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2020-06-09mmap locking API: convert mmap_sem commentsMichel Lespinasse1-3/+2
Convert comments that reference mmap_sem to reference mmap_lock instead. [[email protected]: fix up linux-next leftovers] [[email protected]: s/lockaphore/lock/, per Vlastimil] [[email protected]: more linux-next fixups, per Michel] Signed-off-by: Michel Lespinasse <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Reviewed-by: Vlastimil Babka <[email protected]> Reviewed-by: Daniel Jordan <[email protected]> Cc: Davidlohr Bueso <[email protected]> Cc: David Rientjes <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Jason Gunthorpe <[email protected]> Cc: Jerome Glisse <[email protected]> Cc: John Hubbard <[email protected]> Cc: Laurent Dufour <[email protected]> Cc: Liam Howlett <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Ying Han <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Linus Torvalds <[email protected]>
2020-06-09mmap locking API: use coccinelle to convert mmap_sem rwsem call sitesMichel Lespinasse1-2/+2
This change converts the existing mmap_sem rwsem calls to use the new mmap locking API instead. The change is generated using coccinelle with the following rule: // spatch --sp-file mmap_lock_api.cocci --in-place --include-headers --dir . @@ expression mm; @@ ( -init_rwsem +mmap_init_lock | -down_write +mmap_write_lock | -down_write_killable +mmap_write_lock_killable | -down_write_trylock +mmap_write_trylock | -up_write +mmap_write_unlock | -downgrade_write +mmap_write_downgrade | -down_read +mmap_read_lock | -down_read_killable +mmap_read_lock_killable | -down_read_trylock +mmap_read_trylock | -up_read +mmap_read_unlock ) -(&mm->mmap_sem) +(mm) Signed-off-by: Michel Lespinasse <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Reviewed-by: Daniel Jordan <[email protected]> Reviewed-by: Laurent Dufour <[email protected]> Reviewed-by: Vlastimil Babka <[email protected]> Cc: Davidlohr Bueso <[email protected]> Cc: David Rientjes <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Jason Gunthorpe <[email protected]> Cc: Jerome Glisse <[email protected]> Cc: John Hubbard <[email protected]> Cc: Liam Howlett <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Ying Han <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Linus Torvalds <[email protected]>
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152Thomas Gleixner1-5/+1
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner <[email protected]> Reviewed-by: Allison Randal <[email protected]> Cc: [email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]>
2018-07-16powerpc/64s: Remove POWER9 DD1 supportNicholas Piggin1-4/+0
POWER9 DD1 was never a product. It is no longer supported by upstream firmware, and it is not effectively supported in Linux due to lack of testing. Signed-off-by: Nicholas Piggin <[email protected]> Reviewed-by: Michael Ellerman <[email protected]> [mpe: Remove arch_make_huge_pte() entirely] Signed-off-by: Michael Ellerman <[email protected]>
2018-04-04cxl: Fix possible deadlock when processing page faults from cxllibFrederic Barrat1-30/+55
cxllib_handle_fault() is called by an external driver when it needs to have the host resolve page faults for a buffer. The buffer can cover several pages and VMAs. The function iterates over all the pages used by the buffer, based on the page size of the VMA. To ensure some stability while processing the faults, the thread T1 grabs the mm->mmap_sem semaphore with read access (R1). However, when processing a page fault for a single page, one of the underlying functions, copro_handle_mm_fault(), also grabs the same semaphore with read access (R2). So the thread T1 takes the semaphore twice. If another thread T2 tries to access the semaphore in write mode W1 (say, because it wants to allocate memory and calls 'brk'), then that thread T2 will have to wait because there's a reader (R1). If the thread T1 is processing a new page at that time, it won't get an automatic grant at R2, because there's now a writer thread waiting (T2). And we have a deadlock. The timeline is: 1. thread T1 owns the semaphore with read access R1 2. thread T2 requests write access W1 and waits 3. thread T1 requests read access R2 and waits The fix is for the thread T1 to release the semaphore R1 once it got the information it needs from the current VMA. The address space/VMAs could evolve while T1 iterates over the full buffer, but in the unlikely case where T1 misses a page, the external driver will raise a new page fault when retrying the memory access. Fixes: 3ced8d730063 ("cxl: Export library to support IBM XSL") Cc: [email protected] # 4.13+ Signed-off-by: Frederic Barrat <[email protected]> Signed-off-by: Michael Ellerman <[email protected]>
2018-03-13cxl: read PHB indications from the device treePhilippe Bergheaud1-1/+1
Configure the P9 XSL_DSNCTL register with PHB indications found in the device tree, or else use legacy hard-coded values. Signed-off-by: Philippe Bergheaud <[email protected]> Reviewed-by: Frederic Barrat <[email protected]> Reviewed-by: Christophe Lombard <[email protected]> Signed-off-by: Michael Ellerman <[email protected]>
2018-01-19cxl: Add support for ASB_Notify on POWER9Christophe Lombard1-1/+2
The POWER9 core supports a new feature: ASB_Notify which requires the support of the Special Purpose Register: TIDR. The ASB_Notify command, generated by the AFU, will attempt to wake-up the host thread identified by the particular LPID:PID:TID. This patch assign a unique TIDR (thread id) for the current thread which will be used in the process element entry. Signed-off-by: Christophe Lombard <[email protected]> Reviewed-by: Philippe Bergheaud <[email protected]> Acked-by: Frederic Barrat <[email protected]> Reviewed-by: Vaibhav Jain <[email protected]> Acked-by: Andrew Donnellan <[email protected]> Signed-off-by: Michael Ellerman <[email protected]>
2017-09-29cxl: Fix memory page not handledChristophe Lombard1-2/+11
The in-kernel 'library' API can be called by drivers to help interaction with an IBM XSL on a POWER9 system. The cxllib_handle_fault() API is used to handle memory fault. All memory pages of the specified buffer have to be handled but under certain conditions,the last page may not be touched, and the address the adapter is trying to access is never sent to the kernel for resolution. This patch reworks start address of the loop with an address aligned on the page size. In this context, the last page is not missed. Signed-off-by: Christophe Lombard <[email protected]> Acked-by: Frederic Barrat <[email protected]> Acked-by: Andrew Donnellan <[email protected]> Fixes: 3ced8d730063 ("cxl: Export library to support IBM XSL"); Signed-off-by: Michael Ellerman <[email protected]>
2017-07-03cxl: Export library to support IBM XSLChristophe Lombard1-0/+246
This patch exports a in-kernel 'library' API which can be called by other drivers to help interacting with an IBM XSL on a POWER9 system. The XSL (Translation Service Layer) is a stripped down version of the PSL (Power Service Layer) used in some cards such as the Mellanox CX5. Like the PSL, it implements the CAIA architecture, but has a number of differences, mostly in it's implementation dependent registers. The XSL also uses a special DMA cxl mode, which uses a slightly different init sequence for the CAPP and PHB. Signed-off-by: Andrew Donnellan <[email protected]> Signed-off-by: Christophe Lombard <[email protected]> Acked-by: Frederic Barrat <[email protected]> Signed-off-by: Michael Ellerman <[email protected]>