kernel/linux.git/fs/btrfs/compression.c, branch v6.19.12

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

2025-12-06T01:01:20+00:00

Pull KVM updates from Paolo Bonzini: "ARM: - Support for userspace handling of synchronous external aborts (SEAs), allowing the VMM to potentially handle the abort in a non-fatal manner - Large rework of the VGIC's list register handling with the goal of supporting more active/pending IRQs than available list registers in hardware. In addition, the VGIC now supports EOImode==1 style deactivations for IRQs which may occur on a separate vCPU than the one that acked the IRQ - Support for FEAT_XNX (user / privileged execute permissions) and FEAT_HAF (hardware update to the Access Flag) in the software page table walkers and shadow MMU - Allow page table destruction to reschedule, fixing long need_resched latencies observed when destroying a large VM - Minor fixes to KVM and selftests Loongarch: - Get VM PMU capability from HW GCFG register - Add AVEC basic support - Use 64-bit register definition for EIOINTC - Add KVM timer test cases for tools/selftests RISC/V: - SBI message passing (MPXY) support for KVM guest - Give a new, more specific error subcode for the case when in-kernel AIA virtualization fails to allocate IMSIC VS-file - Support KVM_DIRTY_LOG_INITIALLY_SET, enabling dirty log gradually in small chunks - Fix guest page fault within HLV* instructions - Flush VS-stage TLB after VCPU migration for Andes cores s390: - Always allocate ESCA (Extended System Control Area), instead of starting with the basic SCA and converting to ESCA with the addition of the 65th vCPU. The price is increased number of exits (and worse performance) on z10 and earlier processor; ESCA was introduced by z114/z196 in 2010 - VIRT_XFER_TO_GUEST_WORK support - Operation exception forwarding support - Cleanups x86: - Skip the costly "zap all SPTEs" on an MMIO generation wrap if MMIO SPTE caching is disabled, as there can't be any relevant SPTEs to zap - Relocate a misplaced export - Fix an async #PF bug where KVM would clear the completion queue when the guest transitioned in and out of paging mode, e.g. when handling an SMI and then returning to paged mode via RSM - Leave KVM's user-return notifier registered even when disabling virtualization, as long as kvm.ko is loaded. On reboot/shutdown, keeping the notifier registered is ok; the kernel does not use the MSRs and the callback will run cleanly and restore host MSRs if the CPU manages to return to userspace before the system goes down - Use the checked version of {get,put}_user() - Fix a long-lurking bug where KVM's lack of catch-up logic for periodic APIC timers can result in a hard lockup in the host - Revert the periodic kvmclock sync logic now that KVM doesn't use a clocksource that's subject to NTP corrections - Clean up KVM's handling of MMIO Stale Data and L1TF, and bury the latter behind CONFIG_CPU_MITIGATIONS - Context switch XCR0, XSS, and PKRU outside of the entry/exit fast path; the only reason they were handled in the fast path was to paper of a bug in the core #MC code, and that has long since been fixed - Add emulator support for AVX MOV instructions, to play nice with emulated devices whose guest drivers like to access PCI BARs with large multi-byte instructions x86 (AMD): - Fix a few missing "VMCB dirty" bugs - Fix the worst of KVM's lack of EFER.LMSLE emulation - Add AVIC support for addressing 4k vCPUs in x2AVIC mode - Fix incorrect handling of selective CR0 writes when checking intercepts during emulation of L2 instructions - Fix a currently-benign bug where KVM would clobber SPEC_CTRL[63:32] on VMRUN and #VMEXIT - Fix a bug where KVM corrupt the guest code stream when re-injecting a soft interrupt if the guest patched the underlying code after the VM-Exit, e.g. when Linux patches code with a temporary INT3 - Add KVM_X86_SNP_POLICY_BITS to advertise supported SNP policy bits to userspace, and extend KVM "support" to all policy bits that don't require any actual support from KVM x86 (Intel): - Use the root role from kvm_mmu_page to construct EPTPs instead of the current vCPU state, partly as worthwhile cleanup, but mostly to pave the way for tracking per-root TLB flushes, and elide EPT flushes on pCPU migration if the root is clean from a previous flush - Add a few missing nested consistency checks - Rip out support for doing "early" consistency checks via hardware as the functionality hasn't been used in years and is no longer useful in general; replace it with an off-by-default module param to WARN if hardware fails a check that KVM does not perform - Fix a currently-benign bug where KVM would drop the guest's SPEC_CTRL[63:32] on VM-Enter - Misc cleanups - Overhaul the TDX code to address systemic races where KVM (acting on behalf of userspace) could inadvertantly trigger lock contention in the TDX-Module; KVM was either working around these in weird, ugly ways, or was simply oblivious to them (though even Yan's devilish selftests could only break individual VMs, not the host kernel) - Fix a bug where KVM could corrupt a vCPU's cpu_list when freeing a TDX vCPU, if creating said vCPU failed partway through - Fix a few sparse warnings (bad annotation, 0 != NULL) - Use struct_size() to simplify copying TDX capabilities to userspace - Fix a bug where TDX would effectively corrupt user-return MSR values if the TDX Module rejects VP.ENTER and thus doesn't clobber host MSRs as expected Selftests: - Fix a math goof in mmu_stress_test when running on a single-CPU system/VM - Forcefully override ARCH from x86_64 to x86 to play nice with specifying ARCH=x86_64 on the command line - Extend a bunch of nested VMX to validate nested SVM as well - Add support for LA57 in the core VM_MODE_xxx macro, and add a test to verify KVM can save/restore nested VMX state when L1 is using 5-level paging, but L2 is not - Clean up the guest paging code in anticipation of sharing the core logic for nested EPT and nested NPT guest_memfd: - Add NUMA mempolicy support for guest_memfd, and clean up a variety of rough edges in guest_memfd along the way - Define a CLASS to automatically handle get+put when grabbing a guest_memfd from a memslot to make it harder to leak references - Enhance KVM selftests to make it easer to develop and debug selftests like those added for guest_memfd NUMA support, e.g. where test and/or KVM bugs often result in hard-to-debug SIGBUS errors - Misc cleanups Generic: - Use the recently-added WQ_PERCPU when creating the per-CPU workqueue for irqfd cleanup - Fix a goof in the dirty ring documentation - Fix choice of target for directed yield across different calls to kvm_vcpu_on_spin(); the function was always starting from the first vCPU instead of continuing the round-robin search" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (260 commits) KVM: arm64: at: Update AF on software walk only if VM has FEAT_HAFDBS KVM: arm64: at: Use correct HA bit in TCR_EL2 when regime is EL2 KVM: arm64: Document KVM_PGTABLE_PROT_{UX,PX} KVM: arm64: Fix spelling mistake "Unexpeced" -> "Unexpected" KVM: arm64: Add break to default case in kvm_pgtable_stage2_pte_prot() KVM: arm64: Add endian casting to kvm_swap_s[12]_desc() KVM: arm64: Fix compilation when CONFIG_ARM64_USE_LSE_ATOMICS=n KVM: arm64: selftests: Add test for AT emulation KVM: arm64: nv: Expose hardware access flag management to NV guests KVM: arm64: nv: Implement HW access flag management in stage-2 SW PTW KVM: arm64: Implement HW access flag management in stage-1 SW PTW KVM: arm64: Propagate PTW errors up to AT emulation KVM: arm64: Add helper for swapping guest descriptor KVM: arm64: nv: Use pgtable definitions in stage-2 walk KVM: arm64: Handle endianness in read helper for emulated PTW KVM: arm64: nv: Stop passing vCPU through void ptr in S2 PTW KVM: arm64: Call helper for reading descriptors directly KVM: arm64: nv: Advertise support for FEAT_XNX KVM: arm64: Teach ptdump about FEAT_XNX permissions KVM: s390: Use generic VIRT_XFER_TO_GUEST_WORK functions ...

btrfs: fix incomplete parameter rename in btrfs_decompress()

2025-11-24T21:42:24+00:00

Commit 2c25716dcc25 ("btrfs: zlib: fix and simplify the inline extent decompression") renamed the 'start_byte' parameter to 'dest_pgoff' in the btrfs_decompress(). The remaining 'start_byte' references are inconsistent with the actual implementation and may cause confusion for developers. Ensure consistency between function declaration and implementation. Signed-off-by: Zhen Ni Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: enable encoded read/write/send for bs > ps cases

2025-11-24T21:42:24+00:00

Since the read verification and read repair are all supporting bs > ps without large folios now, we can enable encoded read/write/send. Now we can relax the alignment in assert_bbio_alignment() to min(blocksize, PAGE_SIZE). But also add the extra blocksize based alignment check for the logical and length of the bbio. There is a pitfall in btrfs_add_compress_bio_folios(), which relies on the folios passed in to meet the minimal folio order. But now we can pass regular page sized folios in, update it to check each folio's size instead of using the minimal folio size. This allows btrfs_add_compress_bio_folios() to even handle folios array with different sizes, thankfully we don't yet need to handle such crazy situation. Signed-off-by: Qu Wenruo Signed-off-by: David Sterba

btrfs: simplify list initialization in btrfs_compr_pool_scan()

2025-11-24T21:42:22+00:00

In btrfs_compr_pool_scan(), use LIST_HEAD() to declare and initialize the 'remove' list_head in one step instead of using INIT_LIST_HEAD() separately. Signed-off-by: Baolin Liu Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: remove btrfs_fs_info::compressed_write_workers

2025-11-24T21:42:19+00:00

The reason why end_bbio_compressed_write() queues a work into compressed_write_workers wq is for end_compressed_writeback() call, as it will grab all the involved folios and clear the writeback flags, which may sleep. However now we always run btrfs_bio::end_io() in task context, there is no need to queue the work anymore. Just remove btrfs_fs_info::compressed_write_workers and compressed_bio::write_end_work. There is a comment about the works queued into compressed_write_workers, now change to flush endio wq instead, which is responsible to handle all data endio functions. Signed-off-by: Qu Wenruo Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: remove btrfs_bio::fs_info by extracting it from btrfs_bio::inode

2025-11-24T21:40:16+00:00

Currently there is only one caller which doesn't populate btrfs_bio::inode, and that's scrub. The idea is scrub doesn't want any automatic csum verification nor read-repair, as everything will be handled by scrub itself. However that behavior is really no different than metadata inode, thus we can reuse btree_inode as btrfs_bio::inode for scrub. The only exception is in btrfs_submit_chunk() where if a bbio is from scrub or data reloc inode, we set rst_search_commit_root to true. This means we still need a way to distinguish scrub from metadata, but that can be done by a new flag inside btrfs_bio. Now btrfs_bio::inode is a mandatory parameter, we can extract fs_info from that inode thus can remove btrfs_bio::fs_info to save 8 bytes from btrfs_bio structure. Signed-off-by: Qu Wenruo Reviewed-by: David Sterba Signed-off-by: David Sterba

mm/filemap: Add NUMA mempolicy support to filemap_alloc_folio()

2025-10-20T13:30:25+00:00

Add a mempolicy parameter to filemap_alloc_folio() to enable NUMA-aware page cache allocations. This will be used by upcoming changes to support NUMA policies in guest-memfd, where guest_memory need to be allocated NUMA policy specified by VMM. All existing users pass NULL maintaining current behavior. Reviewed-by: Pankaj Gupta Reviewed-by: Vlastimil Babka Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: David Hildenbrand Signed-off-by: Shivank Garg Tested-by: Ashish Kalra Link: https://lore.kernel.org/r/20250827175247.83322-4-shivankg@amd.com Signed-off-by: Sean Christopherson

btrfs: prepare compression folio alloc/free for bs > ps cases

2025-09-23T06:49:24+00:00

This includes the following preparation for bs > ps cases: - Always alloc/free the folio directly if bs > ps This adds a new @fs_info parameter for btrfs_alloc_compr_folio(), thus affecting all compression algorithms. For btrfs_free_compr_folio() it needs no parameter for now, as we can use the folio size to skip the caching part. For now the change is just to passing a @fs_info into the function, all the folio size assumption is still based on page size. - Properly zero the last folio in compress_file_range() Since the compressed folios can be larger than a page, we need to properly zero the whole folio. - Use correct folio size for btrfs_add_compressed_bio_folios() Instead of page size, use the correct folio size. - Use correct folio size/shift for btrfs_compress_filemap_get_folio() As we are not only using simple page sized folios anymore. - Use correct folio size for btrfs_decompress() There is an ASSERT() making sure the decompressed range is no larger than a page, which will be triggered for bs > ps cases. - Skip readahead for compressed pages Similar to subpage cases. - Make btrfs_alloc_folio_array() to accept a new @order parameter - Add a helper to calculate the minimal folio size All those changes should not affect the existing bs <= ps handling. Signed-off-by: Qu Wenruo Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: fix typos in comments and strings

2025-09-23T06:49:16+00:00

Annual typo fixing pass. Strangely codespell found only about 30% of what is in this patch, the rest was done manually using text spellchecker with a custom dictionary of acceptable terms. Reviewed-by: Neal Gompa Signed-off-by: David Sterba

btrfs: rename btrfs_compress_op to btrfs_compress_levels

2025-09-23T06:49:16+00:00

Since all workspace managers are per-fs, there is no need nor no way to store them inside btrfs_compress_op::wsm anymore. With that said, we can do the following modifications: - Remove zstd_workspace_mananger::ops Zstd always grab the global btrfs_compress_op[]. - Remove btrfs_compress_op::wsm member - Rename btrfs_compress_op to btrfs_compress_levels This should make it more clear that btrfs_compress_levels structures are only to indicate the levels of each compress algorithm. Signed-off-by: Qu Wenruo Reviewed-by: David Sterba Signed-off-by: David Sterba