`genwqe_user_vmap()` calls `get_user_pages_fast()` and if the return
value is less than the number of pages requested, it frees the pages and
returns an error (`-EFAULT`).  However, it fails to consider a negative
error return value from `get_user_pages_fast()`.  In that case, the test
`if (rc < m->nr_pages)` will be false (due to promotion of `rc` to a
large `unsigned int`) and the code will continue on to call
`genwqe_map_pages()` with an invalid list of page pointers.  Fix it by
bailing out if `get_user_pages_fast()` returns a negative error value.
Signed-off-by: NIan Abbott <abbotti@mev.co.uk>
Cc: <stable@vger.kernel.org> # 3.14.x # 3.15.x # 3.16.x # 3.17.x
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The checkpatch.pl script got improved. I ran it on the latest GenWQE
sources and fixed what it complained about.
Signed-off-by: NFrank Haverkamp <haver@linux.vnet.ibm.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Updated email address of co-author.
Signed-off-by: NFrank Haverkamp <haver@linux.vnet.ibm.com>
Signed-off-by: NMichael Jung <mijung@gmx.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

GenWQE used to call pci_enable_msi_block to allocate a desired number
of MSI's. If that was not possible pci_enable_msi_block returned with a
smaller number which might be possible to allocate. GenWQE then called
pci_enable_msi_block with that number.

Since commit a30d0108
"GenWQE: Use pci_enable_msi_exact() instead of pci_enable_msi_block()"
pci_enable_msi_exact is used which fails if the desired number of MSI's
was not possible to allocate. Change GenWQE to use pci_enable_msi_range
to restore the old behavior.
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: NAlexander Gordeev <agordeev@redhat.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch implements the callbacks and functions necessary to have EEH
recovery support.

It adds a config option to enable or disable explicit calls to trigger
platform specific mechanisms on error recovery paths. This option is
enabled by default only on PPC64 systems and can be overritten via
debugfs. If this option is enabled, on the error recovery path the
driver will call pci_channel_offline() to check for error condition and
issue non-raw MMIO reads to trigger early EEH detection in case of
hardware failures. This is necessary since the driver MMIO helper
funtions use raw accessors.
Signed-off-by: NKleber Sacilotto de Souza <klebers@linux.vnet.ibm.com>
Acked-by: NFrank Haverkamp <haver@linux.vnet.ibm.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Function genwqe_free_sync_sgl() returns the value of variable 'rc'. 'rc' is
only set in the error paths, thus initialize it by 0. Coverity CID 1204242.
Signed-off-by: NChristian Engelmayer <cengelma@gmx.at>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

As result of deprecation of MSI-X/MSI enablement functions
pci_enable_msix() and pci_enable_msi_block() all drivers using these two
interfaces need to be updated to use the new pci_enable_msi_range()  or
pci_enable_msi_exact() and pci_enable_msix_range() or
pci_enable_msix_exact() interfaces.
Signed-off-by: NAlexander Gordeev <agordeev@redhat.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Acked-by: NFrank Haverkamp <haver@linux.vnet.ibm.com>
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

When being used in a multithreaded application there were problems
with memory pages/cachelines accessed by multiple threads/cpus at the
same time, while doing DMA transfers to/from those. To avoid such
situations this fix is creating a copy of the first and the last page
if it is not fully used. The data is copied from user-space into those
pages and results are copied back when the DDCB-request is
successfully finished.
Signed-off-by: NFrank Haverkamp <haver@linux.vnet.ibm.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Fix a casting to u32 where u64 would be appropriate.
The bad casting made the driver unusable.
Signed-off-by: NFrank Haverkamp <haver@linux.vnet.ibm.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Fengguang Wu used CF=-D__CHECK_ENDIAN__ to check the GenWQE driver for
endian issues. Sparse found a couple of those. Most of them were caused
by not correctly handling __be64/32 and __u64/32. Those I was able to
fix with appropriate castings.

One more serious issue was the ATS entry in struct genwqe_ddcb_cmd.
The kernel expected it in big-endian, but the type was defined __u64.
I decided that it is better to keep the interface consistent using
host endian byte-odering instead of having a mixture. With this change
the kernel likes to see host endian byte order for the ATS entry. That
would have been an interface change, if someone would have used the
driver already. Since this is not the case, I hope it is ok to fix it
now.

For the genqwe_readq/writeq/readl/writel functions I enforced the casts.

It still complains, as far as I can see, about some copy_to/from_user()
usages:

  CHECK   char-misc/drivers/misc/genwqe/card_dev.c
char-misc/arch/x86/include/asm/uaccess.h:625:18: warning: incorrect type in argument 1 (different modifiers)
char-misc/arch/x86/include/asm/uaccess.h:625:18:    expected void *<noident>
char-misc/arch/x86/include/asm/uaccess.h:625:18:    got void const *from
char-misc/arch/x86/include/asm/uaccess.h:625:18: warning: incorrect type in argument 1 (different modifiers)
char-misc/arch/x86/include/asm/uaccess.h:625:18:    expected void *<noident>
char-misc/arch/x86/include/asm/uaccess.h:625:18:    got void const *from
char-misc/arch/x86/include/asm/uaccess.h:625:18: warning: incorrect type in argument 1 (different modifiers)
char-misc/arch/x86/include/asm/uaccess.h:625:18:    expected void *<noident>
char-misc/arch/x86/include/asm/uaccess.h:625:18:    got void const *from
char-misc/arch/x86/include/asm/uaccess.h:625:18: warning: incorrect type in argument 1 (different modifiers)
char-misc/arch/x86/include/asm/uaccess.h:625:18:    expected void *<noident>
char-misc/arch/x86/include/asm/uaccess.h:625:18:    got void const *from
  CC [M]  drivers/misc/genwqe/card_dev.o
  CHECK   char-misc/drivers/misc/genwqe/card_ddcb.c
char-misc/arch/x86/include/asm/uaccess.h:625:18: warning: incorrect type in argument 1 (different modifiers)
char-misc/arch/x86/include/asm/uaccess.h:625:18:    expected void *<noident>
char-misc/arch/x86/include/asm/uaccess.h:625:18:    got void const *from
char-misc/arch/x86/include/asm/uaccess.h:625:18: warning: incorrect type in argument 1 (different modifiers)
char-misc/arch/x86/include/asm/uaccess.h:625:18:    expected void *<noident>
char-misc/arch/x86/include/asm/uaccess.h:625:18:    got void const *from
  CC [M]  drivers/misc/genwqe/card_ddcb.o
  LD [M]  drivers/misc/genwqe/genwqe_card.o

I appreciate some help from you to figure out what is causig those, and
making a proposal how to fix them.

I included the missing header file to fix the
implicit-function-declaration warning when using dynamic_hex_dump.
Signed-off-by: NFrank Haverkamp <haver@linux.vnet.ibm.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Miscelanous functionality used in the other GenWQE driver parts.
Signed-off-by: NFrank Haverkamp <haver@linux.vnet.ibm.com>
Co-authors: Joerg-Stephan Vogt <jsvogt@de.ibm.com>,
            Michael Jung <MIJUNG@de.ibm.com>,
            Michael Ruettger <michael@ibmra.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>