Commit Graph

74 Commits

Author SHA1 Message Date
Christian Brauner
602e2300de UPSTREAM: rust: add PidNamespace
The lifetime of `PidNamespace` is bound to `Task` and `struct pid`.

The `PidNamespace` of a `Task` doesn't ever change once the `Task` is
alive. A `unshare(CLONE_NEWPID)` or `setns(fd_pidns/pidfd, CLONE_NEWPID)`
will not have an effect on the calling `Task`'s pid namespace. It will
only effect the pid namespace of children created by the calling `Task`.
This invariant guarantees that after having acquired a reference to a
`Task`'s pid namespace it will remain unchanged.

When a task has exited and been reaped `release_task()` will be called.
This will set the `PidNamespace` of the task to `NULL`. So retrieving
the `PidNamespace` of a task that is dead will return `NULL`. Note, that
neither holding the RCU lock nor holding a referencing count to the
`Task` will prevent `release_task()` being called.

In order to retrieve the `PidNamespace` of a `Task` the
`task_active_pid_ns()` function can be used. There are two cases to
consider:

(1) retrieving the `PidNamespace` of the `current` task (2) retrieving
the `PidNamespace` of a non-`current` task

From system call context retrieving the `PidNamespace` for case (1) is
always safe and requires neither RCU locking nor a reference count to be
held. Retrieving the `PidNamespace` after `release_task()` for current
will return `NULL` but no codepath like that is exposed to Rust.

Retrieving the `PidNamespace` from system call context for (2) requires
RCU protection. Accessing `PidNamespace` outside of RCU protection
requires a reference count that must've been acquired while holding the
RCU lock. Note that accessing a non-`current` task means `NULL` can be
returned as the non-`current` task could have already passed through
`release_task()`.

To retrieve (1) the `current_pid_ns!()` macro should be used which
ensure that the returned `PidNamespace` cannot outlive the calling
scope. The associated `current_pid_ns()` function should not be called
directly as it could be abused to created an unbounded lifetime for
`PidNamespace`. The `current_pid_ns!()` macro allows Rust to handle the
common case of accessing `current`'s `PidNamespace` without RCU
protection and without having to acquire a reference count.

For (2) the `task_get_pid_ns()` method must be used. This will always
acquire a reference on `PidNamespace` and will return an `Option` to
force the caller to explicitly handle the case where `PidNamespace` is
`None`, something that tends to be forgotten when doing the equivalent
operation in `C`. Missing RCU primitives make it difficult to perform
operations that are otherwise safe without holding a reference count as
long as RCU protection is guaranteed. But it is not important currently.
But we do want it in the future.

Note for (2) the required RCU protection around calling
`task_active_pid_ns()` synchronizes against putting the last reference
of the associated `struct pid` of `task->thread_pid`. The `struct pid`
stored in that field is used to retrieve the `PidNamespace` of the
caller. When `release_task()` is called `task->thread_pid` will be
`NULL`ed and `put_pid()` on said `struct pid` will be delayed in
`free_pid()` via `call_rcu()` allowing everyone with an RCU protected
access to the `struct pid` acquired from `task->thread_pid` to finish.

Link: https://lore.kernel.org/r/20241002-brauner-rust-pid_namespace-v5-1-a90e70d44fde@kernel.org
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>

Bug: 429146594
(cherry picked from commit e0020ba6cbcbfbaaa50c3d4b610c7caa36459624)
Change-Id: Ib7d3b257fe9b6f11f8171924e2a146abb52b9bb7
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
2025-07-02 13:08:23 +00:00
Alice Ryhl
f03d4f7490 UPSTREAM: mm: rust: add abstraction for struct mm_struct
Patch series "Rust support for mm_struct, vm_area_struct, and mmap", v16.

This updates the vm_area_struct support to use the approach we discussed
at LPC where there are several different Rust wrappers for vm_area_struct
depending on the kind of access you have to the vma.  Each case allows a
different set of operations on the vma.

This includes an MM MAINTAINERS entry as proposed by Lorenzo:
https://lore.kernel.org/all/33e64b12-aa07-4e78-933a-b07c37ff1d84@lucifer.local/

This patch (of 9):

These abstractions allow you to reference a `struct mm_struct` using both
mmgrab and mmget refcounts.  This is done using two Rust types:

* Mm - represents an mm_struct where you don't know anything about the
  value of mm_users.
* MmWithUser - represents an mm_struct where you know at compile time
  that mm_users is non-zero.

This allows us to encode in the type system whether a method requires that
mm_users is non-zero or not.  For instance, you can always call
`mmget_not_zero` but you can only call `mmap_read_lock` when mm_users is
non-zero.

The struct is called Mm to keep consistency with the C side.

The ability to obtain `current->mm` is added later in this series.

The mm module is defined to only exist when CONFIG_MMU is set.  This
avoids various errors due to missing types and functions when CONFIG_MMU
is disabled.  More fine-grained cfgs can be considered in the future.  See
the thread at [1] for more info.

Link: https://lkml.kernel.org/r/20250408-vma-v16-9-d8b446e885d9@google.com
Link: https://lkml.kernel.org/r/20250408-vma-v16-1-d8b446e885d9@google.com
Link: https://lore.kernel.org/all/202503091916.QousmtcY-lkp@intel.com/
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Acked-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Acked-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Acked-by: Balbir Singh <balbirs@nvidia.com>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Cc: Alex Gaynor <alex.gaynor@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benno Lossin <benno.lossin@proton.me>
Cc: Björn Roy Baron <bjorn3_gh@protonmail.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jann Horn <jannh@google.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miguel Ojeda <ojeda@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Trevor Gross <tmgross@umich.edu>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Bug: 429146594
(cherry picked from commit 5bb9ed6cdfeb75883652fd0ed3e3885083a92b4b)
Change-Id: I33a9a37795ec426c051abb881a0425ab545c8cad
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
2025-07-02 13:08:21 +00:00
Alice Ryhl
1acd3b312f Revert "FROMLIST: mm: rust: add abstraction for struct mm_struct"
This reverts commit 4deea7dce7.

Bug: 429146594
Change-Id: Ide43b384264dc8b69cf0a3c5bb1d8b71fe4742a7
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
2025-07-02 13:08:18 +00:00
Kalesh Singh
d44ff7a3ed ANDROID: 16K: Introduce rust __page_*() helpers
Rust versions of the __PAGE_* helpers in
    include/linux/page_size_compat.h

Bug: 414665621
Bug: 383389337
Change-Id: I928bd825ba97ae4435ee13eb9c317038e98700cf
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
2025-05-16 12:18:08 +00:00
Greg Kroah-Hartman
ac5b2508c1 Merge 677088b7fa ("rust: init: fix Zeroable implementation for Option<NonNull<T>> and Option<KBox<T>>") into android16-6.12
Steps on the way to 6.12.20

Resolves merge conflicts in:
	rust/kernel/sync.rs

Change-Id: I2e13aa71c635af1cbbc66a28b113bb43c4b16053
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2025-04-22 09:04:39 -07:00
Greg Kroah-Hartman
b3fb80bdc6 Merge 6.12.19 into android16-6.12
GKI (arm64) relevant 48 out of 271 changes, affecting 92 files +576/-223
  5b414ed3bb Revert "of: reserved-memory: Fix using wrong number of cells to get property 'alignment'" [1 file, +2/-2]
  48a934fc47 Revert "mm/page_alloc.c: don't show protection in zone's ->lowmem_reserve[] for empty zone" [1 file, +1/-2]
  88310caff6 Bluetooth: Add check for mgmt_alloc_skb() in mgmt_remote_name() [1 file, +2/-0]
  7841180342 Bluetooth: Add check for mgmt_alloc_skb() in mgmt_device_connected() [1 file, +3/-0]
  2d448dbd47 userfaultfd: do not block on locking a large folio with raised refcount [1 file, +16/-1]
  f57e89c1cb block: fix conversion of GPT partition name to 7-bit [1 file, +1/-1]
  9426f38372 mm/page_alloc: fix uninitialized variable [1 file, +1/-0]
  79636d2981 mm: abort vma_modify() on merge out of memory failure [1 file, +8/-4]
  605f53f13b mm: don't skip arch_sync_kernel_mappings() in error paths [2 files, +6/-4]
  9ed33c7bac mm: fix finish_fault() handling for large folios [1 file, +10/-5]
  576a2f4c43 hwpoison, memory_hotplug: lock folio before unmap hwpoisoned folio [1 file, +4/-1]
  2e66d69941 mm: memory-hotplug: check folio ref count first in do_migrate_range [1 file, +7/-13]
  3c63fb6ef7 nvme-pci: use sgls for all user requests if possible [2 files, +13/-4]
  9dedafd86e nvme-ioctl: fix leaked requests on mapping error [1 file, +8/-4]
  084819b0d8 net: gso: fix ownership in __udp_gso_segment [1 file, +6/-2]
  1688acf477 perf/core: Fix pmus_lock vs. pmus_srcu ordering [1 file, +2/-2]
  a899adf706 HID: hid-steam: Fix use-after-free when detaching device [1 file, +1/-1]
  8aa8a40c76 ppp: Fix KMSAN uninit-value warning with bpf [1 file, +19/-9]
  b71cd95764 ethtool: linkstate: migrate linkstate functions to support multi-PHY setups [1 file, +15/-8]
  9c1d09cdbc net: ethtool: plumb PHY stats to PHY drivers [7 files, +167/-2]
  639c703529 net: ethtool: netlink: Allow NULL nlattrs when getting a phy_device [9 files, +19/-18]
  30e8aee778 vlan: enforce underlying device type [1 file, +2/-1]
  5d609f0d2f exfat: fix just enough dentries but allocate a new cluster to dir [1 file, +1/-1]
  c897b8ec46 exfat: fix soft lockup in exfat_clear_bitmap [3 files, +16/-7]
  611015122d exfat: short-circuit zero-byte writes in exfat_file_write_iter [1 file, +1/-1]
  2b484789e9 net-timestamp: support TCP GSO case for a few missing flags [1 file, +7/-4]
  b08e290324 ublk: set_params: properly check if parameters can be applied [1 file, +5/-2]
  b5741e4b9e sched/fair: Fix potential memory corruption in child_cfs_rq_on_list [1 file, +4/-2]
  39c2b2767e xhci: Restrict USB4 tunnel detection for USB3 devices to Intel hosts [1 file, +8/-0]
  4ea3319f3e usb: hub: lack of clearing xHC resources [1 file, +33/-0]
  0cab185c73 usb: quirks: Add DELAY_INIT and NO_LPM for Prolific Mass Storage Card Reader [1 file, +4/-0]
  079a3e52f3 usb: typec: ucsi: Fix NULL pointer access [1 file, +7/-6]
  840afbea3f usb: gadget: u_ether: Set is_suspend flag if remote wakeup fails [1 file, +2/-2]
  ced69d88eb usb: dwc3: Set SUSPENDENABLE soon after phy init [3 files, +45/-30]
  35db1f1829 usb: dwc3: gadget: Prevent irq storm when TH re-executes [2 files, +13/-13]
  b387312527 usb: typec: ucsi: increase timeout for PPM reset operations [1 file, +1/-1]
  4bf6c57a89 usb: gadget: Set self-powered based on MaxPower and bmAttributes [1 file, +11/-5]
  dcd7ffdefb usb: gadget: Fix setting self-powered state on suspend [1 file, +2/-1]
  395011ee82 usb: gadget: Check bmAttributes only if configuration is valid [1 file, +1/-1]
  012b98cdb5 acpi: typec: ucsi: Introduce a ->poll_cci method [7 files, +25/-12]
  d7015bb3c5 xhci: pci: Fix indentation in the PCI device ID definitions [1 file, +4/-4]
  ea39f99864 usb: xhci: Enable the TRB overfetch quirk on VIA VL805 [3 files, +10/-5]
  4e8df56636 char: misc: deallocate static minor in error path [1 file, +1/-1]
  b50e18791f drivers: core: fix device leak in __fw_devlink_relax_cycles() [1 file, +1/-0]
  a684bad77e mm: hugetlb: Add huge page size param to huge_ptep_get_and_clear() [16 files, +46/-28]
  6ad9643aa5 fs/netfs/read_pgpriv2: skip folio queues without `marks3` [1 file, +3/-2]
  5bc6e5b10f fs/netfs/read_collect: fix crash due to uninitialized `prev` variable [1 file, +11/-10]
  86b7ebddab uprobes: Fix race in uprobe_free_utask [1 file, +1/-1]

Changes in 6.12.19
        x86/amd_nb: Use rdmsr_safe() in amd_get_mmconfig_range()
        rust: block: fix formatting in GenDisk doc
        drm/i915/dsi: convert to struct intel_display
        drm/i915/dsi: Use TRANS_DDI_FUNC_CTL's own port width macro
        gpio: vf610: use generic device_get_match_data()
        gpio: vf610: add locking to gpio direction functions
        cifs: Remove symlink member from cifs_open_info_data union
        smb311: failure to open files of length 1040 when mounting with SMB3.1.1 POSIX extensions
        btrfs: fix data overwriting bug during buffered write when block size < page size
        x86/microcode/AMD: Add some forgotten models to the SHA check
        loongarch: Use ASM_REACHABLE
        rust: workqueue: remove unneeded ``#[allow(clippy::new_ret_no_self)]`
        rust: sort global Rust flags
        rust: types: avoid repetition in `{As,From}Bytes` impls
        rust: enable `clippy::undocumented_unsafe_blocks` lint
        rust: enable `clippy::unnecessary_safety_comment` lint
        rust: enable `clippy::unnecessary_safety_doc` lint
        rust: enable `clippy::ignored_unit_patterns` lint
        rust: enable `rustdoc::unescaped_backticks` lint
        rust: init: remove unneeded `#[allow(clippy::disallowed_names)]`
        rust: sync: remove unneeded `#[allow(clippy::non_send_fields_in_send_ty)]`
        rust: introduce `.clippy.toml`
        rust: replace `clippy::dbg_macro` with `disallowed_macros`
        rust: provide proper code documentation titles
        rust: enable Clippy's `check-private-items`
        Documentation: rust: add coding guidelines on lints
        rust: start using the `#[expect(...)]` attribute
        Documentation: rust: discuss `#[expect(...)]` in the guidelines
        rust: error: make conversion functions public
        rust: error: optimize error type to use nonzero
        rust: alloc: add `Allocator` trait
        rust: alloc: separate `aligned_size` from `krealloc_aligned`
        rust: alloc: rename `KernelAllocator` to `Kmalloc`
        rust: alloc: implement `ReallocFunc`
        rust: alloc: make `allocator` module public
        rust: alloc: implement `Allocator` for `Kmalloc`
        rust: alloc: add module `allocator_test`
        rust: alloc: implement `Vmalloc` allocator
        rust: alloc: implement `KVmalloc` allocator
        rust: alloc: add __GFP_NOWARN to `Flags`
        rust: alloc: implement kernel `Box`
        rust: treewide: switch to our kernel `Box` type
        rust: alloc: remove extension of std's `Box`
        rust: alloc: add `Box` to prelude
        rust: alloc: introduce `ArrayLayout`
        rust: alloc: implement kernel `Vec` type
        rust: alloc: implement `IntoIterator` for `Vec`
        rust: alloc: implement `collect` for `IntoIter`
        rust: treewide: switch to the kernel `Vec` type
        rust: alloc: remove `VecExt` extension
        rust: alloc: add `Vec` to prelude
        rust: error: use `core::alloc::LayoutError`
        rust: error: check for config `test` in `Error::name`
        rust: alloc: implement `contains` for `Flags`
        rust: alloc: implement `Cmalloc` in module allocator_test
        rust: str: test: replace `alloc::format`
        rust: alloc: update module comment of alloc.rs
        kbuild: rust: remove the `alloc` crate and `GlobalAlloc`
        MAINTAINERS: add entry for the Rust `alloc` module
        drm/panic: avoid reimplementing Iterator::find
        drm/panic: remove unnecessary borrow in alignment_pattern
        drm/panic: prefer eliding lifetimes
        drm/panic: remove redundant field when assigning value
        drm/panic: correctly indent continuation of line in list item
        drm/panic: allow verbose boolean for clarity
        drm/panic: allow verbose version check
        rust: kbuild: expand rusttest target for macros
        rust: fix size_t in bindgen prototypes of C builtins
        rust: map `__kernel_size_t` and friends also to usize/isize
        rust: use custom FFI integer types
        rust: alloc: Fix `ArrayLayout` allocations
        Revert "of: reserved-memory: Fix using wrong number of cells to get property 'alignment'"
        tracing: tprobe-events: Fix a memory leak when tprobe with $retval
        tracing: tprobe-events: Reject invalid tracepoint name
        stmmac: loongson: Pass correct arg to PCI function
        LoongArch: Convert unreachable() to BUG()
        LoongArch: Use polling play_dead() when resuming from hibernation
        LoongArch: Set max_pfn with the PFN of the last page
        LoongArch: KVM: Add interrupt checking for AVEC
        LoongArch: KVM: Reload guest CSR registers after sleep
        LoongArch: KVM: Fix GPA size issue about VM
        HID: appleir: Fix potential NULL dereference at raw event handle
        ksmbd: fix type confusion via race condition when using ipc_msg_send_request
        ksmbd: fix out-of-bounds in parse_sec_desc()
        ksmbd: fix use-after-free in smb2_lock
        ksmbd: fix bug on trap in smb2_lock
        gpio: rcar: Use raw_spinlock to protect register access
        gpio: aggregator: protect driver attr handlers against module unload
        ALSA: seq: Avoid module auto-load handling at event delivery
        ALSA: hda: intel: Add Dell ALC3271 to power_save denylist
        ALSA: hda/realtek - add supported Mic Mute LED for Lenovo platform
        ALSA: hda/realtek: update ALC222 depop optimize
        btrfs: fix a leaked chunk map issue in read_one_chunk()
        hwmon: (peci/dimmtemp) Do not provide fake thresholds data
        drm/amd/display: Fix null check for pipe_ctx->plane_state in resource_build_scaling_params
        drm/amdkfd: Fix NULL Pointer Dereference in KFD queue
        drm/amd/pm: always allow ih interrupt from fw
        drm/imagination: avoid deadlock on fence release
        drm/imagination: Hold drm_gem_gpuva lock for unmap
        drm/imagination: only init job done fences once
        drm/radeon: Fix rs400_gpu_init for ATI mobility radeon Xpress 200M
        Revert "mm/page_alloc.c: don't show protection in zone's ->lowmem_reserve[] for empty zone"
        Revert "selftests/mm: remove local __NR_* definitions"
        platform/x86: thinkpad_acpi: Add battery quirk for ThinkPad X131e
        x86/boot: Sanitize boot params before parsing command line
        x86/cacheinfo: Validate CPUID leaf 0x2 EDX output
        x86/cpu: Validate CPUID leaf 0x2 EDX output
        x86/cpu: Properly parse CPUID leaf 0x2 TLB descriptor 0x63
        drm/xe: Add staging tree for VM binds
        drm/xe/hmm: Style- and include fixes
        drm/xe/hmm: Don't dereference struct page pointers without notifier lock
        drm/xe/vm: Fix a misplaced #endif
        drm/xe/vm: Validate userptr during gpu vma prefetching
        mptcp: fix 'scheduling while atomic' in mptcp_pm_nl_append_new_local_addr
        drm/xe: Fix GT "for each engine" workarounds
        drm/xe: Fix fault mode invalidation with unbind
        drm/xe/userptr: properly setup pfn_flags_mask
        drm/xe/userptr: Unmap userptrs in the mmu notifier
        Bluetooth: Add check for mgmt_alloc_skb() in mgmt_remote_name()
        Bluetooth: Add check for mgmt_alloc_skb() in mgmt_device_connected()
        wifi: cfg80211: regulatory: improve invalid hints checking
        wifi: nl80211: reject cooked mode if it is set along with other flags
        selftests/damon/damos_quota_goal: handle minimum quota that cannot be further reduced
        selftests/damon/damos_quota: make real expectation of quota exceeds
        selftests/damon/damon_nr_regions: set ops update for merge results check to 100ms
        selftests/damon/damon_nr_regions: sort collected regiosn before checking with min/max boundaries
        rapidio: add check for rio_add_net() in rio_scan_alloc_net()
        rapidio: fix an API misues when rio_add_net() fails
        dma: kmsan: export kmsan_handle_dma() for modules
        s390/traps: Fix test_monitor_call() inline assembly
        NFS: fix nfs_release_folio() to not deadlock via kcompactd writeback
        userfaultfd: do not block on locking a large folio with raised refcount
        block: fix conversion of GPT partition name to 7-bit
        mm/page_alloc: fix uninitialized variable
        mm: abort vma_modify() on merge out of memory failure
        mm: memory-failure: update ttu flag inside unmap_poisoned_folio
        mm: don't skip arch_sync_kernel_mappings() in error paths
        mm: fix finish_fault() handling for large folios
        hwpoison, memory_hotplug: lock folio before unmap hwpoisoned folio
        mm: memory-hotplug: check folio ref count first in do_migrate_range
        wifi: iwlwifi: mvm: clean up ROC on failure
        wifi: iwlwifi: mvm: don't try to talk to a dead firmware
        wifi: iwlwifi: limit printed string from FW file
        wifi: iwlwifi: Free pages allocated when failing to build A-MSDU
        wifi: iwlwifi: Fix A-MSDU TSO preparation
        HID: google: fix unused variable warning under !CONFIG_ACPI
        HID: intel-ish-hid: Fix use-after-free issue in hid_ishtp_cl_remove()
        HID: intel-ish-hid: Fix use-after-free issue in ishtp_hid_remove()
        coredump: Only sort VMAs when core_sort_vma sysctl is set
        nvme-pci: add support for sgl metadata
        nvme-pci: use sgls for all user requests if possible
        nvme-ioctl: fix leaked requests on mapping error
        wifi: mac80211: Support parsing EPCS ML element
        wifi: mac80211: fix MLE non-inheritance parsing
        wifi: mac80211: fix vendor-specific inheritance
        drm/fbdev-helper: Move color-mode lookup into 4CC format helper
        drm/fbdev: Add memory-agnostic fbdev client
        drm: Add client-agnostic setup helper
        drm/fbdev-ttm: Support struct drm_driver.fbdev_probe
        drm/nouveau: Run DRM default client setup
        drm/nouveau: select FW caching
        bluetooth: btusb: Initialize .owner field of force_poll_sync_fops
        nvme-tcp: add basic support for the C2HTermReq PDU
        nvme-tcp: fix potential memory corruption in nvme_tcp_recv_pdu()
        nvmet-tcp: Fix a possible sporadic response drops in weakly ordered arch
        ALSA: hda/realtek: Remove (revert) duplicate Ally X config
        net: gso: fix ownership in __udp_gso_segment
        caif_virtio: fix wrong pointer check in cfv_probe()
        perf/core: Fix pmus_lock vs. pmus_srcu ordering
        hwmon: (pmbus) Initialise page count in pmbus_identify()
        hwmon: (ntc_thermistor) Fix the ncpXXxh103 sensor table
        hwmon: (ad7314) Validate leading zero bits and return error
        tracing: probe-events: Remove unused MAX_ARG_BUF_LEN macro
        drm/imagination: Fix timestamps in firmware traces
        ALSA: usx2y: validate nrpacks module parameter on probe
        llc: do not use skb_get() before dev_queue_xmit()
        hwmon: fix a NULL vs IS_ERR_OR_NULL() check in xgene_hwmon_probe()
        drm/sched: Fix preprocessor guard
        be2net: fix sleeping while atomic bugs in be_ndo_bridge_getlink
        net: hns3: make sure ptp clock is unregister and freed if hclge_ptp_get_cycle returns an error
        drm/i915/color: Extract intel_color_modeset()
        drm/i915: Plumb 'dsb' all way to the plane hooks
        drm/xe: Remove double pageflip
        HID: hid-steam: Fix use-after-free when detaching device
        net: ipa: Fix v4.7 resource group names
        net: ipa: Fix QSB data for v4.7
        net: ipa: Enable checksum for IPA_ENDPOINT_AP_MODEM_{RX,TX} for v4.7
        ppp: Fix KMSAN uninit-value warning with bpf
        ethtool: linkstate: migrate linkstate functions to support multi-PHY setups
        net: ethtool: plumb PHY stats to PHY drivers
        net: ethtool: netlink: Allow NULL nlattrs when getting a phy_device
        vlan: enforce underlying device type
        x86/sgx: Fix size overflows in sgx_encl_create()
        exfat: fix just enough dentries but allocate a new cluster to dir
        exfat: fix soft lockup in exfat_clear_bitmap
        exfat: short-circuit zero-byte writes in exfat_file_write_iter
        net-timestamp: support TCP GSO case for a few missing flags
        ublk: set_params: properly check if parameters can be applied
        sched/fair: Fix potential memory corruption in child_cfs_rq_on_list
        nvme-tcp: fix signedness bug in nvme_tcp_init_connection()
        net: dsa: mt7530: Fix traffic flooding for MMIO devices
        mctp i3c: handle NULL header address
        net: ipv6: fix dst ref loop in ila lwtunnel
        net: ipv6: fix missing dst ref drop in ila lwtunnel
        gpio: rcar: Fix missing of_node_put() call
        Revert "drivers/card_reader/rtsx_usb: Restore interrupt based detection"
        usb: renesas_usbhs: Call clk_put()
        xhci: Restrict USB4 tunnel detection for USB3 devices to Intel hosts
        usb: renesas_usbhs: Use devm_usb_get_phy()
        usb: hub: lack of clearing xHC resources
        usb: quirks: Add DELAY_INIT and NO_LPM for Prolific Mass Storage Card Reader
        usb: typec: ucsi: Fix NULL pointer access
        usb: renesas_usbhs: Flush the notify_hotplug_work
        usb: gadget: u_ether: Set is_suspend flag if remote wakeup fails
        usb: atm: cxacru: fix a flaw in existing endpoint checks
        usb: dwc3: Set SUSPENDENABLE soon after phy init
        usb: dwc3: gadget: Prevent irq storm when TH re-executes
        usb: typec: ucsi: increase timeout for PPM reset operations
        usb: typec: tcpci_rt1711h: Unmask alert interrupts to fix functionality
        usb: gadget: Set self-powered based on MaxPower and bmAttributes
        usb: gadget: Fix setting self-powered state on suspend
        usb: gadget: Check bmAttributes only if configuration is valid
        kbuild: userprogs: use correct lld when linking through clang
        acpi: typec: ucsi: Introduce a ->poll_cci method
        rust: finish using custom FFI integer types
        rust: map `long` to `isize` and `char` to `u8`
        xhci: pci: Fix indentation in the PCI device ID definitions
        usb: xhci: Enable the TRB overfetch quirk on VIA VL805
        KVM: SVM: Set RFLAGS.IF=1 in C code, to get VMRUN out of the STI shadow
        KVM: SVM: Save host DR masks on CPUs with DebugSwap
        KVM: SVM: Drop DEBUGCTL[5:2] from guest's effective value
        KVM: SVM: Suppress DEBUGCTL.BTF on AMD
        KVM: x86: Snapshot the host's DEBUGCTL in common x86
        KVM: SVM: Manually context switch DEBUGCTL if LBR virtualization is disabled
        KVM: x86: Snapshot the host's DEBUGCTL after disabling IRQs
        KVM: x86: Explicitly zero EAX and EBX when PERFMON_V2 isn't supported by KVM
        cdx: Fix possible UAF error in driver_override_show()
        mei: me: add panther lake P DID
        mei: vsc: Use "wakeuphostint" when getting the host wakeup GPIO
        intel_th: pci: Add Arrow Lake support
        intel_th: pci: Add Panther Lake-H support
        intel_th: pci: Add Panther Lake-P/U support
        char: misc: deallocate static minor in error path
        drivers: core: fix device leak in __fw_devlink_relax_cycles()
        slimbus: messaging: Free transaction ID in delayed interrupt scenario
        bus: mhi: host: pci_generic: Use pci_try_reset_function() to avoid deadlock
        eeprom: digsy_mtc: Make GPIO lookup table match the device
        drivers: virt: acrn: hsm: Use kzalloc to avoid info leak in pmcmd_ioctl
        iio: filter: admv8818: Force initialization of SDO
        iio: light: apds9306: fix max_scale_nano values
        iio: dac: ad3552r: clear reset status flag
        iio: adc: ad7192: fix channel select
        iio: adc: at91-sama5d2_adc: fix sama7g5 realbits value
        mm: hugetlb: Add huge page size param to huge_ptep_get_and_clear()
        arm64: hugetlb: Fix huge_ptep_get_and_clear() for non-present ptes
        fs/netfs/read_pgpriv2: skip folio queues without `marks3`
        fs/netfs/read_collect: fix crash due to uninitialized `prev` variable
        kbuild: hdrcheck: fix cross build with clang
        ALSA: hda: realtek: fix incorrect IS_REACHABLE() usage
        nvme-tcp: Fix a C2HTermReq error message
        docs: rust: remove spurious item in `expect` list
        Revert "KVM: e500: always restore irqs"
        Revert "KVM: PPC: e500: Use __kvm_faultin_pfn() to handle page faults"
        Revert "KVM: PPC: e500: Mark "struct page" pfn accessed before dropping mmu_lock"
        Revert "KVM: PPC: e500: Mark "struct page" dirty in kvmppc_e500_shadow_map()"
        KVM: e500: always restore irqs
        uprobes: Fix race in uprobe_free_utask
        selftests/bpf: Clean up open-coded gettid syscall invocations
        x86/mm: Don't disable PCID when INVLPG has been fixed by microcode
        wifi: iwlwifi: pcie: Fix TSO preparation
        Linux 6.12.19

Change-Id: Ia0c2b2c6a95b53a66e21505ed6ba756c6b0a2388
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2025-04-17 03:02:04 -07:00
Greg Kroah-Hartman
dfed1574cd Merge 1ef4cf5f98 ("rust: alloc: update module comment of alloc.rs") into android16-6.12
Steps on the way to 6.12.18

Resolves merge conflicts in:
	rust/kernel/types.rs
	scripts/Makefile.build

Change-Id: I1a0d7a30074e2532f53b9c9d4cf0e8346d57ffef
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
[Re-resolved rust/kernel/types.rs <mmaurer@google.com>]
Signed-off-by: Matthew Maurer <mmaurer@google.com>
2025-04-07 05:41:55 -07:00
Miguel Ojeda
6db379b34a rust: remove leftover mentions of the alloc crate
commit 374908a15af4cd60862ebc51a6e012ace2212c76 upstream.

In commit 392e34b6bc22 ("kbuild: rust: remove the `alloc` crate and
`GlobalAlloc`") we stopped using the upstream `alloc` crate.

Thus remove a few leftover mentions treewide.

Cc: stable@vger.kernel.org # Also to 6.12.y after the `alloc` backport lands
Fixes: 392e34b6bc22 ("kbuild: rust: remove the `alloc` crate and `GlobalAlloc`")
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://lore.kernel.org/r/20250303171030.1081134-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-22 12:54:23 -07:00
Gary Guo
641ecd0d0a rust: use custom FFI integer types
commit d072acda4862f095ec9056979b654cc06a22cc68 upstream.

Currently FFI integer types are defined in libcore. This commit creates
the `ffi` crate and asks bindgen to use that crate for FFI integer types
instead of `core::ffi`.

This commit is preparatory and no type changes are made in this commit
yet.

Signed-off-by: Gary Guo <gary@garyguo.net>
Link: https://lore.kernel.org/r/20240913213041.395655-4-gary@garyguo.net
[ Added `rustdoc`, `rusttest` and KUnit tests support. Rebased on top of
  `rust-next` (e.g. migrated more `core::ffi` cases). Reworded crate
  docs slightly and formatted. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-13 13:01:49 +01:00
Danilo Krummrich
0ca66a44e2 rust: alloc: implement kernel Vec type
commit 2aac4cd7dae3d7bb0e0ddec2561b2ee4cbe6c8f6 upstream.

`Vec` provides a contiguous growable array type with contents allocated
with the kernel's allocators (e.g. `Kmalloc`, `Vmalloc` or `KVmalloc`).

In contrast to Rust's stdlib `Vec` type, the kernel `Vec` type considers
the kernel's GFP flags for all appropriate functions, always reports
allocation failures through `Result<_, AllocError>` and remains
independent from unstable features.

[ This patch starts using a new unstable feature, `inline_const`, but
  it was stabilized in Rust 1.79.0, i.e. the next version after the
  minimum one, thus it will not be an issue. - Miguel ]

Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20241004154149.93856-17-dakr@kernel.org
[ Cleaned `rustdoc` unescaped backtick warning, added a couple more
  backticks elsewhere, fixed typos, sorted `feature`s, rewrapped
  documentation lines. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-13 13:01:45 +01:00
Danilo Krummrich
34eb8dcb62 rust: alloc: remove extension of std's Box
commit e8c6ccdbcaaf31f26c0fffd4073edd0b0147cdc6 upstream.

Now that all existing `Box` users were moved to the kernel `Box` type,
remove the `BoxExt` extension and all other related extensions.

Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20241004154149.93856-14-dakr@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-13 13:01:45 +01:00
Miguel Ojeda
706d4296b8 rust: start using the #[expect(...)] attribute
commit 1f9ed172545687e5c04c77490a45896be6d2e459 upstream.

In Rust, it is possible to `allow` particular warnings (diagnostics,
lints) locally, making the compiler ignore instances of a given warning
within a given function, module, block, etc.

It is similar to `#pragma GCC diagnostic push` + `ignored` + `pop` in C:

    #pragma GCC diagnostic push
    #pragma GCC diagnostic ignored "-Wunused-function"
    static void f(void) {}
    #pragma GCC diagnostic pop

But way less verbose:

    #[allow(dead_code)]
    fn f() {}

By that virtue, it makes it possible to comfortably enable more
diagnostics by default (i.e. outside `W=` levels) that may have some
false positives but that are otherwise quite useful to keep enabled to
catch potential mistakes.

The `#[expect(...)]` attribute [1] takes this further, and makes the
compiler warn if the diagnostic was _not_ produced. For instance, the
following will ensure that, when `f()` is called somewhere, we will have
to remove the attribute:

    #[expect(dead_code)]
    fn f() {}

If we do not, we get a warning from the compiler:

    warning: this lint expectation is unfulfilled
     --> x.rs:3:10
      |
    3 | #[expect(dead_code)]
      |          ^^^^^^^^^
      |
      = note: `#[warn(unfulfilled_lint_expectations)]` on by default

This means that `expect`s do not get forgotten when they are not needed.

See the next commit for more details, nuances on its usage and
documentation on the feature.

The attribute requires the `lint_reasons` [2] unstable feature, but it
is becoming stable in 1.81.0 (to be released on 2024-09-05) and it has
already been useful to clean things up in this patch series, finding
cases where the `allow`s should not have been there.

Thus, enable `lint_reasons` and convert some of our `allow`s to `expect`s
where possible.

This feature was also an example of the ongoing collaboration between
Rust and the kernel -- we tested it in the kernel early on and found an
issue that was quickly resolved [3].

Cc: Fridtjof Stoldt <xfrednet@gmail.com>
Cc: Urgau <urgau@numericable.fr>
Link: https://rust-lang.github.io/rfcs/2383-lint-reasons.html#expect-lint-attribute [1]
Link: https://github.com/rust-lang/rust/issues/54503 [2]
Link: https://github.com/rust-lang/rust/issues/114557 [3]
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Trevor Gross <tmgross@umich.edu>
Tested-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Gary Guo <gary@garyguo.net>
Link: https://lore.kernel.org/r/20240904204347.168520-18-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-13 13:01:42 +01:00
Alice Ryhl
4deea7dce7 FROMLIST: mm: rust: add abstraction for struct mm_struct
These abstractions allow you to reference a `struct mm_struct` using
both mmgrab and mmget refcounts. This is done using two Rust types:

* Mm - represents an mm_struct where you don't know anything about the
  value of mm_users.
* MmWithUser - represents an mm_struct where you know at compile time
  that mm_users is non-zero.

This allows us to encode in the type system whether a method requires
that mm_users is non-zero or not. For instance, you can always call
`mmget_not_zero` but you can only call `mmap_read_lock` when mm_users is
non-zero.

The struct is called Mm to keep consistency with the C side.

The ability to obtain `current->mm` is added later in this series.

Acked-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> (for mm bits)
Signed-off-by: Alice Ryhl <aliceryhl@google.com>

Bug: 370906207
Link: https://lore.kernel.org/all/20250115-vma-v12-1-375099ae017a@google.com/
Change-Id: I16eb9f344e43a3d7d7611abf27ed7295610a2ac3
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
2025-02-13 09:25:41 +00:00
Alice Ryhl
a491945368 BACKPORT: rust: add arch_static_branch
To allow the Rust implementation of static_key_false to use runtime code
patching instead of the generic implementation, pull in the relevant
inline assembly from the jump_label.h header by running the C
preprocessor on a .rs.S file. Build rules are added for .rs.S files.

Since the relevant inline asm has been adjusted to export the inline asm
via the ARCH_STATIC_BRANCH_ASM macro in a consistent way, the Rust side
does not need architecture specific code to pull in the asm.

It is not possible to use the existing C implementation of
arch_static_branch via a Rust helper because it passes the argument
`key` to inline assembly as an 'i' parameter. Any attempt to add a C
helper for this function will fail to compile because the value of `key`
must be known at compile-time.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Alex Gaynor <alex.gaynor@gmail.com>
Cc: Wedson Almeida Filho <wedsonaf@gmail.com>
Cc: Gary Guo <gary@garyguo.net>
Cc: " =?utf-8?q?Bj=C3=B6rn_Roy_Baron?= " <bjorn3_gh@protonmail.com>
Cc: Benno Lossin <benno.lossin@proton.me>
Cc: Andreas Hindborg <a.hindborg@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Uros Bizjak <ubizjak@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Oliver Upton <oliver.upton@linux.dev>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Fuad Tabba <tabba@google.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Anup Patel <apatel@ventanamicro.com>
Cc: Andrew Jones <ajones@ventanamicro.com>
Cc: Alexandre Ghiti <alexghiti@rivosinc.com>
Cc: Conor Dooley <conor.dooley@microchip.com>
Cc: Samuel Holland <samuel.holland@sifive.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: WANG Xuerui <kernel@xen0n.name>
Cc: Bibo Mao <maobibo@loongson.cn>
Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Tianrui Zhao <zhaotianrui@loongson.cn>
Link: https://lore.kernel.org/20241030-tracepoint-v12-5-eec7f0f8ad22@google.com
Suggested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Co-developed-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

Bug: 389867843
Change-Id: I9b7ca765db8cdf0dc27b5d72989e885081f46e45
(cherry picked from commit 169484ab667788e73d1817d75c2a2c4af37dbc7f)
[ alice: fix merge conflict in rust_allowed_features ]
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
2025-01-23 23:42:02 -08:00
Alice Ryhl
5de92a7ae4 BACKPORT: rust: add tracepoint support
Make it possible to have Rust code call into tracepoints defined by C
code. It is still required that the tracepoint is declared in a C
header, and that this header is included in the input to bindgen.

Instead of calling __DO_TRACE directly, the exported rust_do_trace_
function calls an inline helper function. This is because the `cond`
argument does not exist at the callsite of DEFINE_RUST_DO_TRACE.

__DECLARE_TRACE always emits an inline static and an extern declaration
that is only used when CREATE_RUST_TRACE_POINTS is set. These should not
end up in the final binary so it is not a problem that they sometimes
are emitted without a user.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Miguel Ojeda <ojeda@kernel.org>
Cc: Alex Gaynor <alex.gaynor@gmail.com>
Cc: Wedson Almeida Filho <wedsonaf@gmail.com>
Cc: " =?utf-8?q?Bj=C3=B6rn_Roy_Baron?= " <bjorn3_gh@protonmail.com>
Cc: Benno Lossin <benno.lossin@proton.me>
Cc: Andreas Hindborg <a.hindborg@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Uros Bizjak <ubizjak@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Oliver Upton <oliver.upton@linux.dev>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Fuad Tabba <tabba@google.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Anup Patel <apatel@ventanamicro.com>
Cc: Andrew Jones <ajones@ventanamicro.com>
Cc: Alexandre Ghiti <alexghiti@rivosinc.com>
Cc: Conor Dooley <conor.dooley@microchip.com>
Cc: Samuel Holland <samuel.holland@sifive.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: WANG Xuerui <kernel@xen0n.name>
Cc: Bibo Mao <maobibo@loongson.cn>
Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Tianrui Zhao <zhaotianrui@loongson.cn>
Link: https://lore.kernel.org/20241030-tracepoint-v12-2-eec7f0f8ad22@google.com
Reviewed-by: Carlos Llamas <cmllamas@google.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

Bug: 389867843
Change-Id: Idfa07a0c5cae2e5d1554f9c30c1ec2ba9826d8fe
(cherry picked from commit ad37bcd965fda43f34cf5cc051f5d310880bd1e7)
[ alice: resolve conflict due to missing commit 0e6caab8db8b ]
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
2025-01-23 23:42:02 -08:00
Alice Ryhl
4fdd56a909 BACKPORT: rust: add static_branch_unlikely for static_key_false
Add just enough support for static key so that we can use it from
tracepoints. Tracepoints rely on `static_branch_unlikely` with a `struct
static_key_false`, so we add the same functionality to Rust.

This patch only provides a generic implementation without code patching
(matching the one used when CONFIG_JUMP_LABEL is disabled). Later
patches add support for inline asm implementations that use runtime
patching.

When CONFIG_JUMP_LABEL is unset, `static_key_count` is a static inline
function, so a Rust helper is defined for `static_key_count` in this
case. If Rust is compiled with LTO, this call should get inlined. The
helper can be eliminated once we have the necessary inline asm to make
atomic operations from Rust.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Miguel Ojeda <ojeda@kernel.org>
Cc: Alex Gaynor <alex.gaynor@gmail.com>
Cc: Wedson Almeida Filho <wedsonaf@gmail.com>
Cc: " =?utf-8?q?Bj=C3=B6rn_Roy_Baron?= " <bjorn3_gh@protonmail.com>
Cc: Benno Lossin <benno.lossin@proton.me>
Cc: Andreas Hindborg <a.hindborg@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Uros Bizjak <ubizjak@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Oliver Upton <oliver.upton@linux.dev>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Fuad Tabba <tabba@google.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Anup Patel <apatel@ventanamicro.com>
Cc: Andrew Jones <ajones@ventanamicro.com>
Cc: Alexandre Ghiti <alexghiti@rivosinc.com>
Cc: Conor Dooley <conor.dooley@microchip.com>
Cc: Samuel Holland <samuel.holland@sifive.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: WANG Xuerui <kernel@xen0n.name>
Cc: Bibo Mao <maobibo@loongson.cn>
Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Tianrui Zhao <zhaotianrui@loongson.cn>
Link: https://lore.kernel.org/20241030-tracepoint-v12-1-eec7f0f8ad22@google.com
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

Bug: 389867843
Change-Id: If13ab9143dd422d5446fef1bfa01c8ea36e8b02f
(cherry picked from commit 6e59bcc9c8adec9a5bbedfa95a89946c56c510d9)
[ alice: resolve conflict due to missing commit 4a8840af5f53 ]
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
2025-01-23 23:42:02 -08:00
Alice Ryhl
401178c45f UPSTREAM: rust: miscdevice: add base miscdevice abstraction
Provide a `MiscDevice` trait that lets you specify the file operations
that you wish to provide for your misc device. For now, only three file
operations are provided: open, close, ioctl.

These abstractions only support MISC_DYNAMIC_MINOR. This enforces that
new miscdevices should not hard-code a minor number.

When implementing ioctl, the Result type is used. This means that you
can choose to return either of:
* An integer of type isize.
* An errno using the kernel::error::Error type.
When returning an isize, the integer is returned verbatim. It's mainly
intended for returning positive integers to userspace. However, it is
technically possible to return errors via the isize return value too.

To avoid having a dependency on files, this patch does not provide the
file operations callbacks a pointer to the file. This means that they
cannot check file properties such as O_NONBLOCK (which Binder needs).
Support for that can be added as a follow-up.

To avoid having a dependency on vma, this patch does not provide any way
to implement mmap (which Binder needs). Support for that can be added as
a follow-up.

Rust Binder will use these abstractions to create the /dev/binder file
when binderfs is disabled.

Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/rust-for-linux/20240328195457.225001-1-wedsonaf@gmail.com/
Link: https://lore.kernel.org/r/20241001-b4-miscdevice-v2-2-330d760041fa@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Bug: 370906207
Change-Id: I556c00141d3ad749aac8001f493e927c4a31e304
(cherry picked from commit f893691e742688ae21ad597c5bba13bef54706cd)
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
2025-01-16 03:32:01 -08:00
Alice Ryhl
26e6ef02a3 UPSTREAM: rust: add seqfile abstraction
This adds a simple seq file abstraction that lets you print to a seq
file using ordinary Rust printing syntax.

An example user from Rust Binder:

    pub(crate) fn full_debug_print(
        &self,
        m: &SeqFile,
        owner_inner: &mut ProcessInner,
    ) -> Result<()> {
        let prio = self.node_prio();
        let inner = self.inner.access_mut(owner_inner);
        seq_print!(
            m,
            "  node {}: u{:016x} c{:016x} pri {}:{} hs {} hw {} cs {} cw {}",
            self.debug_id,
            self.ptr,
            self.cookie,
            prio.sched_policy,
            prio.prio,
            inner.strong.has_count,
            inner.weak.has_count,
            inner.strong.count,
            inner.weak.count,
        );
        if !inner.refs.is_empty() {
            seq_print!(m, " proc");
            for node_ref in &inner.refs {
                seq_print!(m, " {}", node_ref.process.task.pid());
            }
        }
        seq_print!(m, "\n");
        for t in &inner.oneway_todo {
            t.debug_print_inner(m, "    pending async transaction ");
        }
        Ok(())
    }

The `SeqFile` type is marked not thread safe so that `call_printf` can
be a `&self` method. The alternative is to use `self: Pin<&mut Self>`
which is inconvenient, or to have `SeqFile` wrap a pointer instead of
wrapping the C struct directly.

Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20241001-seqfile-v1-1-dfcd0fc21e96@google.com
Signed-off-by: Christian Brauner <brauner@kernel.org>

Bug: 370906207
(cherry picked from commit 22018a5a54a3d353bf0fee7364b2b8018ed4c5a6)
Change-Id: Ia11f76a395c2f63188215d5fde8ec79ddace92a9
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
2025-01-16 03:32:01 -08:00
Alice Ryhl
f96d52d9e6 UPSTREAM: rust: security: add abstraction for secctx
Add an abstraction for viewing the string representation of a security
context.

This is needed by Rust Binder because it has a feature where a process
can view the string representation of the security context for incoming
transactions. The process can use that to authenticate incoming
transactions, and since the feature is provided by the kernel, the
process can trust that the security context is legitimate.

This abstraction makes the following assumptions about the C side:
* When a call to `security_secid_to_secctx` is successful, it returns a
  pointer and length. The pointer references a byte string and is valid
  for reading for that many bytes.
* The string may be referenced until `security_release_secctx` is
  called.
* If CONFIG_SECURITY is set, then the three methods mentioned in
  rust/helpers are available without a helper. (That is, they are not a
  #define or `static inline`.)

Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Reviewed-by: Trevor Gross <tmgross@umich.edu>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240915-alice-file-v10-5-88484f7a3dcf@google.com
Acked-by: Paul Moore <paul@paul-moore.com>
Reviewed-by: Kees Cook <kees@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

Bug: 370906207
(cherry picked from commit 94d356c0335f95412575c4fa3954b48722359c8a)
Change-Id: Idcc8c12800b59d3d91ed63f164d0a6c82fd1a94a
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
2025-01-16 03:32:01 -08:00
Wedson Almeida Filho
e08c570f33 UPSTREAM: rust: cred: add Rust abstraction for struct cred
Add a wrapper around `struct cred` called `Credential`, and provide
functionality to get the `Credential` associated with a `File`.

Rust Binder must check the credentials of processes when they attempt to
perform various operations, and these checks usually take a
`&Credential` as parameter. The security_binder_set_context_mgr function
would be one example. This patch is necessary to access these security_*
methods from Rust.

This Rust abstraction makes the following assumptions about the C side:
* `struct cred` is refcounted with `get_cred`/`put_cred`.
* It's okay to transfer a `struct cred` across threads, that is, you do
  not need to call `put_cred` on the same thread as where you called
  `get_cred`.
* The `euid` field of a `struct cred` never changes after
  initialization.
* The `f_cred` field of a `struct file` never changes after
  initialization.

Signed-off-by: Wedson Almeida Filho <wedsonaf@gmail.com>
Co-developed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Trevor Gross <tmgross@umich.edu>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240915-alice-file-v10-4-88484f7a3dcf@google.com
Reviewed-by: Kees Cook <kees@kernel.org>
Reviewed-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>

Bug: 370906207
(cherry picked from commit a3df991d3d0648dabf761cee70bc1a1ef874db8b)
Change-Id: I3515eecddf7cd7b91d0e0d95172c2de1a7becea7
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
2025-01-16 03:32:01 -08:00
Wedson Almeida Filho
96147b1169 UPSTREAM: rust: file: add Rust abstraction for struct file
This abstraction makes it possible to manipulate the open files for a
process. The new `File` struct wraps the C `struct file`. When accessing
it using the smart pointer `ARef<File>`, the pointer will own a
reference count to the file. When accessing it as `&File`, then the
reference does not own a refcount, but the borrow checker will ensure
that the reference count does not hit zero while the `&File` is live.

Since this is intended to manipulate the open files of a process, we
introduce an `fget` constructor that corresponds to the C `fget`
method. In future patches, it will become possible to create a new fd in
a process and bind it to a `File`. Rust Binder will use these to send
fds from one process to another.

We also provide a method for accessing the file's flags. Rust Binder
will use this to access the flags of the Binder fd to check whether the
non-blocking flag is set, which affects what the Binder ioctl does.

This introduces a struct for the EBADF error type, rather than just
using the Error type directly. This has two advantages:
* `File::fget` returns a `Result<ARef<File>, BadFdError>`, which the
  compiler will represent as a single pointer, with null being an error.
  This is possible because the compiler understands that `BadFdError`
  has only one possible value, and it also understands that the
  `ARef<File>` smart pointer is guaranteed non-null.
* Additionally, we promise to users of the method that the method can
  only fail with EBADF, which means that they can rely on this promise
  without having to inspect its implementation.
That said, there are also two disadvantages:
* Defining additional error types involves boilerplate.
* The question mark operator will only utilize the `From` trait once,
  which prevents you from using the question mark operator on
  `BadFdError` in methods that return some third error type that the
  kernel `Error` is convertible into. (However, it works fine in methods
  that return `Error`.)

Signed-off-by: Wedson Almeida Filho <wedsonaf@gmail.com>
Co-developed-by: Daniel Xu <dxu@dxuuu.xyz>
Signed-off-by: Daniel Xu <dxu@dxuuu.xyz>
Co-developed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240915-alice-file-v10-3-88484f7a3dcf@google.com
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Christian Brauner <brauner@kernel.org>

Bug: 370906207
(cherry picked from commit 851849824bb5590e61048bdd3b311aadeb6a032a)
Change-Id: I6ee12e50e6396317fa76674d39557e9018df523c
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
2025-01-16 03:32:01 -08:00
Gary Guo
e18d5b4248 rust: enable arbitrary_self_types and remove Receiver
commit c95bbb59a9b22f9b838b15d28319185c1c884329 upstream.

The term "receiver" means that a type can be used as the type of `self`,
and thus enables method call syntax `foo.bar()` instead of
`Foo::bar(foo)`. Stable Rust as of today (1.81) enables a limited
selection of types (primitives and types in std, e.g. `Box` and `Arc`)
to be used as receivers, while custom types cannot.

We want the kernel `Arc` type to have the same functionality as the Rust
std `Arc`, so we use the `Receiver` trait (gated behind `receiver_trait`
unstable feature) to gain the functionality.

The `arbitrary_self_types` RFC [1] (tracking issue [2]) is accepted and
it will allow all types that implement a new `Receiver` trait (different
from today's unstable trait) to be used as receivers. This trait will be
automatically implemented for all `Deref` types, which include our `Arc`
type, so we no longer have to opt-in to be used as receiver. To prepare
us for the change, remove the `Receiver` implementation and the
associated feature. To still allow `Arc` and others to be used as method
receivers, turn on `arbitrary_self_types` feature instead.

This feature gate is introduced in 1.23.0. It used to enable both
`Deref` types and raw pointer types to be used as receivers, but the
latter is now split into a different feature gate in Rust 1.83 nightly.
We do not need receivers on raw pointers so this change would not affect
us and usage of `arbitrary_self_types` feature would work for all Rust
versions that we support (>=1.78).

Cc: Adrian Taylor <ade@hohum.me.uk>
Link: https://github.com/rust-lang/rfcs/pull/3519 [1]
Link: https://github.com/rust-lang/rust/issues/44874 [2]
Signed-off-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240915132734.1653004-1-gary@garyguo.net
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-14 20:03:34 +01:00
Yutaro Ohno
b26e36b3e2 rust: kernel: fix THIS_MODULE header path in ThisModule doc comment
[ Upstream commit 8b55dc8610acf816a66373be53ca6e3bbe2d313a ]

The doc comment for `ThisModule` incorrectly states the C header file
for `THIS_MODULE` as `include/linux/export.h`, while the correct path is
`include/linux/init.h`. This is because `THIS_MODULE` was moved in
commit 5b20755b77 ("init: move THIS_MODULE from <linux/export.h> to
<linux/init.h>").

Update the doc comment for `ThisModule` to reflect the correct header
file path for `THIS_MODULE`.

Fixes: 5b20755b77 ("init: move THIS_MODULE from <linux/export.h> to <linux/init.h>")
Signed-off-by: Yutaro Ohno <yutaro.ono.418@gmail.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/ZxXDZwxWgoEiIYkj@ohnotp
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-05 14:02:20 +01:00
Miguel Ojeda
ece207a83e rust: kernel: sort Rust modules
Rust modules are intended to be sorted, thus do so.

This makes `rustfmtcheck` to pass again.

Fixes: 5701725692 ("Merge tag 'rust-6.12' of https://github.com/Rust-for-Linux/linux")
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240926124751.345471-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-09-26 17:49:00 +02:00
Linus Torvalds
5701725692 Merge tag 'rust-6.12' of https://github.com/Rust-for-Linux/linux
Pull Rust updates from Miguel Ojeda:
 "Toolchain and infrastructure:

   - Support 'MITIGATION_{RETHUNK,RETPOLINE,SLS}' (which cleans up
     objtool warnings), teach objtool about 'noreturn' Rust symbols and
     mimic '___ADDRESSABLE()' for 'module_{init,exit}'. With that, we
     should be objtool-warning-free, so enable it to run for all Rust
     object files.

   - KASAN (no 'SW_TAGS'), KCFI and shadow call sanitizer support.

   - Support 'RUSTC_VERSION', including re-config and re-build on
     change.

   - Split helpers file into several files in a folder, to avoid
     conflicts in it. Eventually those files will be moved to the right
     places with the new build system. In addition, remove the need to
     manually export the symbols defined there, reusing existing
     machinery for that.

   - Relax restriction on configurations with Rust + GCC plugins to just
     the RANDSTRUCT plugin.

  'kernel' crate:

   - New 'list' module: doubly-linked linked list for use with reference
     counted values, which is heavily used by the upcoming Rust Binder.

     This includes 'ListArc' (a wrapper around 'Arc' that is guaranteed
     unique for the given ID), 'AtomicTracker' (tracks whether a
     'ListArc' exists using an atomic), 'ListLinks' (the prev/next
     pointers for an item in a linked list), 'List' (the linked list
     itself), 'Iter' (an iterator over a 'List'), 'Cursor' (a cursor
     into a 'List' that allows to remove elements), 'ListArcField' (a
     field exclusively owned by a 'ListArc'), as well as support for
     heterogeneous lists.

   - New 'rbtree' module: red-black tree abstractions used by the
     upcoming Rust Binder.

     This includes 'RBTree' (the red-black tree itself), 'RBTreeNode' (a
     node), 'RBTreeNodeReservation' (a memory reservation for a node),
     'Iter' and 'IterMut' (immutable and mutable iterators), 'Cursor'
     (bidirectional cursor that allows to remove elements), as well as
     an entry API similar to the Rust standard library one.

   - 'init' module: add 'write_[pin_]init' methods and the
     'InPlaceWrite' trait. Add the 'assert_pinned!' macro.

   - 'sync' module: implement the 'InPlaceInit' trait for 'Arc' by
     introducing an associated type in the trait.

   - 'alloc' module: add 'drop_contents' method to 'BoxExt'.

   - 'types' module: implement the 'ForeignOwnable' trait for
     'Pin<Box<T>>' and improve the trait's documentation. In addition,
     add the 'into_raw' method to the 'ARef' type.

   - 'error' module: in preparation for the upcoming Rust support for
     32-bit architectures, like arm, locally allow Clippy lint for
     those.

  Documentation:

   - https://rust.docs.kernel.org has been announced, so link to it.

   - Enable rustdoc's "jump to definition" feature, making its output a
     bit closer to the experience in a cross-referencer.

   - Debian Testing now also provides recent Rust releases (outside of
     the freeze period), so add it to the list.

  MAINTAINERS:

   - Trevor is joining as reviewer of the "RUST" entry.

  And a few other small bits"

* tag 'rust-6.12' of https://github.com/Rust-for-Linux/linux: (54 commits)
  kasan: rust: Add KASAN smoke test via UAF
  kbuild: rust: Enable KASAN support
  rust: kasan: Rust does not support KHWASAN
  kbuild: rust: Define probing macros for rustc
  kasan: simplify and clarify Makefile
  rust: cfi: add support for CFI_CLANG with Rust
  cfi: add CONFIG_CFI_ICALL_NORMALIZE_INTEGERS
  rust: support for shadow call stack sanitizer
  docs: rust: include other expressions in conditional compilation section
  kbuild: rust: replace proc macros dependency on `core.o` with the version text
  kbuild: rust: rebuild if the version text changes
  kbuild: rust: re-run Kconfig if the version text changes
  kbuild: rust: add `CONFIG_RUSTC_VERSION`
  rust: avoid `box_uninit_write` feature
  MAINTAINERS: add Trevor Gross as Rust reviewer
  rust: rbtree: add `RBTree::entry`
  rust: rbtree: add cursor
  rust: rbtree: add mutable iterator
  rust: rbtree: add iterator
  rust: rbtree: add red-black tree implementation backed by the C version
  ...
2024-09-25 10:25:40 -07:00
Wedson Almeida Filho
a0d13aac70 rust: rbtree: add red-black tree implementation backed by the C version
The rust rbtree exposes a map-like interface over keys and values,
backed by the kernel red-black tree implementation. Values can be
inserted, deleted, and retrieved from a `RBTree` by key.

This base abstraction is used by binder to store key/value
pairs and perform lookups, for example the patch
"[PATCH RFC 03/20] rust_binder: add threading support"
in the binder RFC [1].

Link: https://lore.kernel.org/rust-for-linux/20231101-rust-binder-v1-3-08ba9197f637@google.com/ [1]
Signed-off-by: Wedson Almeida Filho <wedsonaf@gmail.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Tested-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Signed-off-by: Matt Gilbride <mattgilbride@google.com>
Link: https://lore.kernel.org/r/20240822-b4-rbtree-v12-1-014561758a57@google.com
[ Updated link to docs.kernel.org. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-08-31 17:35:08 +02:00
FUJITA Tomonori
4d080a029d rust: sizes: add commonly used constants
Add rust equivalent to include/linux/sizes.h, makes code more
readable. Only SZ_*K that QT2025 PHY driver uses are added.

Make generated constants accessible with a proper type.

Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Trevor Gross <tmgross@umich.edu>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2024-08-30 10:27:34 +01:00
Alice Ryhl
6cd3417155 rust: list: add ListArc
The `ListArc` type can be thought of as a special reference to a
refcounted object that owns the permission to manipulate the
`next`/`prev` pointers stored in the refcounted object. By ensuring that
each object has only one `ListArc` reference, the owner of that
reference is assured exclusive access to the `next`/`prev` pointers.
When a `ListArc` is inserted into a `List`, the `List` takes ownership
of the `ListArc` reference.

There are various strategies for ensuring that a value has only one
`ListArc` reference. The simplest is to convert a `UniqueArc` into a
`ListArc`. However, the refcounted object could also keep track of
whether a `ListArc` exists using a boolean, which could allow for the
creation of new `ListArc` references from an `Arc` reference. Whatever
strategy is used, the relevant tracking is referred to as "the tracking
inside `T`", and the `ListArcSafe` trait (and its subtraits) are used to
update the tracking when a `ListArc` is created or destroyed.

Note that we allow the case where the tracking inside `T` thinks that a
`ListArc` exists, but actually, there isn't a `ListArc`. However, we do
not allow the opposite situation where a `ListArc` exists, but the
tracking thinks it doesn't. This is because the former can at most
result in us failing to create a `ListArc` when the operation could
succeed, whereas the latter can result in the creation of two `ListArc`
references. Only the latter situation can lead to memory safety issues.

This patch introduces the `impl_list_arc_safe!` macro that allows you to
implement `ListArcSafe` for types using the strategy where a `ListArc`
can only be created from a `UniqueArc`. Other strategies are introduced
in later patches.

This is part of the linked list that Rust Binder will use for many
different things. The strategy where a `ListArc` can only be created
from a `UniqueArc` is actually sufficient for most of the objects that
Rust Binder needs to insert into linked lists. Usually, these are todo
items that are created and then immediately inserted into a queue.

The const generic ID allows objects to have several prev/next pointer
pairs so that the same object can be inserted into several different
lists. You are able to have several `ListArc` references as long as they
correspond to different pointer pairs. The ID itself is purely a
compile-time concept and will not be present in the final binary. Both
the `List` and the `ListArc` will need to agree on the ID for them to
work together. Rust Binder uses this in a few places (e.g. death
recipients) where the same object can be inserted into both generic todo
lists and some other lists for tracking the status of the object.

The ID is a const generic rather than a type parameter because the
`pair_from_unique` method needs to be able to assert that the two ids
are different. There's no easy way to assert that when using types
instead of integers.

Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240814-linked-list-v5-2-f5f5e8075da0@google.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-08-23 06:26:57 +02:00
Linus Torvalds
910bfc26d1 Merge tag 'rust-6.11' of https://github.com/Rust-for-Linux/linux
Pull Rust updates from Miguel Ojeda:
 "The highlight is the establishment of a minimum version for the Rust
  toolchain, including 'rustc' (and bundled tools) and 'bindgen'.

  The initial minimum will be the pinned version we currently have, i.e.
  we are just widening the allowed versions. That covers three stable
  Rust releases: 1.78.0, 1.79.0, 1.80.0 (getting released tomorrow),
  plus beta, plus nightly.

  This should already be enough for kernel developers in distributions
  that provide recent Rust compiler versions routinely, such as Arch
  Linux, Debian Unstable (outside the freeze period), Fedora Linux,
  Gentoo Linux (especially the testing channel), Nix (unstable) and
  openSUSE Slowroll and Tumbleweed.

  In addition, the kernel is now being built-tested by Rust's pre-merge
  CI. That is, every change that is attempting to land into the Rust
  compiler is tested against the kernel, and it is merged only if it
  passes. Similarly, the bindgen tool has agreed to build the kernel in
  their CI too.

  Thus, with the pre-merge CI in place, both projects hope to avoid
  unintentional changes to Rust that break the kernel. This means that,
  in general, apart from intentional changes on their side (that we will
  need to workaround conditionally on our side), the upcoming Rust
  compiler versions should generally work.

  In addition, the Rust project has proposed getting the kernel into
  stable Rust (at least solving the main blockers) as one of its three
  flagship goals for 2024H2 [1].

  I would like to thank Niko, Sid, Emilio et al. for their help
  promoting the collaboration between Rust and the kernel.

  Toolchain and infrastructure:

   - Support several Rust toolchain versions.

   - Support several bindgen versions.

   - Remove 'cargo' requirement and simplify 'rusttest', thanks to
     'alloc' having been dropped last cycle.

   - Provide proper error reporting for the 'rust-analyzer' target.

  'kernel' crate:

   - Add 'uaccess' module with a safe userspace pointers abstraction.

   - Add 'page' module with a 'struct page' abstraction.

   - Support more complex generics in workqueue's 'impl_has_work!'
     macro.

  'macros' crate:

   - Add 'firmware' field support to the 'module!' macro.

   - Improve 'module!' macro documentation.

  Documentation:

   - Provide instructions on what packages should be installed to build
     the kernel in some popular Linux distributions.

   - Introduce the new kernel.org LLVM+Rust toolchains.

   - Explain '#[no_std]'.

  And a few other small bits"

Link: https://rust-lang.github.io/rust-project-goals/2024h2/index.html#flagship-goals [1]

* tag 'rust-6.11' of https://github.com/Rust-for-Linux/linux: (26 commits)
  docs: rust: quick-start: add section on Linux distributions
  rust: warn about `bindgen` versions 0.66.0 and 0.66.1
  rust: start supporting several `bindgen` versions
  rust: work around `bindgen` 0.69.0 issue
  rust: avoid assuming a particular `bindgen` build
  rust: start supporting several compiler versions
  rust: simplify Clippy warning flags set
  rust: relax most deny-level lints to warnings
  rust: allow `dead_code` for never constructed bindings
  rust: init: simplify from `map_err` to `inspect_err`
  rust: macros: indent list item in `paste!`'s docs
  rust: add abstraction for `struct page`
  rust: uaccess: add typed accessors for userspace pointers
  uaccess: always export _copy_[from|to]_user with CONFIG_RUST
  rust: uaccess: add userspace pointers
  kbuild: rust-analyzer: improve comment documentation
  kbuild: rust-analyzer: better error handling
  docs: rust: no_std is used
  rust: alloc: add __GFP_HIGHMEM flag
  rust: alloc: fix typo in docs for GFP_NOWAIT
  ...
2024-07-27 13:44:54 -07:00
Linus Torvalds
c2a96b7f18 Merge tag 'driver-core-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH:
 "Here is the big set of driver core changes for 6.11-rc1.

  Lots of stuff in here, with not a huge diffstat, but apis are evolving
  which required lots of files to be touched. Highlights of the changes
  in here are:

   - platform remove callback api final fixups (Uwe took many releases
     to get here, finally!)

   - Rust bindings for basic firmware apis and initial driver-core
     interactions.

     It's not all that useful for a "write a whole driver in rust" type
     of thing, but the firmware bindings do help out the phy rust
     drivers, and the driver core bindings give a solid base on which
     others can start their work.

     There is still a long way to go here before we have a multitude of
     rust drivers being added, but it's a great first step.

   - driver core const api changes.

     This reached across all bus types, and there are some fix-ups for
     some not-common bus types that linux-next and 0-day testing shook
     out.

     This work is being done to help make the rust bindings more safe,
     as well as the C code, moving toward the end-goal of allowing us to
     put driver structures into read-only memory. We aren't there yet,
     but are getting closer.

   - minor devres cleanups and fixes found by code inspection

   - arch_topology minor changes

   - other minor driver core cleanups

  All of these have been in linux-next for a very long time with no
  reported problems"

* tag 'driver-core-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (55 commits)
  ARM: sa1100: make match function take a const pointer
  sysfs/cpu: Make crash_hotplug attribute world-readable
  dio: Have dio_bus_match() callback take a const *
  zorro: make match function take a const pointer
  driver core: module: make module_[add|remove]_driver take a const *
  driver core: make driver_find_device() take a const *
  driver core: make driver_[create|remove]_file take a const *
  firmware_loader: fix soundness issue in `request_internal`
  firmware_loader: annotate doctests as `no_run`
  devres: Correct code style for functions that return a pointer type
  devres: Initialize an uninitialized struct member
  devres: Fix memory leakage caused by driver API devm_free_percpu()
  devres: Fix devm_krealloc() wasting memory
  driver core: platform: Switch to use kmemdup_array()
  driver core: have match() callback in struct bus_type take a const *
  MAINTAINERS: add Rust device abstractions to DRIVER CORE
  device: rust: improve safety comments
  MAINTAINERS: add Danilo as FIRMWARE LOADER maintainer
  MAINTAINERS: add Rust FW abstractions to FIRMWARE LOADER
  firmware: rust: improve safety comments
  ...
2024-07-25 10:42:22 -07:00
Alice Ryhl
fc6e66f469 rust: add abstraction for struct page
Adds a new struct called `Page` that wraps a pointer to `struct page`.
This struct is assumed to hold ownership over the page, so that Rust
code can allocate and manage pages directly.

The page type has various methods for reading and writing into the page.
These methods will temporarily map the page to allow the operation. All
of these methods use a helper that takes an offset and length, performs
bounds checks, and returns a pointer to the given offset in the page.

This patch only adds support for pages of order zero, as that is all
Rust Binder needs. However, it is written to make it easy to add support
for higher-order pages in the future. To do that, you would add a const
generic parameter to `Page` that specifies the order. Most of the
methods do not need to be adjusted, as the logic for dealing with
mapping multiple pages at once can be isolated to just the
`with_pointer_into_page` method.

Rust Binder needs to manage pages directly as that is how transactions
are delivered: Each process has an mmap'd region for incoming
transactions. When an incoming transaction arrives, the Binder driver
will choose a region in the mmap, allocate and map the relevant pages
manually, and copy the incoming transaction directly into the page. This
architecture allows the driver to copy transactions directly from the
address space of one process to another, without an intermediate copy
to a kernel buffer.

This code is based on Wedson's page abstractions from the old rust
branch, but it has been modified by Alice by removing the incomplete
support for higher-order pages, by introducing the `with_*` helpers
to consolidate the bounds checking logic into a single place, and
various other changes.

Co-developed-by: Wedson Almeida Filho <wedsonaf@gmail.com>
Signed-off-by: Wedson Almeida Filho <wedsonaf@gmail.com>
Reviewed-by: Andreas Hindborg <a.hindborg@samsung.com>
Reviewed-by: Trevor Gross <tmgross@umich.edu>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240528-alice-mm-v7-4-78222c31b8f4@google.com
[ Fixed typos and added a few intra-doc links. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-07-08 23:44:01 +02:00
Wedson Almeida Filho
1b580e7b9b rust: uaccess: add userspace pointers
A pointer to an area in userspace memory, which can be either read-only
or read-write.

All methods on this struct are safe: attempting to read or write on bad
addresses (either out of the bound of the slice or unmapped addresses)
will return `EFAULT`. Concurrent access, *including data races to/from
userspace memory*, is permitted, because fundamentally another userspace
thread/process could always be modifying memory at the same time (in the
same way that userspace Rust's `std::io` permits data races with the
contents of files on disk). In the presence of a race, the exact byte
values read/written are unspecified but the operation is well-defined.
Kernelspace code should validate its copy of data after completing a
read, and not expect that multiple reads of the same address will return
the same value.

These APIs are designed to make it difficult to accidentally write
TOCTOU bugs. Every time you read from a memory location, the pointer is
advanced by the length so that you cannot use that reader to read the
same memory location twice. Preventing double-fetches avoids TOCTOU
bugs. This is accomplished by taking `self` by value to prevent
obtaining multiple readers on a given `UserSlice`, and the readers only
permitting forward reads. If double-fetching a memory location is
necessary for some reason, then that is done by creating multiple
readers to the same memory location.

Constructing a `UserSlice` performs no checks on the provided address
and length, it can safely be constructed inside a kernel thread with no
current userspace process. Reads and writes wrap the kernel APIs
`copy_from_user` and `copy_to_user`, which check the memory map of the
current process and enforce that the address range is within the user
range (no additional calls to `access_ok` are needed).

This code is based on something that was originally written by Wedson on
the old rust branch. It was modified by Alice by removing the
`IoBufferReader` and `IoBufferWriter` traits, and various other changes.

Signed-off-by: Wedson Almeida Filho <wedsonaf@gmail.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Trevor Gross <tmgross@umich.edu>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Co-developed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240528-alice-mm-v7-1-78222c31b8f4@google.com
[ Wrapped docs to 100 and added a few intra-doc links. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-07-08 23:44:01 +02:00
Danilo Krummrich
de6582833d rust: add firmware abstractions
Add an abstraction around the kernels firmware API to request firmware
images. The abstraction provides functions to access the firmware's size
and backing buffer.

The firmware is released once the abstraction instance is dropped.

Signed-off-by: Danilo Krummrich <dakr@redhat.com>
Acked-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://lore.kernel.org/r/20240618154841.6716-3-dakr@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-18 18:45:12 +02:00
Danilo Krummrich
a674fefd17 rust: add abstraction for struct device
Add an (always) reference-counted abstraction for a generic C `struct
device`. This abstraction encapsulates existing `struct device` instances
and manages its reference count.

Subsystems may use this abstraction as a base to abstract subsystem
specific device instances based on a generic `struct device`, such as
`struct pci_dev`.

Co-developed-by: Wedson Almeida Filho <wedsonaf@gmail.com>
Signed-off-by: Wedson Almeida Filho <wedsonaf@gmail.com>
Signed-off-by: Danilo Krummrich <dakr@redhat.com>
Link: https://lore.kernel.org/r/20240618154841.6716-2-dakr@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-18 18:45:06 +02:00
Andreas Hindborg
3253aba340 rust: block: introduce kernel::block::mq module
Add initial abstractions for working with blk-mq.

This patch is a maintained, refactored subset of code originally published
by Wedson Almeida Filho <wedsonaf@gmail.com> [1].

[1] f2cfd2fe0e/rust/kernel/blk/mq.rs

Cc: Wedson Almeida Filho <wedsonaf@gmail.com>
Signed-off-by: Andreas Hindborg <a.hindborg@samsung.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20240611114551.228679-2-nmi@metaspace.dk
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-06-14 07:45:04 -06:00
Linus Torvalds
8f5b5f7811 Merge tag 'rust-6.10' of https://github.com/Rust-for-Linux/linux
Pull Rust updates from Miguel Ojeda:
 "The most notable change is the drop of the 'alloc' in-tree fork. This
  is nicely reflected in the diffstat as a ~10k lines drop. In turn,
  this makes the version upgrades way simpler and smaller in the future,
  e.g. the latest one in commit 56f64b3706 ("rust: upgrade to Rust
  1.78.0").

  More importantly, this increases the chances that a newer compiler
  version just works, which in turn means supporting several compiler
  versions is easier now. Thus we will look into finally setting a
  minimum version in the near future.

  Toolchain and infrastructure:

   - Upgrade to Rust 1.78.0

     This time around, due to how the kernel and Rust schedules have
     aligned, there are two upgrades in fact. These allow us to remove
     one more unstable feature ('offset_of') from the list, among other
     improvements

   - Drop 'alloc' in-tree fork of the standard library crate, which
     means all the unstable features used by 'alloc' (~30 language ones,
     ~60 library ones) are not a concern anymore

   - Support DWARFv5 via the '-Zdwarf-version' flag

   - Support zlib and zstd debuginfo compression via the
     '-Zdebuginfo-compression' flag

  'kernel' crate:

   - Support allocation flags ('GFP_*'), particularly in 'Box' (via
     'BoxExt'), 'Vec' (via 'VecExt'), 'Arc' and 'UniqueArc', as well as
     in the 'init' module APIs

   - Remove usage of the 'allocator_api' unstable feature

   - Remove 'try_' prefix in allocation APIs' names

   - Add 'VecExt' (an extension trait) to be able to drop the 'alloc'
     fork

   - Add the '{make,to}_{upper,lower}case()' methods to 'CStr'/'CString'

   - Add the 'as_ptr' method to 'ThisModule'

   - Add the 'from_raw' method to 'ArcBorrow'

   - Add the 'into_unique_or_drop' method to 'Arc'

   - Display column number in the 'dbg!' macro output by applying the
     equivalent change done to the standard library one

   - Migrate 'Work' to '#[pin_data]' thanks to the changes in the
     'macros' crate, which allows to remove an unsafe call in its 'new'
     associated function

   - Prevent namespacing issues when using the '[try_][pin_]init!'
     macros by changing the generated name of guard variables

   - Make the 'get' method in 'Opaque' const

   - Implement the 'Default' trait for 'LockClassKey'

   - Remove unneeded 'kernel::prelude' imports from doctests

   - Remove redundant imports

  'macros' crate:

   - Add 'decl_generics' to 'parse_generics()' to support default
     values, and use that to allow them in '#[pin_data]'

  Helpers:

   - Trivial English grammar fix

  Documentation:

   - Add section on Rust Kselftests to the 'Testing' document

   - Expand the 'Abstractions vs. bindings' section of the 'General
     Information' document"

* tag 'rust-6.10' of https://github.com/Rust-for-Linux/linux: (31 commits)
  rust: alloc: fix dangling pointer in VecExt<T>::reserve()
  rust: upgrade to Rust 1.78.0
  rust: kernel: remove redundant imports
  rust: sync: implement `Default` for `LockClassKey`
  docs: rust: extend abstraction and binding documentation
  docs: rust: Add instructions for the Rust kselftest
  rust: remove unneeded `kernel::prelude` imports from doctests
  rust: update `dbg!()` to format column number
  rust: helpers: Fix grammar in comment
  rust: init: change the generated name of guard variables
  rust: sync: add `Arc::into_unique_or_drop`
  rust: sync: add `ArcBorrow::from_raw`
  rust: types: Make Opaque::get const
  rust: kernel: remove usage of `allocator_api` unstable feature
  rust: init: update `init` module to take allocation flags
  rust: sync: update `Arc` and `UniqueArc` to take allocation flags
  rust: alloc: update `VecExt` to take allocation flags
  rust: alloc: introduce the `BoxExt` trait
  rust: alloc: introduce allocation flags
  rust: alloc: remove our fork of the `alloc` crate
  ...
2024-05-13 15:13:54 -07:00
Wedson Almeida Filho
323617f649 rust: kernel: require Send for Module implementations
The thread that calls the module initialisation code when a module is
loaded is not guaranteed [in fact, it is unlikely] to be the same one
that calls the module cleanup code on module unload, therefore, `Module`
implementations must be `Send` to account for them moving from one
thread to another implicitly.

Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Cc: stable@vger.kernel.org # 6.8.x: df70d04d56: rust: phy: implement `Send` for `Registration`
Cc: stable@vger.kernel.org
Fixes: 247b365dc8 ("rust: add `kernel` crate")
Link: https://lore.kernel.org/r/20240328195457.225001-3-wedsonaf@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-04-23 00:38:43 +02:00
Wedson Almeida Filho
2c1092853f rust: kernel: remove usage of allocator_api unstable feature
With the adoption of `BoxExt` and `VecExt`, we don't need the functions
provided by this feature (namely the methods prefixed with `try_` and
different allocator per collection instance).

We do need `AllocError`, but we define our own as it is a trivial empty
struct.

Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com>
Link: https://lore.kernel.org/r/20240328013603.206764-11-wedsonaf@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-04-16 22:50:04 +02:00
Wedson Almeida Filho
5ab560ce12 rust: alloc: update VecExt to take allocation flags
We also rename the methods by removing the `try_` prefix since the names
are available due to our usage of the `no_global_oom_handling` config
when building the `alloc` crate.

Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20240328013603.206764-8-wedsonaf@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-04-16 22:50:04 +02:00
Wedson Almeida Filho
03989773a9 rust: alloc: introduce the VecExt trait
Make `try_with_capacity`, `try_push`, and `try_extend_from_slice`
methods available in `Vec` even though it doesn't implement them. It is
implemented with `try_reserve` and `push_within_capacity`.

This is in preparation for switching to the upstream `alloc` crate.

Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Suggested-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com>
Link: https://lore.kernel.org/r/20240328013603.206764-3-wedsonaf@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-04-16 22:03:14 +02:00
Wedson Almeida Filho
31d94d8f58 rust: kernel: move allocator module under alloc
We will add more to the `alloc` module in subsequent patches (e.g.,
allocation flags and extension traits).

Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com>
Link: https://lore.kernel.org/r/20240328013603.206764-2-wedsonaf@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-04-16 22:03:14 +02:00
Miguel Ojeda
b481dd85f5 rust: upgrade to Rust 1.77.1
This is the next upgrade to the Rust toolchain, from 1.76.0 to 1.77.1
(i.e. the latest) [1].

See the upgrade policy [2] and the comments on the first upgrade in
commit 3ed03f4da0 ("rust: upgrade to Rust 1.68.2").

# Unstable features

The `offset_of` feature (single-field `offset_of!`) that we were using
got stabilized in Rust 1.77.0 [3].

Therefore, now the only unstable features allowed to be used outside the
`kernel` crate is `new_uninit`, though other code to be upstreamed may
increase the list.

Please see [4] for details.

# Required changes

Rust 1.77.0 merged the `unused_tuple_struct_fields` lint into `dead_code`,
thus upgrading it from `allow` to `warn` [5]. In turn, this made `rustc`
complain about the `ThisModule`'s pointer field being never read, but
the previous patch adds the `as_ptr` method to it, needed by Binder [6],
so that we do not need to locally `allow` it.

# Other changes

Rust 1.77.0 introduces the `--check-cfg` feature [7], for which there
is a Call for Testing going on [8]. We were requested to test it and
we found it useful [9] -- we will likely enable it in the future.

# `alloc` upgrade and reviewing

The vast majority of changes are due to our `alloc` fork being upgraded
at once.

There are two kinds of changes to be aware of: the ones coming from
upstream, which we should follow as closely as possible, and the updates
needed in our added fallible APIs to keep them matching the newer
infallible APIs coming from upstream.

Instead of taking a look at the diff of this patch, an alternative
approach is reviewing a diff of the changes between upstream `alloc` and
the kernel's. This allows to easily inspect the kernel additions only,
especially to check if the fallible methods we already have still match
the infallible ones in the new version coming from upstream.

Another approach is reviewing the changes introduced in the additions in
the kernel fork between the two versions. This is useful to spot
potentially unintended changes to our additions.

To apply these approaches, one may follow steps similar to the following
to generate a pair of patches that show the differences between upstream
Rust and the kernel (for the subset of `alloc` we use) before and after
applying this patch:

    # Get the difference with respect to the old version.
    git -C rust checkout $(linux/scripts/min-tool-version.sh rustc)
    git -C linux ls-tree -r --name-only HEAD -- rust/alloc |
        cut -d/ -f3- |
        grep -Fv README.md |
        xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH
    git -C linux diff --patch-with-stat --summary -R > old.patch
    git -C linux restore rust/alloc

    # Apply this patch.
    git -C linux am rust-upgrade.patch

    # Get the difference with respect to the new version.
    git -C rust checkout $(linux/scripts/min-tool-version.sh rustc)
    git -C linux ls-tree -r --name-only HEAD -- rust/alloc |
        cut -d/ -f3- |
        grep -Fv README.md |
        xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH
    git -C linux diff --patch-with-stat --summary -R > new.patch
    git -C linux restore rust/alloc

Now one may check the `new.patch` to take a look at the additions (first
approach) or at the difference between those two patches (second
approach). For the latter, a side-by-side tool is recommended.

Link: https://github.com/rust-lang/rust/blob/stable/RELEASES.md#version-1770-2024-03-21 [1]
Link: https://rust-for-linux.com/rust-version-policy [2]
Link: https://github.com/rust-lang/rust/pull/118799 [3]
Link: https://github.com/Rust-for-Linux/linux/issues/2 [4]
Link: https://github.com/rust-lang/rust/pull/118297 [5]
Link: https://lore.kernel.org/rust-for-linux/20231101-rust-binder-v1-2-08ba9197f637@google.com/#Z31rust:kernel:lib.rs [6]
Link: https://doc.rust-lang.org/nightly/unstable-book/compiler-flags/check-cfg.html [7]
Link: https://github.com/rust-lang/rfcs/pull/3013#issuecomment-1936648479 [8]
Link: https://github.com/rust-lang/rust/issues/82450#issuecomment-1947462977 [9]
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Tested-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://lore.kernel.org/r/20240217002717.57507-1-ojeda@kernel.org
[ Upgraded to 1.77.1. Removed `allow(dead_code)` thanks to the previous
  patch. Reworded accordingly. No changes to `alloc` during the beta. ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-03-29 20:12:30 +01:00
Alice Ryhl
d0f0241d8d rust: add Module::as_ptr
This allows you to get a raw pointer to THIS_MODULE for use in unsafe
code. The Rust Binder RFC uses it when defining fops for the binderfs
component [1].

This doesn't really need to go in now - it could go in together with
Rust Binder like how it is sent in the Rust Binder RFC. However, the
upcoming 1.77.0 release of the Rust compiler introduces a new warning,
and applying this patch now will silence that warning. That allows us to
avoid adding the #[allow(dead_code)] annotation seen in [2].

Link: https://lore.kernel.org/rust-for-linux/20231101-rust-binder-v1-2-08ba9197f637@google.com/ [1]
Link: https://lore.kernel.org/all/20240217002717.57507-1-ojeda@kernel.org/ [2]
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Trevor Gross <tmgross@umich.edu>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20240226-module-as-ptr-v1-1-83bc89213113@google.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-03-29 18:04:32 +01:00
Wedson Almeida Filho
e944171070 rust: add container_of! macro
This macro is used to obtain a pointer to an entire struct
when given a pointer to a field in that struct.

Signed-off-by: Wedson Almeida Filho <wedsonaf@gmail.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Tested-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Matt Gilbride <mattgilbride@google.com>
Link: https://lore.kernel.org/r/20240219-b4-rbtree-v2-1-0b113aab330d@google.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-02-25 19:17:31 +01:00
Alice Ryhl
44f2e626cb rust: kernel: stop using ptr_metadata feature
The `byte_sub` method was stabilized in Rust 1.75.0. By using that
method, we no longer need the unstable `ptr_metadata` feature for
implementing `Arc::from_raw`.

This brings us one step closer towards not using unstable compiler
features.

Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Reviewed-by: Trevor Gross <tmgross@umich.edu>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240215104601.1267763-1-aliceryhl@google.com
[ Reworded title. ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-02-18 21:22:27 +01:00
Valentin Obst
ed8596532a rust: kernel: add srctree-relative doclinks
Convert existing references to C header files to make use of
Commit bc2e7d5c29 ("rust: support `srctree`-relative links").

Signed-off-by: Valentin Obst <kernel@valentinobst.de>
Reviewed-by: Trevor Gross <tmgross@umich.edu>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240131-doc-fixes-v3-v3-4-0c8af94ed7de@valentinobst.de
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-02-18 21:22:27 +01:00
Alice Ryhl
82e1708748 rust: time: add msecs to jiffies conversion
Defines type aliases and conversions for msecs and jiffies.

This is used by Rust Binder for process freezing. There, we want to
sleep until the freeze operation completes, but we want to be able to
abort the process freezing if it doesn't complete within some timeout.
The freeze timeout is supplied in msecs.

Note that we need to convert to jiffies in Binder. It is not enough to
introduce a variant of `CondVar::wait_timeout` that takes the timeout in
msecs because we need to be able to restart the sleep with the remaining
sleep duration if it is interrupted, and if the API takes msecs rather
than jiffies, then that would require a conversion roundtrip jiffies->
msecs->jiffies that is best avoided.

Suggested-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Reviewed-by: Tiago Lam <tiagolam@gmail.com>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240108-rb-new-condvar-methods-v4-2-88e0c871cc05@google.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-01-28 19:50:48 +01:00
Miguel Ojeda
c5fed8ce65 rust: upgrade to Rust 1.75.0
This is the next upgrade to the Rust toolchain, from 1.74.1 to 1.75.0
(i.e. the latest) [1].

See the upgrade policy [2] and the comments on the first upgrade in
commit 3ed03f4da0 ("rust: upgrade to Rust 1.68.2").

# Unstable features

The `const_maybe_uninit_zeroed` unstable feature [3] was stabilized in
Rust 1.75.0, which we were using in the PHYLIB abstractions.

The only unstable features allowed to be used outside the `kernel` crate
are still `new_uninit,offset_of`, though other code to be upstreamed
may increase the list.

Please see [4] for details.

# Other improvements

Rust 1.75.0 stabilized `pointer_byte_offsets` [5] which we could
potentially use as an alternative for `ptr_metadata` in the future.

# Required changes

For this upgrade, no changes were required (i.e. on our side).

# `alloc` upgrade and reviewing

The vast majority of changes are due to our `alloc` fork being upgraded
at once.

There are two kinds of changes to be aware of: the ones coming from
upstream, which we should follow as closely as possible, and the updates
needed in our added fallible APIs to keep them matching the newer
infallible APIs coming from upstream.

Instead of taking a look at the diff of this patch, an alternative
approach is reviewing a diff of the changes between upstream `alloc` and
the kernel's. This allows to easily inspect the kernel additions only,
especially to check if the fallible methods we already have still match
the infallible ones in the new version coming from upstream.

Another approach is reviewing the changes introduced in the additions in
the kernel fork between the two versions. This is useful to spot
potentially unintended changes to our additions.

To apply these approaches, one may follow steps similar to the following
to generate a pair of patches that show the differences between upstream
Rust and the kernel (for the subset of `alloc` we use) before and after
applying this patch:

    # Get the difference with respect to the old version.
    git -C rust checkout $(linux/scripts/min-tool-version.sh rustc)
    git -C linux ls-tree -r --name-only HEAD -- rust/alloc |
        cut -d/ -f3- |
        grep -Fv README.md |
        xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH
    git -C linux diff --patch-with-stat --summary -R > old.patch
    git -C linux restore rust/alloc

    # Apply this patch.
    git -C linux am rust-upgrade.patch

    # Get the difference with respect to the new version.
    git -C rust checkout $(linux/scripts/min-tool-version.sh rustc)
    git -C linux ls-tree -r --name-only HEAD -- rust/alloc |
        cut -d/ -f3- |
        grep -Fv README.md |
        xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH
    git -C linux diff --patch-with-stat --summary -R > new.patch
    git -C linux restore rust/alloc

Now one may check the `new.patch` to take a look at the additions (first
approach) or at the difference between those two patches (second
approach). For the latter, a side-by-side tool is recommended.

Link: https://github.com/rust-lang/rust/blob/stable/RELEASES.md#version-1750-2023-12-28 [1]
Link: https://rust-for-linux.com/rust-version-policy [2]
Link: https://github.com/rust-lang/rust/issues/91850 [3]
Link: https://github.com/Rust-for-Linux/linux/issues/2 [4]
Link: https://github.com/rust-lang/rust/issues/96283 [5]
Reviewed-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Tested-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://lore.kernel.org/r/20231224172128.271447-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-01-22 15:18:05 +01:00
FUJITA Tomonori
f20fd5449a rust: core abstractions for network PHY drivers
This patch adds abstractions to implement network PHY drivers; the
driver registration and bindings for some of callback functions in
struct phy_driver and many genphy_ functions.

This feature is enabled with CONFIG_RUST_PHYLIB_ABSTRACTIONS=y.

This patch enables unstable const_maybe_uninit_zeroed feature for
kernel crate to enable unsafe code to handle a constant value with
uninitialized data. With the feature, the abstractions can initialize
a phy_driver structure with zero easily; instead of initializing all
the members by hand. It's supposed to be stable in the not so distant
future.

Link: https://github.com/rust-lang/rust/pull/116218

Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-12-15 09:35:50 +00:00
Alice Ryhl
7324b88975 rust: workqueue: add helper for defining work_struct fields
The main challenge with defining `work_struct` fields is making sure
that the function pointer stored in the `work_struct` is appropriate for
the work item type it is embedded in. It needs to know the offset of the
`work_struct` field being used (even if there are several!) so that it
can do a `container_of`, and it needs to know the type of the work item
so that it can call into the right user-provided code. All of this needs
to happen in a way that provides a safe API to the user, so that users
of the workqueue cannot mix up the function pointers.

There are three important pieces that are relevant when doing this:

 * The pointer type.
 * The work item struct. This is what the pointer points at.
 * The `work_struct` field. This is a field of the work item struct.

This patch introduces a separate trait for each piece. The pointer type
is given a `WorkItemPointer` trait, which pointer types need to
implement to be usable with the workqueue. This trait will be
implemented for `Arc` and `Box` in a later patch in this patchset.
Implementing this trait is unsafe because this is where the
`container_of` operation happens, but user-code will not need to
implement it themselves.

The work item struct should then implement the `WorkItem` trait. This
trait is where user-code specifies what they want to happen when a work
item is executed. It also specifies what the correct pointer type is.

Finally, to make the work item struct know the offset of its
`work_struct` field, we use a trait called `HasWork<T, ID>`. If a type
implements this trait, then the type declares that, at the given offset,
there is a field of type `Work<T, ID>`. The trait is marked unsafe
because the OFFSET constant must be correct, but we provide an
`impl_has_work!` macro that can safely implement `HasWork<T>` on a type.
The macro expands to something that only compiles if the specified field
really has the type `Work<T>`. It is used like this:

```
struct MyWorkItem {
    work_field: Work<MyWorkItem, 1>,
}

impl_has_work! {
    impl HasWork<MyWorkItem, 1> for MyWorkItem { self.work_field }
}
```

Note that since the `Work` type is annotated with an id, you can have
several `work_struct` fields by using a different id for each one.

Co-developed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Reviewed-by: Andreas Hindborg <a.hindborg@samsung.com>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2023-09-25 09:46:42 -10:00