It isn't clear if this function of_node_put()s the 'from'
argument, or the node it searches. Clearly indicate which
variable is touched. Fold in some more fixes from Randy too
because we're in the area.

Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Acked-by: NRandy Dunlap <rdunlap@infradead.org>
Signed-off-by: NRob Herring <robh@kernel.org>

The workaround code is never used because Skylake NTB does not need it.
Reported-by: NAllen Hubbe <allen.hubbe@dell.com>
Signed-off-by: NDave Jiang <dave.jiang@intel.com>
Signed-off-by: NJon Mason <jdmason@kudzu.us>

Make these const as they are only used during a copy operation.
Done using Coccinelle.
Signed-off-by: NBhumika Goyal <bhumirks@gmail.com>
Signed-off-by: NJon Mason <jdmason@kudzu.us>

The Switchtec hardware has two types of memory windows: LUTs and Direct.
The first area in each BAR is for LUT windows and the remaining area is
for the direct region. The total number of LUT entries is set by a
configuration setting in hardware and they all must be the same
size. (This is fixed by switchtec_ntb to be 64K.)

switchtec_ntb enables the LUTs only for the first BAR and enables the
highest power of two possible. Seeing the LUTs are at the beginning of
the BAR, the direct memory window's alignment is affected. Therefore,
the maximum direct memory window size can not be greater than the number
of LUTs times 64K. The direct window in other BARs will not have this
restriction as the LUTs will not be enabled there. LUTs will only be
exposed through the NTB API if the use_lut_mw parameter is set.

Seeing the Switchtec hardware, by default, configures BARs to be 4G a
module parameter is given to limit the size of the advertised memory
windows. Higher layers tend to allocate the maximum BAR size and this
has a tendency to fail when they try to allocate 4GB of contiguous
memory.
Signed-off-by: NLogan Gunthorpe <logang@deltatee.com>
Reviewed-by: NStephen Bates <sbates@raithlin.com>
Reviewed-by: NKurt Schwemmer <kurt.schwemmer@microsemi.com>
Acked-by: NAllen Hubbe <Allen.Hubbe@dell.com>
Signed-off-by: NJon Mason <jdmason@kudzu.us>

Seeing there is no dedicated hardware for this, we simply add
these as entries in the shared memory window. Thus, we could support
any number of them but 128 seems like enough, for now.
Signed-off-by: NLogan Gunthorpe <logang@deltatee.com>
Reviewed-by: NStephen Bates <sbates@raithlin.com>
Reviewed-by: NKurt Schwemmer <kurt.schwemmer@microsemi.com>
Acked-by: NAllen Hubbe <Allen.Hubbe@dell.com>
Signed-off-by: NJon Mason <jdmason@kudzu.us>

Pretty straightforward implementation of doorbell registers.
The shift and mask were setup in an earlier patch and this just hooks
up the appropriate portion of the IDB register as the local doorbells
and the opposite portion of ODB as the peer doorbells. The DB mask is
protected by a spinlock to avoid concurrent read-modify-write accesses.
Signed-off-by: NLogan Gunthorpe <logang@deltatee.com>
Reviewed-by: NStephen Bates <sbates@raithlin.com>
Reviewed-by: NKurt Schwemmer <kurt.schwemmer@microsemi.com>
Acked-by: NAllen Hubbe <Allen.Hubbe@dell.com>
Signed-off-by: NJon Mason <jdmason@kudzu.us>

switchtec_ntb checks for a link by looking at the shared memory
window. If the magic number is correct and the other side indicates
their link is enabled then we take the link to be up.

Whenever we change our local link status we send a msg to the
other side to check whether it's up and change their status.

The current status is maintained in a flag so ntb_is_link_up
can return quickly.

We utilize Switchtec's link status notifier to also check link changes
when the switch notices a port changes state.
Signed-off-by: NLogan Gunthorpe <logang@deltatee.com>
Reviewed-by: NStephen Bates <sbates@raithlin.com>
Reviewed-by: NKurt Schwemmer <kurt.schwemmer@microsemi.com>
Acked-by: NAllen Hubbe <Allen.Hubbe@dell.com>
Signed-off-by: NJon Mason <jdmason@kudzu.us>

Add a skeleton NTB driver which will be filled out in subsequent patches.
Signed-off-by: NLogan Gunthorpe <logang@deltatee.com>
Reviewed-by: NStephen Bates <sbates@raithlin.com>
Reviewed-by: NKurt Schwemmer <kurt.schwemmer@microsemi.com>
Acked-by: NAllen Hubbe <Allen.Hubbe@dell.com>
Signed-off-by: NJon Mason <jdmason@kudzu.us>

Set up some hardware registers and creates interrupt service routines
for the doorbells and messages.

There are 64 doorbells in the switch that are shared between all
partitions. The upper 4 doorbells are also shared with the messages
and are therefore not used. Thus, this provides 28 doorbells for each
partition.
Signed-off-by: NLogan Gunthorpe <logang@deltatee.com>
Reviewed-by: NStephen Bates <sbates@raithlin.com>
Reviewed-by: NKurt Schwemmer <kurt.schwemmer@microsemi.com>
Acked-by: NAllen Hubbe <Allen.Hubbe@dell.com>
Signed-off-by: NJon Mason <jdmason@kudzu.us>

Add the code to initialize the memory windows in the hardware.
This includes setting up the requester ID table, and figuring out
which BAR corresponds to which memory window. (Seeing the switch
can be configured with any number of BARs.)

Also, seeing the device doesn't have hardware for scratchpads or
determining the link status, we create a shared memory window that has
these features. A magic number with a version component will be used
to determine if the other side's driver is actually up.

The shared memory window also informs the other side of the
size and count of the local memory windows.
Signed-off-by: NLogan Gunthorpe <logang@deltatee.com>
Reviewed-by: NStephen Bates <sbates@raithlin.com>
Reviewed-by: NKurt Schwemmer <kurt.schwemmer@microsemi.com>
Acked-by: NAllen Hubbe <Allen.Hubbe@dell.com>
Signed-off-by: NJon Mason <jdmason@kudzu.us>

Seeing the Switchtec NTB hardware shares the same endpoint as the
management endpoint we utilize the class_interface API to register
an NTB driver for every Switchtec device in the system that has the
NTB class code.
Signed-off-by: NLogan Gunthorpe <logang@deltatee.com>
Reviewed-by: NStephen Bates <sbates@raithlin.com>
Reviewed-by: NKurt Schwemmer <kurt.schwemmer@microsemi.com>
Acked-by: NAllen Hubbe <Allen.Hubbe@dell.com>
Acked-by: NBjorn Helgaas <bhelgaas@google.com>
Signed-off-by: NJon Mason <jdmason@kudzu.us>

With Switchtec hardware it's impossible to get the alignment parameters
for a peer's memory window until the peer's driver has configured its
windows. Strictly speaking, the link doesn't have to be up for this,
but the link being up is the only way the client can tell that
the other side has been configured.

This patch converts ntb_transport and ntb_perf to use this function after
the link goes up. This simplifies these clients slightly because they
no longer have to store the alignment parameters. It also tweaks
ntb_tool so that peer_mw_trans will print zero if it is run before
the link goes up.
Signed-off-by: NLogan Gunthorpe <logang@deltatee.com>
Acked-by: NAllen Hubbe <Allen.Hubbe@dell.com>
Signed-off-by: NJon Mason <jdmason@kudzu.us>

In order for the Switchtec NTB code to handle link change events we
create a notifier callback in the switchtec code which gets called
whenever an appropriate event interrupt occurs.

In order to preserve userspace's ability to follow these events,
we compare the event count with a stored copy from last time we
checked.
Signed-off-by: NLogan Gunthorpe <logang@deltatee.com>
Reviewed-by: NStephen Bates <sbates@raithlin.com>
Reviewed-by: NKurt Schwemmer <kurt.schwemmer@microsemi.com>
Acked-by: NBjorn Helgaas <bhelgaas@google.com>
Signed-off-by: NJon Mason <jdmason@kudzu.us>

We export the class pointer symbol and add an extern define in the
Switchtec header file.
Signed-off-by: NLogan Gunthorpe <logang@deltatee.com>
Reviewed-by: NStephen Bates <sbates@raithlin.com>
Reviewed-by: NKurt Schwemmer <kurt.schwemmer@microsemi.com>
Acked-by: NBjorn Helgaas <bhelgaas@google.com>
Signed-off-by: NJon Mason <jdmason@kudzu.us>

Create the switchtec.h header in include/linux with hardware defines
and the switchtec_dev structure. Both moved directly from switchtec.c.
This is a prep patch for creating an NTB driver for Switchtec.
Signed-off-by: NLogan Gunthorpe <logang@deltatee.com>
Reviewed-by: NStephen Bates <sbates@raithlin.com>
Reviewed-by: NKurt Schwemmer <kurt.schwemmer@microsemi.com>
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: NBjorn Helgaas <bhelgaas@google.com>
Signed-off-by: NJon Mason <jdmason@kudzu.us>

The updates this merge window added several bogus default enablement for
new features.  We don't do that.  If people want new behavior, they ask
for it.

One 'default n' was also removed as pointless.  That's great, but there
were eight other ones in the same file that were left alone.

Fix it up.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add "silead,home-button" property to entries for tablets which have
a capacitive home button (typically a windows logo on the front).

This new property is checked for by the new capacitive home button
support in the silead touchscreen driver.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>

There is no need to #define the license of the driver, just put it in
the MODULE_LICENSE() line directly as a text string.

This allows tools that check that the module license matches the source
code license to work properly, as there is no need to unwind the
unneeded dereference.

Cc: "David S. Miller" <davem@davemloft.net>
Cc: Andreas Kemnade <andreas@kemnade.info>
Cc: Johan Hovold <johan@kernel.org>
Reported-by: NPhilippe Ombredanne <pombredanne@nexb.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: NPhilippe Ombredanne <pombredanne@nexb.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch fixes the dma_mapping_error call to use the correct dma_addr
which is inside the ibmvnic_vpd struct. Moreover, it fixes an uninitialized
warning regarding a local dma_addr variable which is not used anymore.

Fixes: 4e6759be ("ibmvnic: Feature implementation of VPD for the ibmvnic driver")
Reported-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NDesnes A. Nunes do Rosario <desnesn@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When call to register_netdevice() (called from ipvlan_link_new()) fails,
we call ipvlan_uninit() (through ndo_uninit()) to destroy the ipvlan
port. After returning unsuccessfully from register_netdevice() we go
ahead and call ipvlan_port_destroy() again which causes NULL pointer
dereference panic. Fix the issue by making ipvlan_init() and
ipvlan_uninit() call symmetric.

The ipvlan port will now be created inside ipvlan_init() and will be
destroyed in ipvlan_uninit().

Fixes: 2ad7bf36 (ipvlan: Initial check-in of the IPVLAN driver)
Signed-off-by: NGirish Moodalbail <girish.moodalbail@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In the cases where len is too long, the error return path fails to
kfree allocated buffers buf and usb_reg_buf.  The simplest fix is to
perform the sanity check on len before the allocations to avoid having
to do the kfree'ing in the first place.

Detected by CoverityScan, CID#1452258,1452259 ("Resource Leak")

Fixes: 59f73e2a ("rsi: check length before USB read/write register")
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

pcmv_setup() is only used when the badge4 driver is built-in, but not
when it is a loadable module:

  drivers/pcmcia/sa1111_badge4.c:153:122: error: 'pcmv_setup' defined but not used [-Werror=unused-function]

This adds an #ifdef to avoid the definition of the unused function in
the modular case.

Link: http://lkml.kernel.org/r/20170911201133.3421636-1-arnd@arndb.deSigned-off-by: NArnd Bergmann <arnd@arndb.de>
Cc: Russell King <rmk@armlinux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Save a bit of cleanup code by leveraging newly added
devm_register_reboot_notifier().

[akpm@linux-foundation.org: small cleanup: avoid 80-col tricks]
Link: http://lkml.kernel.org/r/20170411160615.9784-1-andrew.smirnov@gmail.comSigned-off-by: NAndrey Smirnov <andrew.smirnov@gmail.com>
Acked-by: NGuenter Roeck <linux@roeck-us.net>
Cc: Chris Healy <cphealy@gmail.com>
Cc: Wim Van Sebroeck <wim@iguana.be>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In case of error, 'dma_map_sg()' returns 0, not a negative value.  There
is BUG_ON() in 'dma_map_sg_attrs()' which makes sure of that.

Link: http://lkml.kernel.org/r/d4235bd2b9274e99f6c86ea71b1fa1c7bd8d0c08.1505687047.git.christophe.jaillet@wanadoo.frSigned-off-by: NChristophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: NLogan Gunthorpe <logang@deltatee.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Christian K_nig <christian.koenig@amd.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

drivers/rapidio/devices/rio_mport_cdev.c: fix resource leak in error handling path in 'rio_dma_transfer()'

If 'dma_map_sg()', we should branch to the existing error handling path
to free some resources before returning.

Link: http://lkml.kernel.org/r/61292a4f369229eee03394247385e955027283f8.1505687047.git.christophe.jaillet@wanadoo.frSigned-off-by: NChristophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: NLogan Gunthorpe <logang@deltatee.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Christian K_nig <christian.koenig@amd.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

rio_device_id are not supposed to change at runtime.  rio driver is
working with const 'id_table'.  So mark the non-const rio_device_id
structs as const.

Link: http://lkml.kernel.org/r/1503734627-6058-2-git-send-email-arvind.yadav.cs@gmail.com
Link: http://lkml.kernel.org/r/1503734627-6058-3-git-send-email-arvind.yadav.cs@gmail.com
Link: http://lkml.kernel.org/r/1503734627-6058-4-git-send-email-arvind.yadav.cs@gmail.com
Link: http://lkml.kernel.org/r/1503734627-6058-5-git-send-email-arvind.yadav.cs@gmail.com
Link: http://lkml.kernel.org/r/1503734627-6058-6-git-send-email-arvind.yadav.cs@gmail.comSigned-off-by: NArvind Yadav <arvind.yadav.cs@gmail.com>
Acked-by: NAlexandre Bounine <alexandre.bounine@idt.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In order to test the ordering of WARN format strings, actually include
one in LKDTM.

Link: http://lkml.kernel.org/r/1510100869-73751-2-git-send-email-keescook@chromium.orgSigned-off-by: NKees Cook <keescook@chromium.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

We cap the upper bound of "fbnum" but we also need to check for
negatives or make the type unsigned.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

The pointer fbi is dereferenced with par = fbi->par before there is a
null check on fbi, hence there is a potential null pointer dereference
on a null par.  Fix this by moving the dereference after the null
pointer check.

Detected by CoverityScan, CID#1461301 ("Dereference before null check")
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Cc: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

Pass information to the match offload on whether or not the repr is the
ingress or egress dev. Only accept tunnel matches if repr is the egress
dev.

This means rules such as the following are successfully offloaded:
tc .. add dev vxlan0 .. enc_dst_port 4789 .. action redirect dev nfp_p0

While rules such as the following are rejected:
tc .. add dev nfp_p0 .. enc_dst_port 4789 .. action redirect dev vxlan0

Also reject non tunnel flows that are offloaded to an egress dev.
Non tunnel matches assume that the offload dev is the ingress port and
offload a match accordingly.

Fixes: 611aec10 ("nfp: compile flower vxlan tunnel metadata match fields")
Signed-off-by: NJohn Hurley <john.hurley@netronome.com>
Reviewed-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Register a callback for offloading flows that have a repr as their egress
device. The new egdev_register function is added to net-next for the 4.15
release.
Signed-off-by: NJohn Hurley <john.hurley@netronome.com>
Reviewed-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The PF netdev is used for data transfer for reprs, so reprs inherit the
maximum MTU settings of the PF netdev.

Fixes: 5de73ee4 ("nfp: general representor implementation")
Signed-off-by: NDirk van der Merwe <dirk.vandermerwe@netronome.com>
Reviewed-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Correct typo in vlan receive MAC stats. Previously the MAC statistics
reported in ethtool for vlan receive contained a typo resulting in ethtool
reporting rx_vlan_reveive_ok instead of rx_vlan_received_ok.

Fixes: a5950182 ("nfp: map mac_stats and vf_cfg BARs")
Fixes: 098ce840 ("nfp: report MAC statistics in ethtool")
Reported-by: NBrendan Galloway <brendan.galloway@netronome.com>
Signed-off-by: NPieter Jansen van Vuuren <pieter.jansenvanvuuren@netronome.com>
Reviewed-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: NSimon Horman <simon.horman@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Hardware has no notion of new or last mask id, instead it makes use of the
message type (i.e. add flow or del flow) in combination with a single bit
in metadata flags to determine when to add or delete a mask id. Previously
we made use of the new or last flags to indicate that a new mask should be
allocated or deallocated, respectively. This incorrect behaviour is fixed
by making use single bit in metadata flags to indicate mask allocation or
deallocation.

Fixes: 43f84b72 ("nfp: add metadata to each flow offload")
Signed-off-by: NPieter Jansen van Vuuren <pieter.jansenvanvuuren@netronome.com>
Reviewed-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Looks like this was mistakenly added to the tree as part of
commit 186b3c99 ("virtio-net: support XDP_REDIRECT").
Signed-off-by: NJoel Stanley <joel@jms.id.au>
Acked-by: NJason Wang <jasowang@redhat.com>
Acked-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

On machines using rfkill interface the buffer needs to have been
allocated before the initial use (memset) of it.
Reported-by: NValdis Kletnieks <valdis.kletnieks@vt.edu>
Signed-off-by: NMario Limonciello <mario.limonciello@dell.com>
Tested-by: NValdis Kletnieks <valdis.kletnieks@vt.edu>
Signed-off-by: NDarren Hart (VMware) <dvhart@infradead.org>

dell-wmi and dell-smbios-wmi are dependent upon dell-wmi-descriptor
finishing probe successfully to probe themselves.

Currently if dell-wmi-descriptor fails probing in a non-recoverable way
(such as invalid header) dell-wmi and dell-smbios-wmi will continue to
try to redo probing due to deferred probing.

To solve this have the dependent drivers query the dell-wmi-descriptor
driver whether the descriptor has been determined valid. The possible
results are:
-ENODEV: Descriptor GUID missing from WMI bus
-EPROBE_DEFER: Descriptor not yet probed, dependent driver should wait
 and use deferred probing
< 0: Descriptor probed, invalid.  Dependent driver should return an
 error.
0: Successful descriptor probe, dependent driver can continue

Successful descriptor probe still doesn't mean that the descriptor driver
is necessarily bound at the time of initialization of dependent driver.
Userspace can unbind the driver, so all methods used from driver
should still be verified to return success values otherwise deferred
probing be used.
Signed-off-by: NMario Limonciello <mario.limonciello@dell.com>
Reviewed-by: NPali Rohár <pali.rohar@gmail.com>
Signed-off-by: NDarren Hart (VMware) <dvhart@infradead.org>

devm_kzalloc will return NULL pointer if no memory was allocated.
This should be checked.  This problem also existed when the driver
was dell-wmi.c.
Signed-off-by: NMario Limonciello <mario.limonciello@dell.com>
Reviewed-by: NPali Rohár <pali.rohar@gmail.com>
Signed-off-by: NDarren Hart (VMware) <dvhart@infradead.org>

The check for "active" children in __pm_runtime_set_status(), when
trying to set the parent device status to "suspended", doesn't
really make sense, because in fact it is not invalid to set the
status of a device with runtime PM disabled to "suspended" in any
case.  It is invalid to enable runtime PM for a device with its
status set to "suspended" while its child_count reference counter
is nonzero, but the check in __pm_runtime_set_status() doesn't
really cover that situation.

For this reason, drop the children check from __pm_runtime_set_status()
and add a check against child_count reference counters of "suspended"
devices to pm_runtime_enable().

Fixes: a8636c89 (PM / Runtime: Don't allow to suspend a device with an active child)
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: NUlf Hansson <ulf.hansson@linaro.org>
Reviewed-by: NJohan Hovold <johan@kernel.org>

The default max_cache_size_bytes for dm-bufio is meant to be the lesser
of 25% of the size of the vmalloc area and 2% of the size of lowmem.
However, on 32-bit systems the intermediate result in the expression

    (VMALLOC_END - VMALLOC_START) * DM_BUFIO_VMALLOC_PERCENT / 100

overflows, causing the wrong result to be computed.  For example, on a
32-bit system where the vmalloc area is 520093696 bytes, the result is
1174405 rather than the expected 130023424, which makes the maximum
cache size much too small (far less than 2% of lowmem).  This causes
severe performance problems for dm-verity users on affected systems.

Fix this by using mult_frac() to correctly multiply by a percentage.  Do
this for all places in dm-bufio that multiply by a percentage.  Also
replace (VMALLOC_END - VMALLOC_START) with VMALLOC_TOTAL, which contrary
to the comment is now defined in include/linux/vmalloc.h.

Depends-on: 9993bc63 ("sched/x86: Fix overflow in cyc2ns_offset")
Fixes: 95d402f0 ("dm: add bufio")
Cc: <stable@vger.kernel.org> # v3.2+
Signed-off-by: NEric Biggers <ebiggers@google.com>
Signed-off-by: NMike Snitzer <snitzer@redhat.com>