scsi: fcoe: Make fcoe_bus_type const

Now that the driver core can properly handle constant struct bus_type, move
the fcoe_bus_type variable to be a constant structure as well, placing it
into read-only memory which can not be modified at runtime.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ricardo B. Marliere <ricardo@marliere.net>
Link: https://lore.kernel.org/r/20240203-bus_cleanup-scsi-v1-1-6f552fb24f71@marliere.net
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: fcoe: Fix unsigned comparison with zero in store_ctlr_mode()

ctlr->mode is of unsigned type, it is never less than zero.

Fix this by using an extra variable called 'res', to store return value
from sysfs_match_string() and assign that to ctlr->mode on the success
path.

Fixes: edc22a7c8688 ("scsi: fcoe: Use sysfs_match_string() over fcoe_parse_mode()")
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Link: https://lore.kernel.org/r/20240102085245.600570-1-harshit.m.mogalapalli@oracle.com
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: fcoe: Use sysfs_match_string() over fcoe_parse_mode()

Instead of copying @buf into a new buffer and carefully managing its
newline/null-terminating status, we can just use sysfs_match_string() as it
uses sysfs_streq() internally which handles newline/null-term:

| /**
| * sysfs_streq - return true if strings are equal, modulo trailing newline
| * @s1: one string
| * @s2: another string
| *
| * This routine returns true iff two strings are equal, treating both
| * NUL and newline-then-NUL as equivalent string terminations. It's
| * geared for use with sysfs input strings, which generally terminate
| * with newlines but are compared against values without newlines.
| */
| bool sysfs_streq(const char *s1, const char *s2)
| ...

Then entirely drop the now unused fcoe_parse_mode(), being careful to
change if condition from checking for FIP_CONN_TYPE_UNKNOWN to < 0 as
sysfs_match_string() can return -EINVAL. Also check explicitly if
ctlr->mode is equal to FIP_CONN_TYPE_UNKNOWN -- this is probably preferred
to "<=" as the behavior is more obvious while maintaining functionality.

To get the compiler not to complain, make fip_conn_type_names const char *
const. Perhaps, this should also be done for fcf_state_names.

This also removes an instance of strncpy() which helps [1].

Link: https://github.com/KSPP/linux/issues/90 [1]
Cc: <linux-hardening@vger.kernel.org>
Signed-off-by: Justin Stitt <justinstitt@google.com>
Link: https://lore.kernel.org/r/20231212-strncpy-drivers-scsi-fcoe-fcoe_sysfs-c-v2-1-1f2d6b2fc409@google.com
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

driver core: bus: mark the struct bus_type for sysfs callbacks as constant

struct bus_type should never be modified in a sysfs callback as there is
nothing in the structure to modify, and frankly, the structure is almost
never used in a sysfs callback, so mark it as constant to allow struct
bus_type to be moved to read-only memory.

Cc: "David S. Miller" <davem@davemloft.net>
Cc: "James E.J. Bottomley" <jejb@linux.ibm.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Alexandre Bounine <alex.bou9@gmail.com>
Cc: Alison Schofield <alison.schofield@intel.com>
Cc: Ben Widawsky <bwidawsk@kernel.org>
Cc: Dexuan Cui <decui@microsoft.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Harald Freudenberger <freude@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Hu Haowen <src.res@email.cn>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Laurentiu Tudor <laurentiu.tudor@nxp.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Stuart Yoder <stuyoder@gmail.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Yanteng Si <siyanteng@loongson.cn>
Acked-by: Ilya Dryomov <idryomov@gmail.com> # rbd
Acked-by: Ira Weiny <ira.weiny@intel.com> # cxl
Reviewed-by: Alex Shi <alexs@kernel.org>
Acked-by: Iwona Winiarska <iwona.winiarska@intel.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com> # pci
Acked-by: Wei Liu <wei.liu@kernel.org>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com> # scsi
Link: https://lore.kernel.org/r/20230313182918.1312597-23-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

scsi: fcoe: Fix possible name leak when device_register() fails

If device_register() returns an error, the name allocated by dev_set_name()
needs to be freed. As the comment of device_register() says, one should use
put_device() to give up the reference in the error path. Fix this by
calling put_device(), then the name can be freed in kobject_cleanup().

The 'fcf' is freed in fcoe_fcf_device_release(), so the kfree() in the
error path can be removed.

The 'ctlr' is freed in fcoe_ctlr_device_release(), so don't use the error
label, just return NULL after calling put_device().

Fixes: 9a74e884ee71 ("[SCSI] libfcoe: Add fcoe_sysfs")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20221112094310.3633291-1-yangyingliang@huawei.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: fcoe: Remove unneeded semicolon

A semicolon is not needed after a switch statement.

Link: https://lore.kernel.org/r/20201101144017.2284047-1-trix@redhat.com
Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: fcoe: Simplify the return expression of fcoe_sysfs_setup()

Simplify the return expression.

Link: https://lore.kernel.org/r/20200921131102.93084-1-miaoqinglang@huawei.com
Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 335

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms and conditions of the gnu general public license
version 2 as published by the free software foundation this program
is distributed in the hope it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
for more details you should have received a copy of the gnu general
public license along with this program if not write to the free
software foundation inc 51 franklin st fifth floor boston ma 02110
1301 usa

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 111 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190530000436.567572064@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

scsi: libfcoe: switch to SPDX tags

Use the the GPLv2 SPDX tag instead of verbose boilerplate text.

[mkp: fixed comment syntax on *.c]

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: fcoe: convert to use BUS_ATTR_WO

We are trying to get rid of BUS_ATTR() and the usage of that in the fcoe
driver can be trivially converted to use BUS_ATTR_WO(), so use that
instead.

Cc: Johannes Thumshirn <jth@kernel.org>
Cc: "James E.J. Bottomley" <jejb@linux.vnet.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: make device_type const

Make these const as they are only stored in the type field of a device
structure, which is const.
Done using Coccinelle.

Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: fcoe: catch invalid values for the 'enabled' attribute

The 'enabled' sysfs attribute only accepts the values '0' and '1',
so we should error out any other values.

Signed-off-by: Hannes Reinecke <hare@suse.com>
Acked-by: Johannes Thumshirn <jth@kernel.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: fcoe: make R_A_TOV and E_D_TOV configurable

The user might want to modify the values for R_A_TOV and E_D_TOV,
so add new module parameters 'e_d_tov' and 'r_a_tov' for the
'fcoe' modules and allow to modify them via sysfs attributes.

Signed-off-by: Hannes Reinecke <hare@suse.com>
Acked-by: Johannes Thumshirn <jth@kernel.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

fcoe: implement FIP VLAN responder

When running in VN2VN mode there is no central instance which would send
out any FIP VLAN discovery notifications. So this patch adds a new sysfs
attribute 'fip_vlan_responder' which will activate a FIP VLAN discovery
responder.

Signed-off-by: Hannes Reinecke <hare@suse.com>
Acked-by: Johannes Thumshirn <jth@kernel.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: Convert uses of compare_ether_addr to ether_addr_equal

Preliminary to removing compare_ether_addr altogether:

Use the new bool function ether_addr_equal to add
some clarity and reduce the likelihood for misuse
of compare_ether_addr for sorting.

Done via cocci script:

$ cat compare_ether_addr.cocci
@@
expression a,b;
@@
- !compare_ether_addr(a, b)
+ ether_addr_equal(a, b)

@@
expression a,b;
@@
- compare_ether_addr(a, b)
+ !ether_addr_equal(a, b)

@@
expression a,b;
@@
- !ether_addr_equal(a, b) == 0
+ ether_addr_equal(a, b)

@@
expression a,b;
@@
- !ether_addr_equal(a, b) != 0
+ !ether_addr_equal(a, b)

@@
expression a,b;
@@
- ether_addr_equal(a, b) == 0
+ !ether_addr_equal(a, b)

@@
expression a,b;
@@
- ether_addr_equal(a, b) != 0
+ ether_addr_equal(a, b)

@@
expression a,b;
@@
- !!ether_addr_equal(a, b)
+ ether_addr_equal(a, b)

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>

scsi: fcoe: fix build error

I had a typo in a variable name for the previous patch (SCSI: fcoe:
convert bus code to use bus_group) that broke the build, this fixes
that.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

SCSI: fcoe: convert bus code to use bus_groups

The bus_attrs field of struct bus_type is going away soon, dev_groups
should be used instead. This converts the fcoe bus code to use the
correct field.

Cc: Robert Love <robert.w.love@intel.com>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

fcoe: Add missing newlines in debug messages

FCoE debug statements must end in a newline. Add one where it is missing.

Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Cc: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>

fcoe: Reduce number of sparse warnings

Declare local variables and functions 'static'. This patch does not
change any functionality.

Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Robert Love <robert.w.love@intel.com>

libfcoe, fcoe, bnx2fc: Add new fcoe control interface

This patch does a few things.

1) Makes /sys/bus/fcoe/ctlr_{create,destroy} interfaces.
These interfaces take an <ifname> and will either
create an FCoE Controller or destroy an FCoE
Controller depending on which file is written to.

The new FCoE Controller will start in a DISABLED
state and will not do discovery or login until it
is ENABLED. This pause will allow us to configure
the FCoE Controller before enabling it.

2) Makes the 'mode' attribute of a fcoe_ctlr_device
writale. This allows the user to configure the mode
in which the FCoE Controller will start in when it
is ENABLED.

Possible modes are 'Fabric', or 'VN2VN'.

The default mode for a fcoe_ctlr{,_device} is 'Fabric'.
Drivers must implement the set_fcoe_ctlr_mode routine
to support this feature.

libfcoe offers an exported routine to set a FCoE
Controller's mode. The mode can only be changed
when the FCoE Controller is DISABLED.

This patch also removes the get_fcoe_ctlr_mode pointer
in the fcoe_sysfs function template, the code in
fcoe_ctlr.c to get the mode and the assignment of
the fcoe_sysfs function pointer to the fcoe_ctlr.c
implementation (in fcoe and bnx2fc). fcoe_sysfs can
return that value for the mode without consulting the
LLD.

3) Make a 'enabled' attribute of a fcoe_ctlr_device. On a
read, fcoe_sysfs will return the attribute's value. On
a write, fcoe_sysfs will call the LLD (if there is a
callback) to notifiy that the enalbed state has changed.

This patch maintains the old FCoE control interfaces as
module parameters, but it adds comments pointing out that
the old interfaces are deprecated.

Signed-off-by: Robert Love <robert.w.love@intel.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>

libfcoe: Add fcoe_sysfs debug logging level

Add a macro to print fcoe_sysfs debug statements.

Signed-off-by: Robert Love <robert.w.love@intel.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>

libfcoe: Save some memory and optimize name lookups

Instead of creating a structure with an enum and a pointer
to a string, simply allocate an array of strings and use
the enum values for the indicies.

This means that we do not need to iterate through the list
of entries when looking up a string name by its enum key.

This will also help with a latter patch that will add
more fcoe_sysfs attributes that will also use the
fcoe_enum_name_search macro. One attribute will also do
a reverse lookup which requires less code when the
enum-to-string mappings are organized as this patch makes
them to be.

Signed-off-by: Robert Love <robert.w.love@intel.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>

[SCSI] fcoe: Remove redundant 'less than zero' check

strtoul returns an 'unsigned long' so there is no
reason to check if the value is less than zero.

strtoul already checks for the '-' character deep
in its bowels. It will return an error if the user
has provided a negative value and fcoe_str_to_dev_loss
will return that error to its caller.

This patch fixes the following Coverity reported warning:

CID 703581 - NO_EFFECT Unsigned compared against 0 - This
less-than-zero comparison of an unsigned value is never true. "*val < 0UL".
drivers/scsi/fcoe/fcoe_sysfs.c:105

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

[SCSI] libfcoe: Add fcoe_sysfs

This patch adds a 'fcoe bus' infrastructure to the kernel
that is driven by changes to libfcoe which allow LLDs to
present FIP (FCoE Initialization Protocol) discovered
entities and their attributes to user space via sysfs.

This patch adds the following APIs-

fcoe_ctlr_device_add
fcoe_ctlr_device_delete
fcoe_fcf_device_add
fcoe_fcf_device_delete

They allow the LLD to expose the FCoE ENode Controller
and any discovered FCFs (Fibre Channel Forwarders, e.g.
FCoE switches) to the user. Each of these new devices
has their own bus_type so that they are grouped together
for easy lookup from a user space application. Each
new class has an attribute_group to expose attributes
for any created instances. The attributes are-

fcoe_ctlr_device
* fcf_dev_loss_tmo
* lesb_link_fail
* lesb_vlink_fail
* lesb_miss_fka
* lesb_symb_err
* lesb_err_block
* lesb_fcs_error

fcoe_fcf_device
* fabric_name
* switch_name
* priority
* selected
* fc_map
* vfid
* mac
* fka_peroid
* fabric_state
* dev_loss_tmo

A device loss infrastructre similar to the FC Transport's
is also added by this patch. It is nice to have so that a
link flapping adapter doesn't continually advance the count
used to identify the discovered FCF. FCFs will exist in a
"Disconnected" state until either the timer expires or the
FCF is rediscovered and becomes "Connected."

This patch generates a few checkpatch.pl WARNINGS that
I'm not sure what to do about. They're macros modeled
around the FC Transport attribute building macros, which
have the same 'feature' where the caller can ommit a cast
in the argument list and no cast occurs in the code. I'm
not sure how to keep the code condensed while keeping the
macros. Any advice would be appreciated.

Signed-off-by: Robert Love <robert.w.love@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>