iommu/amd: Make domain_flush_pages as global function

- Rename domain_flush_pages() -> amd_iommu_domain_flush_pages() and make
it as global function.

- Rename amd_iommu_domain_flush_tlb_pde() -> amd_iommu_domain_flush_all()
and make it as static.

- Convert v1 page table (io_pgtble.c) to use amd_iommu_domain_flush_pages().

Signed-off-by: Vasant Hegde <vasant.hegde@amd.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20231122090215.6191-9-vasant.hegde@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

iommu/amd: Consolidate amd_iommu_domain_flush_complete() call

Call amd_iommu_domain_flush_complete() from domain_flush_pages().
That way we can remove explicit call of amd_iommu_domain_flush_complete()
from various places.

Signed-off-by: Vasant Hegde <vasant.hegde@amd.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20231122090215.6191-8-vasant.hegde@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

iommu/amd: Access/Dirty bit support in IOPTEs

IOMMU advertises Access/Dirty bits if the extended feature register reports
it. Relevant AMD IOMMU SDM ref[0] "1.3.8 Enhanced Support for Access and
Dirty Bits"

To enable it set the DTE flag in bits 7 and 8 to enable access, or
access+dirty. With that, the IOMMU starts marking the D and A flags on
every Memory Request or ATS translation request. It is on the VMM side to
steer whether to enable dirty tracking or not, rather than wrongly doing in
IOMMU. Relevant AMD IOMMU SDM ref [0], "Table 7. Device Table Entry (DTE)
Field Definitions" particularly the entry "HAD".

To actually toggle on and off it's relatively simple as it's setting 2 bits
on DTE and flush the device DTE cache.

To get what's dirtied use existing AMD io-pgtable support, by walking the
pagetables over each IOVA, with fetch_pte(). The IOTLB flushing is left to
the caller (much like unmap), and iommu_dirty_bitmap_record() is the one
adding page-ranges to invalidate. This allows caller to batch the flush
over a big span of IOVA space, without the iommu wondering about when to
flush.

Worthwhile sections from AMD IOMMU SDM:

"2.2.3.1 Host Access Support"
"2.2.3.2 Host Dirty Support"

For details on how IOMMU hardware updates the dirty bit see, and expects
from its consequent clearing by CPU:

"2.2.7.4 Updating Accessed and Dirty Bits in the Guest Address Tables"
"2.2.7.5 Clearing Accessed and Dirty Bits"

Quoting the SDM:

"The setting of accessed and dirty status bits in the page tables is
visible to both the CPU and the peripheral when sharing guest page tables.
The IOMMU interlocked operations to update A and D bits must be 64-bit
operations and naturally aligned on a 64-bit boundary"

.. and for the IOMMU update sequence to Dirty bit, essentially is states:

1. Decodes the read and write intent from the memory access.
2. If P=0 in the page descriptor, fail the access.
3. Compare the A & D bits in the descriptor with the read and write
intent in the request.
4. If the A or D bits need to be updated in the descriptor:
* Start atomic operation.
* Read the descriptor as a 64-bit access.
* If the descriptor no longer appears to require an update, release the
atomic lock with
no further action and continue to step 5.
* Calculate the new A & D bits.
* Write the descriptor as a 64-bit access.
* End atomic operation.
5. Continue to the next stage of translation or to the memory access.

Access/Dirty bits readout also need to consider the non-default page-sizes
(aka replicated PTEs as mentined by manual), as AMD supports all powers of
two (except 512G) page sizes.

Select IOMMUFD_DRIVER only if IOMMUFD is enabled considering that IOMMU
dirty tracking requires IOMMUFD.

Link: https://lore.kernel.org/r/20231024135109.73787-12-joao.m.martins@oracle.com
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

iommu/amd: Use page mode macros in fetch_pte()

Use the page mode macros instead of magic numbers in fetch_pte.

Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Cc: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Jerry Snitselaar <jsnitsel@redhat.com>
Reviewed-by: Vasant Hegde <vasant.hegde@amd.com>
Link: https://lore.kernel.org/r/20230420080718.523132-1-jsnitsel@redhat.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

iommu/amd: Allocate page table using numa locality info

Introduce 'struct protection_domain->nid' variable. It will contain
IOMMU NUMA node ID. And allocate page table pages using IOMMU numa
locality info. This optimizes page table walk by IOMMU.

Signed-off-by: Vasant Hegde <vasant.hegde@amd.com>
Link: https://lore.kernel.org/r/20230321092348.6127-2-vasant.hegde@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

iommu/amd/io-pgtable: Implement unmap_pages io_pgtable_ops callback

Implement the io_pgtable_ops->unmap_pages() callback for AMD driver
and deprecate io_pgtable_ops->unmap callback.

Also if fetch_pte() returns NULL then return from unmap_mapages()
instead of trying to continue to unmap remaining pages.

Suggested-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Vasant Hegde <vasant.hegde@amd.com>
Link: https://lore.kernel.org/r/20220825063939.8360-3-vasant.hegde@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

iommu/amd/io-pgtable: Implement map_pages io_pgtable_ops callback

Implement the io_pgtable_ops->map_pages() callback for AMD driver.
Also deprecate io_pgtable->map callback.

Suggested-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Vasant Hegde <vasant.hegde@amd.com>
Link: https://lore.kernel.org/r/20220825063939.8360-2-vasant.hegde@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

iommu/amd: Use try_cmpxchg64 in alloc_pte and free_clear_pte

Use try_cmpxchg64 instead of cmpxchg64 (*ptr, old, new) != old in
alloc_pte and free_clear_pte. cmpxchg returns success in ZF flag, so this
change saves a compare after cmpxchg (and related move instruction
in front of cmpxchg). Also, remove racy explicit assignment to pteval
when cmpxchg fails, this is what try_cmpxchg does implicitly from
*pte in an atomic way.

Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20220525145416.10816-1-ubizjak@gmail.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

iommu/amd: Fix I/O page table memory leak

The current logic updates the I/O page table mode for the domain
before calling the logic to free memory used for the page table.
This results in IOMMU page table memory leak, and can be observed
when launching VM w/ pass-through devices.

Fix by freeing the memory used for page table before updating the mode.

Cc: Joerg Roedel <joro@8bytes.org>
Reported-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Tested-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Fixes: e42ba0633064 ("iommu/amd: Restructure code for freeing page table")
Link: https://lore.kernel.org/all/20220118194720.urjgi73b7c3tq2o6@oracle.com/
Link: https://lore.kernel.org/r/20220210154745.11524-1-suravee.suthikulpanit@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

iommu/amd: Use put_pages_list

page->freelist is for the use of slab. We already have the ability
to free a list of pages in the core mm, but it requires the use of a
list_head and for the pages to be chained together through page->lru.
Switch the AMD IOMMU code over to using free_pages_list().

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
[rm: split from original patch, cosmetic tweaks]
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/73af128f651aaa1f38f69e586c66765a88ad2de0.1639753638.git.robin.murphy@arm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

iommu/amd: Simplify pagetable freeing

For reasons unclear, pagetable freeing is an effectively recursive
method implemented via an elaborate system of templated functions that
turns out to account for 25% of the object file size. Implementing it
using regular straightforward recursion makes the code simpler, and
seems like a good thing to do before we work on it further. As part of
that, also fix the types to avoid all the needless casting back and
forth which just gets in the way.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/d3d00c9f3fa0df4756b867072c201e6e82f9ce39.1639753638.git.robin.murphy@arm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

iommu: Streamline iommu_iova_to_phys()

If people are going to insist on calling iommu_iova_to_phys()
pointlessly and expecting it to work, we can at least do ourselves a
favour by handling those cases in the core code, rather than repeatedly
across an inconsistent handful of drivers.

Since all the existing drivers implement the internal callback, and any
future ones are likely to want to work with iommu-dma which relies on
iova_to_phys a fair bit, we may as well remove that currently-redundant
check as well and consider it mandatory.

Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/f564f3f6ff731b898ff7a898919bf871c2c7745a.1626354264.git.robin.murphy@arm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

iommu/amd: Fix sleeping in atomic in increase_address_space()

increase_address_space() calls get_zeroed_page(gfp) under spin_lock with
disabled interrupts. gfp flags passed to increase_address_space() may allow
sleeping, so it comes to this:

BUG: sleeping function called from invalid context at mm/page_alloc.c:4342
in_atomic(): 1, irqs_disabled(): 1, pid: 21555, name: epdcbbf1qnhbsd8

Call Trace:
dump_stack+0x66/0x8b
___might_sleep+0xec/0x110
__alloc_pages_nodemask+0x104/0x300
get_zeroed_page+0x15/0x40
iommu_map_page+0xdd/0x3e0
amd_iommu_map+0x50/0x70
iommu_map+0x106/0x220
vfio_iommu_type1_ioctl+0x76e/0x950 [vfio_iommu_type1]
do_vfs_ioctl+0xa3/0x6f0
ksys_ioctl+0x66/0x70
__x64_sys_ioctl+0x16/0x20
do_syscall_64+0x4e/0x100
entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fix this by moving get_zeroed_page() out of spin_lock/unlock section.

Fixes: 754265bcab ("iommu/amd: Fix race in increase_address_space()")
Signed-off-by: Andrey Ryabinin <arbn@yandex-team.com>
Acked-by: Will Deacon <will@kernel.org>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20210217143004.19165-1-arbn@yandex-team.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

iommu/amd: Introduce iommu_v1_map_page and iommu_v1_unmap_page

These implement map and unmap for AMD IOMMU v1 pagetable, which
will be used by the IO pagetable framework.

Also clean up unused extern function declarations.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Link: https://lore.kernel.org/r/20201215073705.123786-13-suravee.suthikulpanit@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

iommu/amd: Introduce iommu_v1_iova_to_phys

This implements iova_to_phys for AMD IOMMU v1 pagetable,
which will be used by the IO page table framework.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Link: https://lore.kernel.org/r/20201215073705.123786-12-suravee.suthikulpanit@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

iommu/amd: Refactor fetch_pte to use struct amd_io_pgtable

To simplify the fetch_pte function. There is no functional change.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Link: https://lore.kernel.org/r/20201215073705.123786-11-suravee.suthikulpanit@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

iommu/amd: Rename variables to be consistent with struct io_pgtable_ops

There is no functional change.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Link: https://lore.kernel.org/r/20201215073705.123786-10-suravee.suthikulpanit@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

iommu/amd: Remove amd_iommu_domain_get_pgtable

Since the IO page table root and mode parameters have been moved into
the struct amd_io_pg, the function is no longer needed. Therefore,
remove it along with the struct domain_pgtable.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Link: https://lore.kernel.org/r/20201215073705.123786-9-suravee.suthikulpanit@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

iommu/amd: Restructure code for freeing page table

By consolidate logic into v1_free_pgtable helper function,
which is called from IO page table framework.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Link: https://lore.kernel.org/r/20201215073705.123786-8-suravee.suthikulpanit@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

iommu/amd: Move IO page table related functions

Preparing to migrate to use IO page table framework.
There is no functional change.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Link: https://lore.kernel.org/r/20201215073705.123786-7-suravee.suthikulpanit@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

iommu/amd: Prepare for generic IO page table framework

Add initial hook up code to implement generic IO page table framework.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Link: https://lore.kernel.org/r/20201215073705.123786-3-suravee.suthikulpanit@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>