1. 10 9月, 2015 11 次提交
  2. 09 9月, 2015 4 次提交
    • J
      xen/privcmd: Further s/MFN/GFN/ clean-up · a13d7201
      Julien Grall 提交于
      The privcmd code is mixing the usage of GFN and MFN within the same
      functions which make the code difficult to understand when you only work
      with auto-translated guests.
      
      The privcmd driver is only dealing with GFN so replace all the mention
      of MFN into GFN.
      
      The ioctl structure used to map foreign change has been left unchanged
      given that the userspace is using it. Nonetheless, add a comment to
      explain the expected value within the "mfn" field.
      Signed-off-by: NJulien Grall <julien.grall@citrix.com>
      Reviewed-by: NDavid Vrabel <david.vrabel@citrix.com>
      Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
      a13d7201
    • J
      xen: Use correctly the Xen memory terminologies · 0df4f266
      Julien Grall 提交于
      Based on include/xen/mm.h [1], Linux is mistakenly using MFN when GFN
      is meant, I suspect this is because the first support for Xen was for
      PV. This resulted in some misimplementation of helpers on ARM and
      confused developers about the expected behavior.
      
      For instance, with pfn_to_mfn, we expect to get an MFN based on the name.
      Although, if we look at the implementation on x86, it's returning a GFN.
      
      For clarity and avoid new confusion, replace any reference to mfn with
      gfn in any helpers used by PV drivers. The x86 code will still keep some
      reference of pfn_to_mfn which may be used by all kind of guests
      No changes as been made in the hypercall field, even
      though they may be invalid, in order to keep the same as the defintion
      in xen repo.
      
      Note that page_to_mfn has been renamed to xen_page_to_gfn to avoid a
      name to close to the KVM function gfn_to_page.
      
      Take also the opportunity to simplify simple construction such
      as pfn_to_mfn(page_to_pfn(page)) into xen_page_to_gfn. More complex clean up
      will come in follow-up patches.
      
      [1] http://xenbits.xen.org/gitweb/?p=xen.git;a=commitdiff;h=e758ed14f390342513405dd766e874934573e6cbSigned-off-by: NJulien Grall <julien.grall@citrix.com>
      Reviewed-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
      Acked-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>
      Acked-by: NWei Liu <wei.liu2@citrix.com>
      Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
      0df4f266
    • J
      arm/xen: implement correctly pfn_to_mfn · 5192b35d
      Julien Grall 提交于
      After the commit introducing convertion between DMA and guest addresses,
      all the callers of pfn_to_mfn are expecting to get a GFN (Guest Frame
      Number). On ARM, all the guests are auto-translated so the GFN is equal
      to the Linux PFN (Pseudo-physical Frame Number).
      
      The current implementation may return an MFN if the caller is passing a
      PFN associated to a mapped foreign grant. In pratice, I haven't seen
      the problem on running guest but we should fix it for the sake of
      correctness.
      
      Correct the implementation by always returning the pfn passed in parameter.
      
      A follow-up patch will take care to rename pfn_to_mfn to a suitable
      name.
      Signed-off-by: NJulien Grall <julien.grall@citrix.com>
      Reviewed-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
      Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
      5192b35d
    • J
      xen: Make clear that swiotlb and biomerge are dealing with DMA address · 32e09870
      Julien Grall 提交于
      The swiotlb is required when programming a DMA address on ARM when a
      device is not protected by an IOMMU.
      
      In this case, the DMA address should always be equal to the machine address.
      For DOM0 memory, Xen ensure it by have an identity mapping between the
      guest address and host address. However, when mapping a foreign grant
      reference, the 1:1 model doesn't work.
      
      For ARM guest, most of the callers of pfn_to_mfn expects to get a GFN
      (Guest Frame Number), i.e a PFN (Page Frame Number) from the Linux point
      of view given that all ARM guest are auto-translated.
      
      Even though the name pfn_to_mfn is misleading, we need to ensure that
      those caller get a GFN and not by mistake a MFN. In pratical, I haven't
      seen error related to this but we should fix it for the sake of
      correctness.
      
      In order to fix the implementation of pfn_to_mfn on ARM in a follow-up
      patch, we have to introduce new helpers to return the DMA from a PFN and
      the invert.
      
      On x86, the new helpers will be an alias of pfn_to_mfn and mfn_to_pfn.
      
      The helpers will be used in swiotlb and xen_biovec_phys_mergeable.
      
      This is necessary in the latter because we have to ensure that the
      biovec code will not try to merge a biovec using foreign page and
      another using Linux memory.
      
      Lastly, the helper mfn_to_local_pfn has been renamed to bfn_to_local_pfn
      given that the only usage was in swiotlb.
      Signed-off-by: NJulien Grall <julien.grall@citrix.com>
      Reviewed-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
      Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
      32e09870
  3. 06 9月, 2015 6 次提交
  4. 05 9月, 2015 1 次提交
    • V
      genalloc: add name arg to gen_pool_get() and devm_gen_pool_create() · 73858173
      Vladimir Zapolskiy 提交于
      This change modifies gen_pool_get() and devm_gen_pool_create() client
      interfaces adding one more argument "name" of a gen_pool object.
      
      Due to implementation gen_pool_get() is capable to retrieve only one
      gen_pool associated with a device even if multiple gen_pools are created,
      fortunately right at the moment it is sufficient for the clients, hence
      provide NULL as a valid argument on both producer devm_gen_pool_create()
      and consumer gen_pool_get() sides.
      
      Because only one created gen_pool per device is addressable, explicitly
      add a restriction to devm_gen_pool_create() to create only one gen_pool
      per device, this implies two possible error codes returned by the
      function, account it on client side (only misc/sram).  This completes
      client side changes related to genalloc updates.
      
      [akpm@linux-foundation.org: gen_pool_get() cleanup]
      Signed-off-by: NVladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
      Cc: Philipp Zabel <p.zabel@pengutronix.de>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: Russell King <linux@arm.linux.org.uk>
      Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
      Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
      Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>
      Cc: Shawn Guo <shawnguo@kernel.org>
      Cc: Sascha Hauer <kernel@pengutronix.de>
      Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      73858173
  5. 28 8月, 2015 2 次提交
  6. 27 8月, 2015 3 次提交
    • R
      ARM: software-based priviledged-no-access support · a5e090ac
      Russell King 提交于
      Provide a software-based implementation of the priviledged no access
      support found in ARMv8.1.
      
      Userspace pages are mapped using a different domain number from the
      kernel and IO mappings.  If we switch the user domain to "no access"
      when we enter the kernel, we can prevent the kernel from touching
      userspace.
      
      However, the kernel needs to be able to access userspace via the
      various user accessor functions.  With the wrapping in the previous
      patch, we can temporarily enable access when the kernel needs user
      access, and re-disable it afterwards.
      
      This allows us to trap non-intended accesses to userspace, eg, caused
      by an inadvertent dereference of the LIST_POISON* values, which, with
      appropriate user mappings setup, can be made to succeed.  This in turn
      can allow use-after-free bugs to be further exploited than would
      otherwise be possible.
      Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
      a5e090ac
    • R
      ARM: entry: provide uaccess assembly macro hooks · 2190fed6
      Russell King 提交于
      Provide hooks into the kernel entry and exit paths to permit control
      of userspace visibility to the kernel.  The intended use is:
      
      - on entry to kernel from user, uaccess_disable will be called to
        disable userspace visibility
      - on exit from kernel to user, uaccess_enable will be called to
        enable userspace visibility
      - on entry from a kernel exception, uaccess_save_and_disable will be
        called to save the current userspace visibility setting, and disable
        access
      - on exit from a kernel exception, uaccess_restore will be called to
        restore the userspace visibility as it was before the exception
        occurred.
      
      These hooks allows us to keep userspace visibility disabled for the
      vast majority of the kernel, except for localised regions where we
      want to explicitly access userspace.
      Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
      2190fed6
    • R
      ARM: entry: get rid of multiple macro definitions · aa06e5c1
      Russell King 提交于
      The following structure is just asking for trouble:
      
       #ifdef CONFIG_symbol
      	.macro foo
      	...
      	.endm
      	.macro bar
      	...
      	.endm
      	.macro baz
      	...
      	.endm
       #else
      	.macro foo
      	...
      	.endm
      	.macro bar
      	...
      	.endm
       #ifdef CONFIG_symbol2
      	.macro baz
      	...
      	.endm
       #else
      	.macro baz
      	...
      	.endm
       #endif
       #endif
      
      such as one defintion being updated, but the other definitions miss out.
      Where the contents of a macro needs to be conditional, the hint is in
      the first clause of this very sentence.  "contents" "conditional".  Not
      multiple separate definitions, especially not when much of the macro
      is the same between different configs.
      
      This patch fixes this bad style, which had caused the Thumb2 code to
      miss-out on the uaccess updates.
      Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
      aa06e5c1
  7. 26 8月, 2015 1 次提交
  8. 25 8月, 2015 8 次提交
  9. 24 8月, 2015 1 次提交
  10. 22 8月, 2015 3 次提交