result.
Expired entries cannot be used and since they have a pretty short TTL
[1] in order for them to be useful for failover the DFS cache adds a
delayed work called periodically to keep them fresh.
Since we might not have available connections to issue the referral
request when refreshing we need to store volume_info structs with
credentials and other needed info to be able to connect to the right
server.
1: Windows defaults: 5mn for domain-based referrals, 30mn for regular
links
Signed-off-by: Paulo Alcantara <palcantara@suse.de>
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
25 lines
797 B
Makefile
25 lines
797 B
Makefile
# SPDX-License-Identifier: GPL-2.0
|
|
#
|
|
# Makefile for Linux CIFS/SMB2/SMB3 VFS client
|
|
#
|
|
ccflags-y += -I$(src) # needed for trace events
|
|
obj-$(CONFIG_CIFS) += cifs.o
|
|
|
|
cifs-y := trace.o cifsfs.o cifssmb.o cifs_debug.o connect.o dir.o file.o \
|
|
inode.o link.o misc.o netmisc.o smbencrypt.o transport.o asn1.o \
|
|
cifs_unicode.o nterr.o cifsencrypt.o \
|
|
readdir.o ioctl.o sess.o export.o smb1ops.o winucase.o \
|
|
smb2ops.o smb2maperror.o smb2transport.o \
|
|
smb2misc.o smb2pdu.o smb2inode.o smb2file.o
|
|
|
|
cifs-$(CONFIG_CIFS_XATTR) += xattr.o
|
|
cifs-$(CONFIG_CIFS_ACL) += cifsacl.o
|
|
|
|
cifs-$(CONFIG_CIFS_UPCALL) += cifs_spnego.o
|
|
|
|
cifs-$(CONFIG_CIFS_DFS_UPCALL) += dns_resolve.o cifs_dfs_ref.o dfs_cache.o
|
|
|
|
cifs-$(CONFIG_CIFS_FSCACHE) += fscache.o cache.o
|
|
|
|
cifs-$(CONFIG_CIFS_SMB_DIRECT) += smbdirect.o
|