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Add an interface to the AF_RXRPC module so that the AFS filesystem module can more easily make use of the services available. AFS still opens a socket but then uses the action functions in lieu of sendmsg() and registers an intercept functions to grab messages before they're queued on the socket Rx queue. This permits AFS (or whatever) to: (1) Avoid the overhead of using the recvmsg() call. (2) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (3) Avoid calling request_key() at the point of issue of a call or opening of a socket. This is done instead by AFS at the point of open(), unlink() or other VFS operation and the key handed through. (4) Request the use of something other than GFP_KERNEL to allocate memory. Furthermore: (*) The socket buffer markings used by RxRPC are made available for AFS so that it can interpret the cooked RxRPC messages itself. (*) rxgen (un)marshalling abort codes are made available. The following documentation for the kernel interface is added to Documentation/networking/rxrpc.txt: ========================= AF_RXRPC KERNEL INTERFACE ========================= The AF_RXRPC module also provides an interface for use by in-kernel utilities such as the AFS filesystem. This permits such a utility to: (1) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (2) Avoid having RxRPC call request_key() at the point of issue of a call or opening of a socket. Instead the utility is responsible for requesting a key at the appropriate point. AFS, for instance, would do this during VFS operations such as open() or unlink(). The key is then handed through when the call is initiated. (3) Request the use of something other than GFP_KERNEL to allocate memory. (4) Avoid the overhead of using the recvmsg() call. RxRPC messages can be intercepted before they get put into the socket Rx queue and the socket buffers manipulated directly. To use the RxRPC facility, a kernel utility must still open an AF_RXRPC socket, bind an addess as appropriate and listen if it's to be a server socket, but then it passes this to the kernel interface functions. The kernel interface functions are as follows: (*) Begin a new client call. struct rxrpc_call * rxrpc_kernel_begin_call(struct socket *sock, struct sockaddr_rxrpc *srx, struct key *key, unsigned long user_call_ID, gfp_t gfp); This allocates the infrastructure to make a new RxRPC call and assigns call and connection numbers. The call will be made on the UDP port that the socket is bound to. The call will go to the destination address of a connected client socket unless an alternative is supplied (srx is non-NULL). If a key is supplied then this will be used to secure the call instead of the key bound to the socket with the RXRPC_SECURITY_KEY sockopt. Calls secured in this way will still share connections if at all possible. The user_call_ID is equivalent to that supplied to sendmsg() in the control data buffer. It is entirely feasible to use this to point to a kernel data structure. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) End a client call. void rxrpc_kernel_end_call(struct rxrpc_call *call); This is used to end a previously begun call. The user_call_ID is expunged from AF_RXRPC's knowledge and will not be seen again in association with the specified call. (*) Send data through a call. int rxrpc_kernel_send_data(struct rxrpc_call *call, struct msghdr *msg, size_t len); This is used to supply either the request part of a client call or the reply part of a server call. msg.msg_iovlen and msg.msg_iov specify the data buffers to be used. msg_iov may not be NULL and must point exclusively to in-kernel virtual addresses. msg.msg_flags may be given MSG_MORE if there will be subsequent data sends for this call. The msg must not specify a destination address, control data or any flags other than MSG_MORE. len is the total amount of data to transmit. (*) Abort a call. void rxrpc_kernel_abort_call(struct rxrpc_call *call, u32 abort_code); This is used to abort a call if it's still in an abortable state. The abort code specified will be placed in the ABORT message sent. (*) Intercept received RxRPC messages. typedef void (*rxrpc_interceptor_t)(struct sock *sk, unsigned long user_call_ID, struct sk_buff *skb); void rxrpc_kernel_intercept_rx_messages(struct socket *sock, rxrpc_interceptor_t interceptor); This installs an interceptor function on the specified AF_RXRPC socket. All messages that would otherwise wind up in the socket's Rx queue are then diverted to this function. Note that care must be taken to process the messages in the right order to maintain DATA message sequentiality. The interceptor function itself is provided with the address of the socket and handling the incoming message, the ID assigned by the kernel utility to the call and the socket buffer containing the message. The skb->mark field indicates the type of message: MARK MEANING =============================== ======================================= RXRPC_SKB_MARK_DATA Data message RXRPC_SKB_MARK_FINAL_ACK Final ACK received for an incoming call RXRPC_SKB_MARK_BUSY Client call rejected as server busy RXRPC_SKB_MARK_REMOTE_ABORT Call aborted by peer RXRPC_SKB_MARK_NET_ERROR Network error detected RXRPC_SKB_MARK_LOCAL_ERROR Local error encountered RXRPC_SKB_MARK_NEW_CALL New incoming call awaiting acceptance The remote abort message can be probed with rxrpc_kernel_get_abort_code(). The two error messages can be probed with rxrpc_kernel_get_error_number(). A new call can be accepted with rxrpc_kernel_accept_call(). Data messages can have their contents extracted with the usual bunch of socket buffer manipulation functions. A data message can be determined to be the last one in a sequence with rxrpc_kernel_is_data_last(). When a data message has been used up, rxrpc_kernel_data_delivered() should be called on it.. Non-data messages should be handled to rxrpc_kernel_free_skb() to dispose of. It is possible to get extra refs on all types of message for later freeing, but this may pin the state of a call until the message is finally freed. (*) Accept an incoming call. struct rxrpc_call * rxrpc_kernel_accept_call(struct socket *sock, unsigned long user_call_ID); This is used to accept an incoming call and to assign it a call ID. This function is similar to rxrpc_kernel_begin_call() and calls accepted must be ended in the same way. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) Reject an incoming call. int rxrpc_kernel_reject_call(struct socket *sock); This is used to reject the first incoming call on the socket's queue with a BUSY message. -ENODATA is returned if there were no incoming calls. Other errors may be returned if the call had been aborted (-ECONNABORTED) or had timed out (-ETIME). (*) Record the delivery of a data message and free it. void rxrpc_kernel_data_delivered(struct sk_buff *skb); This is used to record a data message as having been delivered and to update the ACK state for the call. The socket buffer will be freed. (*) Free a message. void rxrpc_kernel_free_skb(struct sk_buff *skb); This is used to free a non-DATA socket buffer intercepted from an AF_RXRPC socket. (*) Determine if a data message is the last one on a call. bool rxrpc_kernel_is_data_last(struct sk_buff *skb); This is used to determine if a socket buffer holds the last data message to be received for a call (true will be returned if it does, false if not). The data message will be part of the reply on a client call and the request on an incoming call. In the latter case there will be more messages, but in the former case there will not. (*) Get the abort code from an abort message. u32 rxrpc_kernel_get_abort_code(struct sk_buff *skb); This is used to extract the abort code from a remote abort message. (*) Get the error number from a local or network error message. int rxrpc_kernel_get_error_number(struct sk_buff *skb); This is used to extract the error number from a message indicating either a local error occurred or a network error occurred. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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.. | ||
3c359.txt | ||
3c505.txt | ||
3c509.txt | ||
6pack.txt | ||
00-INDEX | ||
alias.txt | ||
arcnet-hardware.txt | ||
arcnet.txt | ||
atm.txt | ||
ax25.txt | ||
baycom.txt | ||
bcm43xx.txt | ||
bonding.txt | ||
bridge.txt | ||
comx.txt | ||
Configurable | ||
cops.txt | ||
cs89x0.txt | ||
cxgb.txt | ||
dccp.txt | ||
de4x5.txt | ||
decnet.txt | ||
depca.txt | ||
dgrs.txt | ||
dl2k.txt | ||
DLINK.txt | ||
dmfe.txt | ||
driver.txt | ||
e100.txt | ||
e1000.txt | ||
eql.txt | ||
ewrk3.txt | ||
fib_trie.txt | ||
filter.txt | ||
fore200e.txt | ||
framerelay.txt | ||
gen_stats.txt | ||
generic_netlink.txt | ||
generic-hdlc.txt | ||
gianfar.txt | ||
ifenslave.c | ||
ip_dynaddr.txt | ||
ip-sysctl.txt | ||
ipddp.txt | ||
iphase.txt | ||
ipvs-sysctl.txt | ||
irda.txt | ||
ixgb.txt | ||
lapb-module.txt | ||
LICENSE.qla3xxx | ||
ltpc.txt | ||
multicast.txt | ||
NAPI_HOWTO.txt | ||
ncsa-telnet | ||
net-modules.txt | ||
netconsole.txt | ||
netdevices.txt | ||
netif-msg.txt | ||
olympic.txt | ||
operstates.txt | ||
packet_mmap.txt | ||
phy.txt | ||
pktgen.txt | ||
PLIP.txt | ||
policy-routing.txt | ||
ppp_generic.txt | ||
proc_net_tcp.txt | ||
pt.txt | ||
ray_cs.txt | ||
README.ipw2100 | ||
README.ipw2200 | ||
README.sb1000 | ||
routing.txt | ||
rxrpc.txt | ||
s2io.txt | ||
sctp.txt | ||
secid.txt | ||
shaper.txt | ||
sk98lin.txt | ||
skfp.txt | ||
slicecom.hun | ||
slicecom.txt | ||
smc9.txt | ||
smctr.txt | ||
tcp.txt | ||
tlan.txt | ||
tms380tr.txt | ||
tuntap.txt | ||
udplite.txt | ||
vortex.txt | ||
wan-router.txt | ||
wavelan.txt | ||
x25-iface.txt | ||
x25.txt | ||
xfrm_sync.txt | ||
z8530drv.txt |
sb1000 is a module network device driver for the General Instrument (also known as NextLevel) SURFboard1000 internal cable modem board. This is an ISA card which is used by a number of cable TV companies to provide cable modem access. It's a one-way downstream-only cable modem, meaning that your upstream net link is provided by your regular phone modem. This driver was written by Franco Venturi <fventuri@mediaone.net>. He deserves a great deal of thanks for this wonderful piece of code! ----------------------------------------------------------------------------- Support for this device is now a part of the standard Linux kernel. The driver source code file is drivers/net/sb1000.c. In addition to this you will need: 1.) The "cmconfig" program. This is a utility which supplements "ifconfig" to configure the cable modem and network interface (usually called "cm0"); and 2.) Several PPP scripts which live in /etc/ppp to make connecting via your cable modem easy. These utilities can be obtained from: http://www.jacksonville.net/~fventuri/ in Franco's original source code distribution .tar.gz file. Support for the sb1000 driver can be found at: http://home.adelphia.net/~siglercm/sb1000.html http://linuxpower.cx/~cable/ along with these utilities. 3.) The standard isapnp tools. These are necessary to configure your SB1000 card at boot time (or afterwards by hand) since it's a PnP card. If you don't have these installed as a standard part of your Linux distribution, you can find them at: http://www.roestock.demon.co.uk/isapnptools/ or check your Linux distribution binary CD or their web site. For help with isapnp, pnpdump, or /etc/isapnp.conf, go to: http://www.roestock.demon.co.uk/isapnptools/isapnpfaq.html ----------------------------------------------------------------------------- To make the SB1000 card work, follow these steps: 1.) Run `make config', or `make menuconfig', or `make xconfig', whichever you prefer, in the top kernel tree directory to set up your kernel configuration. Make sure to say "Y" to "Prompt for development drivers" and to say "M" to the sb1000 driver. Also say "Y" or "M" to all the standard networking questions to get TCP/IP and PPP networking support. 2.) *BEFORE* you build the kernel, edit drivers/net/sb1000.c. Make sure to redefine the value of READ_DATA_PORT to match the I/O address used by isapnp to access your PnP cards. This is the value of READPORT in /etc/isapnp.conf or given by the output of pnpdump. 3.) Build and install the kernel and modules as usual. 4.) Boot your new kernel following the usual procedures. 5.) Set up to configure the new SB1000 PnP card by capturing the output of "pnpdump" to a file and editing this file to set the correct I/O ports, IRQ, and DMA settings for all your PnP cards. Make sure none of the settings conflict with one another. Then test this configuration by running the "isapnp" command with your new config file as the input. Check for errors and fix as necessary. (As an aside, I use I/O ports 0x110 and 0x310 and IRQ 11 for my SB1000 card and these work well for me. YMMV.) Then save the finished config file as /etc/isapnp.conf for proper configuration on subsequent reboots. 6.) Download the original file sb1000-1.1.2.tar.gz from Franco's site or one of the others referenced above. As root, unpack it into a temporary directory and do a `make cmconfig' and then `install -c cmconfig /usr/local/sbin'. Don't do `make install' because it expects to find all the utilities built and ready for installation, not just cmconfig. 7.) As root, copy all the files under the ppp/ subdirectory in Franco's tar file into /etc/ppp, being careful not to overwrite any files that are already in there. Then modify ppp@gi-on to set the correct login name, phone number, and frequency for the cable modem. Also edit pap-secrets to specify your login name and password and any site-specific information you need. 8.) Be sure to modify /etc/ppp/firewall to use ipchains instead of the older ipfwadm commands from the 2.0.x kernels. There's a neat utility to convert ipfwadm commands to ipchains commands: http://users.dhp.com/~whisper/ipfwadm2ipchains/ You may also wish to modify the firewall script to implement a different firewalling scheme. 9.) Start the PPP connection via the script /etc/ppp/ppp@gi-on. You must be root to do this. It's better to use a utility like sudo to execute frequently used commands like this with root permissions if possible. If you connect successfully the cable modem interface will come up and you'll see a driver message like this at the console: cm0: sb1000 at (0x110,0x310), csn 1, S/N 0x2a0d16d8, IRQ 11. sb1000.c:v1.1.2 6/01/98 (fventuri@mediaone.net) The "ifconfig" command should show two new interfaces, ppp0 and cm0. The command "cmconfig cm0" will give you information about the cable modem interface. 10.) Try pinging a site via `ping -c 5 www.yahoo.com', for example. You should see packets received. 11.) If you can't get site names (like www.yahoo.com) to resolve into IP addresses (like 204.71.200.67), be sure your /etc/resolv.conf file has no syntax errors and has the right nameserver IP addresses in it. If this doesn't help, try something like `ping -c 5 204.71.200.67' to see if the networking is running but the DNS resolution is where the problem lies. 12.) If you still have problems, go to the support web sites mentioned above and read the information and documentation there. ----------------------------------------------------------------------------- Common problems: 1.) Packets go out on the ppp0 interface but don't come back on the cm0 interface. It looks like I'm connected but I can't even ping any numerical IP addresses. (This happens predominantly on Debian systems due to a default boot-time configuration script.) Solution -- As root `echo 0 > /proc/sys/net/ipv4/conf/cm0/rp_filter' so it can share the same IP address as the ppp0 interface. Note that this command should probably be added to the /etc/ppp/cablemodem script *right*between* the "/sbin/ifconfig" and "/sbin/cmconfig" commands. You may need to do this to /proc/sys/net/ipv4/conf/ppp0/rp_filter as well. If you do this to /proc/sys/net/ipv4/conf/default/rp_filter on each reboot (in rc.local or some such) then any interfaces can share the same IP addresses. 2.) I get "unresolved symbol" error messages on executing `insmod sb1000.o'. Solution -- You probably have a non-matching kernel source tree and /usr/include/linux and /usr/include/asm header files. Make sure you install the correct versions of the header files in these two directories. Then rebuild and reinstall the kernel. 3.) When isapnp runs it reports an error, and my SB1000 card isn't working. Solution -- There's a problem with later versions of isapnp using the "(CHECK)" option in the lines that allocate the two I/O addresses for the SB1000 card. This first popped up on RH 6.0. Delete "(CHECK)" for the SB1000 I/O addresses. Make sure they don't conflict with any other pieces of hardware first! Then rerun isapnp and go from there. 4.) I can't execute the /etc/ppp/ppp@gi-on file. Solution -- As root do `chmod ug+x /etc/ppp/ppp@gi-on'. 5.) The firewall script isn't working (with 2.2.x and higher kernels). Solution -- Use the ipfwadm2ipchains script referenced above to convert the /etc/ppp/firewall script from the deprecated ipfwadm commands to ipchains. 6.) I'm getting *tons* of firewall deny messages in the /var/kern.log, /var/messages, and/or /var/syslog files, and they're filling up my /var partition!!! Solution -- First, tell your ISP that you're receiving DoS (Denial of Service) and/or portscanning (UDP connection attempts) attacks! Look over the deny messages to figure out what the attack is and where it's coming from. Next, edit /etc/ppp/cablemodem and make sure the ",nobroadcast" option is turned on to the "cmconfig" command (uncomment that line). If you're not receiving these denied packets on your broadcast interface (IP address xxx.yyy.zzz.255 typically), then someone is attacking your machine in particular. Be careful out there.... 7.) Everything seems to work fine but my computer locks up after a while (and typically during a lengthy download through the cable modem)! Solution -- You may need to add a short delay in the driver to 'slow down' the SURFboard because your PC might not be able to keep up with the transfer rate of the SB1000. To do this, it's probably best to download Franco's sb1000-1.1.2.tar.gz archive and build and install sb1000.o manually. You'll want to edit the 'Makefile' and look for the 'SB1000_DELAY' define. Uncomment those 'CFLAGS' lines (and comment out the default ones) and try setting the delay to something like 60 microseconds with: '-DSB1000_DELAY=60'. Then do `make' and as root `make install' and try it out. If it still doesn't work or you like playing with the driver, you may try other numbers. Remember though that the higher the delay, the slower the driver (which slows down the rest of the PC too when it is actively used). Thanks to Ed Daiga for this tip! ----------------------------------------------------------------------------- Credits: This README came from Franco Venturi's original README file which is still supplied with his driver .tar.gz archive. I and all other sb1000 users owe Franco a tremendous "Thank you!" Additional thanks goes to Carl Patten and Ralph Bonnell who are now managing the Linux SB1000 web site, and to the SB1000 users who reported and helped debug the common problems listed above. Clemmitt Sigler csigler@vt.edu