kernel/linux.git/arch/nios2/mm/cacheflush.c, branch v7.1

mm: introduce memdesc_flags_t

2025-09-13T23:55:07+00:00

Patch series "Add and use memdesc_flags_t". At some point struct page will be separated from struct slab and struct folio. This is a step towards that by introducing a type for the 'flags' word of all three structures. This gives us a certain amount of type safety by establishing that some of these unsigned longs are different from other unsigned longs in that they contain things like node ID, section number and zone number in the upper bits. That lets us have functions that can be easily called by anyone who has a slab, folio or page (but not easily by anyone else) to get the node or zone. There's going to be some unusual merge problems with this as some odd bits of the kernel decide they want to print out the flags value or something similar by writing page->flags and now they'll need to write page->flags.f instead. That's most of the churn here. Maybe we should be removing these things from the debug output? This patch (of 11): Wrap the unsigned long flags in a typedef. In upcoming patches, this will provide a strong hint that you can't just pass a random unsigned long to functions which take this as an argument. [willy@infradead.org: s/flags/flags.f/ in several architectures] Link: https://lkml.kernel.org/r/aKMgPRLD-WnkPxYm@casper.infradead.org [nicola.vetrini@gmail.com: mips: fix compilation error] Link: https://lore.kernel.org/lkml/CA+G9fYvkpmqGr6wjBNHY=dRp71PLCoi2341JxOudi60yqaeUdg@mail.gmail.com/ Link: https://lkml.kernel.org/r/20250825214245.1838158-1-nicola.vetrini@gmail.com Link: https://lkml.kernel.org/r/20250805172307.1302730-1-willy@infradead.org Link: https://lkml.kernel.org/r/20250805172307.1302730-2-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) Signed-off-by: Matthew Wilcox (Oracle) Acked-by: Zi Yan Cc: Shakeel Butt Signed-off-by: Andrew Morton

nios2: fix flush_dcache_page() for usage from irq context

2023-08-24T23:20:31+00:00

Since at least kernel 6.1, flush_dcache_page() is called with IRQs disabled, e.g. from aio_complete(). But the current implementation for flush_dcache_page() on NIOS2 unintentionally re-enables IRQs, which may lead to deadlocks. Fix it by using xa_lock_irqsave() and xa_unlock_irqrestore() for the flush_dcache_mmap_*lock() macros instead. Link: https://lkml.kernel.org/r/ZOTF5WWURQNH9+iw@p100 Signed-off-by: Helge Deller Cc: Dinh Nguyen Signed-off-by: Andrew Morton

nios2: implement the new page table range API

2023-08-24T23:20:22+00:00

Add set_ptes(), update_mmu_cache_range(), flush_icache_pages() and flush_dcache_folio(). Change the PG_arch_1 (aka PG_dcache_dirty) flag from being per-page to per-folio. Link: https://lkml.kernel.org/r/20230802151406.3735276-19-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) Acked-by: Mike Rapoport (IBM) Cc: Dinh Nguyen Signed-off-by: Andrew Morton

mm: move page_mapping_file to pagemap.h

2021-04-30T18:20:37+00:00

page_mapping_file() is only used by some architectures, and then it is usually only used in one place. Make it a static inline function so other architectures don't have to carry this dead code. Link: https://lkml.kernel.org/r/20210317123011.350118-1-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: David Hildenbrand Acked-by: Mike Rapoport Cc: Huang Ying Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

nios2: update_mmu_cache preload the TLB with the new PTE

2019-03-06T21:29:35+00:00

Rather than flush the TLB entry when installing a new PTE to allow the fast TLB reload to re-fill the TLB, just refill the TLB entry when removing the old one. Signed-off-by: Nicholas Piggin Signed-off-by: Ley Foon Tan

nios2: update_mmu_cache clear the old entry from the TLB

2019-03-06T21:29:35+00:00

Fault paths like do_read_fault will install a Linux pte with the young bit clear. The CPU will fault again because the TLB has not been updated, this time a valid pte exists so handle_pte_fault will just set the young bit with ptep_set_access_flags, which flushes the TLB. The TLB is flushed so the next attempt will go to the fast TLB handler which loads the TLB with the new Linux pte. The access then proceeds. This design is fragile to depend on the young bit being clear after the initial Linux fault. A proposed core mm change to immediately set the young bit upon such a fault, results in ptep_set_access_flags not flushing the TLB because it finds no change to the pte. The spurious fault fix path only flushes the TLB if the access was a store. If it was a load, then this results in an infinite loop of page faults. This change adds a TLB flush in update_mmu_cache, which removes that TLB entry upon the first fault. This will cause the fast TLB handler to load the new pte and avoid the Linux page fault entirely. Signed-off-by: Nicholas Piggin Signed-off-by: Ley Foon Tan

mm: fix races between swapoff and flush dcache

2018-04-06T04:36:26+00:00

Thanks to commit 4b3ef9daa4fc ("mm/swap: split swap cache into 64MB trunks"), after swapoff the address_space associated with the swap device will be freed. So page_mapping() users which may touch the address_space need some kind of mechanism to prevent the address_space from being freed during accessing. The dcache flushing functions (flush_dcache_page(), etc) in architecture specific code may access the address_space of swap device for anonymous pages in swap cache via page_mapping() function. But in some cases there are no mechanisms to prevent the swap device from being swapoff, for example, CPU1 CPU2 __get_user_pages() swapoff() flush_dcache_page() mapping = page_mapping() ... exit_swap_address_space() ... kvfree(spaces) mapping_mapped(mapping) The address space may be accessed after being freed. But from cachetlb.txt and Russell King, flush_dcache_page() only care about file cache pages, for anonymous pages, flush_anon_page() should be used. The implementation of flush_dcache_page() in all architectures follows this too. They will check whether page_mapping() is NULL and whether mapping_mapped() is true to determine whether to flush the dcache immediately. And they will use interval tree (mapping->i_mmap) to find all user space mappings. While mapping_mapped() and mapping->i_mmap isn't used by anonymous pages in swap cache at all. So, to fix the race between swapoff and flush dcache, __page_mapping() is add to return the address_space for file cache pages and NULL otherwise. All page_mapping() invoking in flush dcache functions are replaced with page_mapping_file(). [akpm@linux-foundation.org: simplify page_mapping_file(), per Mike] Link: http://lkml.kernel.org/r/20180305083634.15174-1-ying.huang@intel.com Signed-off-by: "Huang, Ying" Reviewed-by: Andrew Morton Cc: Minchan Kim Cc: Michal Hocko Cc: Johannes Weiner Cc: Mel Gorman Cc: Dave Hansen Cc: Chen Liqin Cc: Russell King Cc: Yoshinori Sato Cc: "James E.J. Bottomley" Cc: Guan Xuetao Cc: "David S. Miller" Cc: Chris Zankel Cc: Vineet Gupta Cc: Ley Foon Tan Cc: Ralf Baechle Cc: Andi Kleen Cc: Mike Rapoport Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

nios2: fix cache coherency

2015-11-26T14:25:58+00:00

There is intermittent cache coherency issue caught in toolchian tests. Revert to use flushd. Signed-off-by: Ley Foon Tan

nios2: rework cache

2015-04-24T06:49:53+00:00

- flush dcache before flush instruction cache - remork update_mmu_cache and flush_dcache_page - add shmparam.h Signed-off-by: Ley Foon Tan

nios2: remove end address checking for initda

2015-04-20T02:52:06+00:00

Remove the end address checking for initda function. We need to invalidate each address line for initda instruction, from start to end address. Signed-off-by: Ley Foon Tan