4 files changed, 188 insertions, 7 deletions

diff --git a/Documentation/devices.txt b/Documentation/devices.txt
index 3c406acd4dfa..b369a8c46a73 100644
--- a/Documentation/devices.txt
+++ b/Documentation/devices.txt
@@ -1721,11 +1721,6 @@ Your cooperation is appreciated.
                 These devices support the same API as the generic SCSI
                 devices.
 
- 97 block       Packet writing for CD/DVD devices
-                  0 = /dev/pktcdvd0     First packet-writing module
-                  1 = /dev/pktcdvd1     Second packet-writing module
-                    ...
-
  98 char        Control and Measurement Device (comedi)
                   0 = /dev/comedi0      First comedi device
                   1 = /dev/comedi1      Second comedi device
diff --git a/Documentation/memory-barriers.txt b/Documentation/memory-barriers.txt
index 92f0056d928c..c61d8b876fdb 100644
--- a/Documentation/memory-barriers.txt
+++ b/Documentation/memory-barriers.txt
@@ -1031,7 +1031,7 @@ conflict on any particular lock.
 LOCKS VS MEMORY ACCESSES
 ------------------------
 
-Consider the following: the system has a pair of spinlocks (N) and (Q), and
+Consider the following: the system has a pair of spinlocks (M) and (Q), and
 three CPUs; then should the following sequence of events occur:
 
         CPU 1                           CPU 2
@@ -1678,7 +1678,7 @@ CPU's caches by some other cache event:
         smp_wmb();
         <A:modify v=2>  <C:busy>
                         <C:queue v=2>
-        p = &b;         q = p;
+        p = &v;         q = p;
                         <D:request p>
         <B:modify p=&v> <D:commit p=&v>
                         <D:read p>
diff --git a/Documentation/networking/operstates.txt b/Documentation/networking/operstates.txt
new file mode 100644
index 000000000000..4a21d9bb836b
--- /dev/null
+++ b/Documentation/networking/operstates.txt
@@ -0,0 +1,161 @@
+
+1. Introduction
+
+Linux distinguishes between administrative and operational state of an
+interface. Admininstrative state is the result of "ip link set dev
+<dev> up or down" and reflects whether the administrator wants to use
+the device for traffic.
+
+However, an interface is not usable just because the admin enabled it
+- ethernet requires to be plugged into the switch and, depending on
+a site's networking policy and configuration, an 802.1X authentication
+to be performed before user data can be transferred. Operational state
+shows the ability of an interface to transmit this user data.
+
+Thanks to 802.1X, userspace must be granted the possibility to
+influence operational state. To accommodate this, operational state is
+split into two parts: Two flags that can be set by the driver only, and
+a RFC2863 compatible state that is derived from these flags, a policy,
+and changeable from userspace under certain rules.
+
+
+2. Querying from userspace
+
+Both admin and operational state can be queried via the netlink
+operation RTM_GETLINK. It is also possible to subscribe to RTMGRP_LINK
+to be notified of updates. This is important for setting from userspace.
+
+These values contain interface state:
+
+ifinfomsg::if_flags & IFF_UP:
+ Interface is admin up
+ifinfomsg::if_flags & IFF_RUNNING:
+ Interface is in RFC2863 operational state UP or UNKNOWN. This is for
+ backward compatibility, routing daemons, dhcp clients can use this
+ flag to determine whether they should use the interface.
+ifinfomsg::if_flags & IFF_LOWER_UP:
+ Driver has signaled netif_carrier_on()
+ifinfomsg::if_flags & IFF_DORMANT:
+ Driver has signaled netif_dormant_on()
+
+These interface flags can also be queried without netlink using the
+SIOCGIFFLAGS ioctl.
+
+TLV IFLA_OPERSTATE
+
+contains RFC2863 state of the interface in numeric representation:
+
+IF_OPER_UNKNOWN (0):
+ Interface is in unknown state, neither driver nor userspace has set
+ operational state. Interface must be considered for user data as
+ setting operational state has not been implemented in every driver.
+IF_OPER_NOTPRESENT (1):
+ Unused in current kernel (notpresent interfaces normally disappear),
+ just a numerical placeholder.
+IF_OPER_DOWN (2):
+ Interface is unable to transfer data on L1, f.e. ethernet is not
+ plugged or interface is ADMIN down.
+IF_OPER_LOWERLAYERDOWN (3):
+ Interfaces stacked on an interface that is IF_OPER_DOWN show this
+ state (f.e. VLAN).
+IF_OPER_TESTING (4):
+ Unused in current kernel.
+IF_OPER_DORMANT (5):
+ Interface is L1 up, but waiting for an external event, f.e. for a
+ protocol to establish. (802.1X)
+IF_OPER_UP (6):
+ Interface is operational up and can be used.
+
+This TLV can also be queried via sysfs.
+
+TLV IFLA_LINKMODE
+
+contains link policy. This is needed for userspace interaction
+described below.
+
+This TLV can also be queried via sysfs.
+
+
+3. Kernel driver API
+
+Kernel drivers have access to two flags that map to IFF_LOWER_UP and
+IFF_DORMANT. These flags can be set from everywhere, even from
+interrupts. It is guaranteed that only the driver has write access,
+however, if different layers of the driver manipulate the same flag,
+the driver has to provide the synchronisation needed.
+
+__LINK_STATE_NOCARRIER, maps to !IFF_LOWER_UP:
+
+The driver uses netif_carrier_on() to clear and netif_carrier_off() to
+set this flag. On netif_carrier_off(), the scheduler stops sending
+packets. The name 'carrier' and the inversion are historical, think of
+it as lower layer.
+
+netif_carrier_ok() can be used to query that bit.
+
+__LINK_STATE_DORMANT, maps to IFF_DORMANT:
+
+Set by the driver to express that the device cannot yet be used
+because some driver controlled protocol establishment has to
+complete. Corresponding functions are netif_dormant_on() to set the
+flag, netif_dormant_off() to clear it and netif_dormant() to query.
+
+On device allocation, networking core sets the flags equivalent to
+netif_carrier_ok() and !netif_dormant().
+
+
+Whenever the driver CHANGES one of these flags, a workqueue event is
+scheduled to translate the flag combination to IFLA_OPERSTATE as
+follows:
+
+!netif_carrier_ok():
+ IF_OPER_LOWERLAYERDOWN if the interface is stacked, IF_OPER_DOWN
+ otherwise. Kernel can recognise stacked interfaces because their
+ ifindex != iflink.
+
+netif_carrier_ok() && netif_dormant():
+ IF_OPER_DORMANT
+
+netif_carrier_ok() && !netif_dormant():
+ IF_OPER_UP if userspace interaction is disabled. Otherwise
+ IF_OPER_DORMANT with the possibility for userspace to initiate the
+ IF_OPER_UP transition afterwards.
+
+
+4. Setting from userspace
+
+Applications have to use the netlink interface to influence the
+RFC2863 operational state of an interface. Setting IFLA_LINKMODE to 1
+via RTM_SETLINK instructs the kernel that an interface should go to
+IF_OPER_DORMANT instead of IF_OPER_UP when the combination
+netif_carrier_ok() && !netif_dormant() is set by the
+driver. Afterwards, the userspace application can set IFLA_OPERSTATE
+to IF_OPER_DORMANT or IF_OPER_UP as long as the driver does not set
+netif_carrier_off() or netif_dormant_on(). Changes made by userspace
+are multicasted on the netlink group RTMGRP_LINK.
+
+So basically a 802.1X supplicant interacts with the kernel like this:
+
+-subscribe to RTMGRP_LINK
+-set IFLA_LINKMODE to 1 via RTM_SETLINK
+-query RTM_GETLINK once to get initial state
+-if initial flags are not (IFF_LOWER_UP && !IFF_DORMANT), wait until
+ netlink multicast signals this state
+-do 802.1X, eventually abort if flags go down again
+-send RTM_SETLINK to set operstate to IF_OPER_UP if authentication
+ succeeds, IF_OPER_DORMANT otherwise
+-see how operstate and IFF_RUNNING is echoed via netlink multicast
+-set interface back to IF_OPER_DORMANT if 802.1X reauthentication
+ fails
+-restart if kernel changes IFF_LOWER_UP or IFF_DORMANT flag
+
+if supplicant goes down, bring back IFLA_LINKMODE to 0 and
+IFLA_OPERSTATE to a sane value.
+
+A routing daemon or dhcp client just needs to care for IFF_RUNNING or
+waiting for operstate to go IF_OPER_UP/IF_OPER_UNKNOWN before
+considering the interface / querying a DHCP address.
+
+
+For technical questions and/or comments please e-mail to Stefan Rompf
+(stefan at loplof.de).
diff --git a/Documentation/scsi/ChangeLog.megaraid b/Documentation/scsi/ChangeLog.megaraid
index 09f6300eda4b..c173806c91fa 100644
--- a/Documentation/scsi/ChangeLog.megaraid
+++ b/Documentation/scsi/ChangeLog.megaraid
@@ -1,3 +1,28 @@
+Release Date    : Mon Apr 11 12:27:22 EST 2006 - Seokmann Ju <sju@lsil.com>
+Current Version : 2.20.4.8 (scsi module), 2.20.2.6 (cmm module)
+Older Version   : 2.20.4.7 (scsi module), 2.20.2.6 (cmm module)
+
+1.      Fixed a bug in megaraid_reset_handler().
+        Customer reported "Unable to handle kernel NULL pointer dereference
+        at virtual address 00000000" when system goes to reset condition
+        for some reason. It happened randomly.
+        Root Cause: in the megaraid_reset_handler(), there is possibility not
+        returning pending packets in the pend_list if there are multiple
+        pending packets.
+        Fix: Made the change in the driver so that it will return all packets
+        in the pend_list.
+
+2.      Added change request.
+        As found in the following URL, rmb() only didn't help the
+        problem. I had to increase the loop counter to 0xFFFFFF. (6 F's)
+        http://marc.theaimsgroup.com/?l=linux-scsi&m=110971060502497&w=2
+
+        I attached a patch for your reference, too.
+        Could you check and get this fix in your driver?
+
+        Best Regards,
+        Jun'ichi Nomura
+
 Release Date    : Fri Nov 11 12:27:22 EST 2005 - Seokmann Ju <sju@lsil.com>
 Current Version : 2.20.4.7 (scsi module), 2.20.2.6 (cmm module)
 Older Version   : 2.20.4.6 (scsi module), 2.20.2.6 (cmm module)