kernel/linux
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ synced 2026-11-10 20:48:12 +00:00
Code Issues Releases Packages Activity
linux/io_uring/memmap.h

39 lines
1.1 KiB
Raw Permalink Normal View History

io_uring: move mapping/allocation helpers to a separate file Move the related code from io_uring.c into memmap.c. No functional changes in this patch, just cleaning it up a bit now that the full transition is done. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-03-27 14:59:09 -06:00
io_uring/memmap: implement mmap for regions The patch implements mmap for the param region and enables the kernel allocation mode. Internally it uses a fixed mmap offset, however the user has to use the offset returned in struct io_uring_region_desc::mmap_offset. Note, mmap doesn't and can't take ->uring_lock and the region / ring lookup is protected by ->mmap_lock, and it's directly peeking at ctx->param_region. We can't protect io_create_region() with the mmap_lock as it'd deadlock, which is why io_create_region_mmap_safe() initialises it for us in a temporary variable and then publishes it with the lock taken. It's intentionally decoupled from main region helpers, and in the future we might want to have a list of active regions, which then could be protected by the ->mmap_lock. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/0f1212bd6af7fb39b63514b34fae8948014221d1.1732886067.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-29 13:34:32 +00:00
io_uring/zcrx: add interface queue and refill queue Add a new object called an interface queue (ifq) that represents a net rx queue that has been configured for zero copy. Each ifq is registered using a new registration opcode IORING_REGISTER_ZCRX_IFQ. The refill queue is allocated by the kernel and mapped by userspace using a new offset IORING_OFF_RQ_RING, in a similar fashion to the main SQ/CQ. It is used by userspace to return buffers that it is done with, which will then be re-used by the netdev again. The main CQ ring is used to notify userspace of received data by using the upper 16 bytes of a big CQE as a new struct io_uring_zcrx_cqe. Each entry contains the offset + len to the data. For now, each io_uring instance only has a single ifq. Reviewed-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: David Wei <dw@davidwei.uk> Acked-by: Jakub Kicinski <kuba@kernel.org> Link: https://lore.kernel.org/r/20250215000947.789731-2-dw@davidwei.uk Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-02-14 16:09:36 -08:00
io_uring/memmap: implement mmap for regions The patch implements mmap for the param region and enables the kernel allocation mode. Internally it uses a fixed mmap offset, however the user has to use the offset returned in struct io_uring_region_desc::mmap_offset. Note, mmap doesn't and can't take ->uring_lock and the region / ring lookup is protected by ->mmap_lock, and it's directly peeking at ctx->param_region. We can't protect io_create_region() with the mmap_lock as it'd deadlock, which is why io_create_region_mmap_safe() initialises it for us in a temporary variable and then publishes it with the lock taken. It's intentionally decoupled from main region helpers, and in the future we might want to have a list of active regions, which then could be protected by the ->mmap_lock. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/0f1212bd6af7fb39b63514b34fae8948014221d1.1732886067.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-29 13:34:32 +00:00
io_uring/zcrx: let zcrx choose region for mmaping In preparation for adding multiple ifqs, add a helper returning a region for mmaping zcrx refill queue. For now it's trivial and returns the same ctx global ->zcrx_region. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/d9006e2ef8cd5e5b337c2ba2228ede8409eb60f2.1745141261.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-04-20 10:31:18 +01:00
io_uring: update parameter name in io_pin_pages function declaration Rename first parameter in io_pin_pages from ubuf to uaddr for consistency between declaration and implementation. Signed-off-by: Long Li <leo.lilong@huawei.com> Link: https://lore.kernel.org/r/20250509063015.3799255-1-leo.lilong@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-05-09 14:30:15 +08:00
io_uring: move mapping/allocation helpers to a separate file Move the related code from io_uring.c into memmap.c. No functional changes in this patch, just cleaning it up a bit now that the full transition is done. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-03-27 14:59:09 -06:00
io_uring: introduce concept of memory regions We've got a good number of mappings we share with the userspace, that includes the main rings, provided buffer rings, upcoming rings for zerocopy rx and more. All of them duplicate user argument parsing and some internal details as well (page pinnning, huge page optimisations, mmap'ing, etc.) Introduce a notion of regions. For userspace for now it's just a new structure called struct io_uring_region_desc which is supposed to parameterise all such mapping / queue creations. A region either represents a user provided chunk of memory, in which case the user_addr field should point to it, or a request for the kernel to allocate the memory, in which case the user would need to mmap it after using the offset returned in the mmap_offset field. With a uniform userspace API we can avoid additional boiler plate code and apply future optimisation to all of them at once. Internally, there is a new structure struct io_mapped_region holding all relevant runtime information and some helpers to work with it. This patch limits it to user provided regions. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/0e6fe25818dfbaebd1bd90b870a6cac503fe1a24.1731689588.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-15 16:54:41 +00:00
io_uring/memmap: implement mmap for regions The patch implements mmap for the param region and enables the kernel allocation mode. Internally it uses a fixed mmap offset, however the user has to use the offset returned in struct io_uring_region_desc::mmap_offset. Note, mmap doesn't and can't take ->uring_lock and the region / ring lookup is protected by ->mmap_lock, and it's directly peeking at ctx->param_region. We can't protect io_create_region() with the mmap_lock as it'd deadlock, which is why io_create_region_mmap_safe() initialises it for us in a temporary variable and then publishes it with the lock taken. It's intentionally decoupled from main region helpers, and in the future we might want to have a list of active regions, which then could be protected by the ->mmap_lock. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/0f1212bd6af7fb39b63514b34fae8948014221d1.1732886067.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-29 13:34:32 +00:00
io_uring: introduce concept of memory regions We've got a good number of mappings we share with the userspace, that includes the main rings, provided buffer rings, upcoming rings for zerocopy rx and more. All of them duplicate user argument parsing and some internal details as well (page pinnning, huge page optimisations, mmap'ing, etc.) Introduce a notion of regions. For userspace for now it's just a new structure called struct io_uring_region_desc which is supposed to parameterise all such mapping / queue creations. A region either represents a user provided chunk of memory, in which case the user_addr field should point to it, or a request for the kernel to allocate the memory, in which case the user would need to mmap it after using the offset returned in the mmap_offset field. With a uniform userspace API we can avoid additional boiler plate code and apply future optimisation to all of them at once. Internally, there is a new structure struct io_mapped_region holding all relevant runtime information and some helpers to work with it. This patch limits it to user provided regions. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/0e6fe25818dfbaebd1bd90b870a6cac503fe1a24.1731689588.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-15 16:54:41 +00:00
io_uring/memmap: flag vmap'ed regions Add internal flags for struct io_mapped_region. The first flag we need is IO_REGION_F_VMAPPED, that indicates that the pointer has to be unmapped on region destruction. For now all regions are vmap'ed, so it's set unconditionally. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/5a3d8046a038da97c0f8a8c8f1733fa3fc689d31.1732886067.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-29 13:34:24 +00:00
io_uring: introduce concept of memory regions We've got a good number of mappings we share with the userspace, that includes the main rings, provided buffer rings, upcoming rings for zerocopy rx and more. All of them duplicate user argument parsing and some internal details as well (page pinnning, huge page optimisations, mmap'ing, etc.) Introduce a notion of regions. For userspace for now it's just a new structure called struct io_uring_region_desc which is supposed to parameterise all such mapping / queue creations. A region either represents a user provided chunk of memory, in which case the user_addr field should point to it, or a request for the kernel to allocate the memory, in which case the user would need to mmap it after using the offset returned in the mmap_offset field. With a uniform userspace API we can avoid additional boiler plate code and apply future optimisation to all of them at once. Internally, there is a new structure struct io_mapped_region holding all relevant runtime information and some helpers to work with it. This patch limits it to user provided regions. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/0e6fe25818dfbaebd1bd90b870a6cac503fe1a24.1731689588.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-15 16:54:41 +00:00
io_uring: move mapping/allocation helpers to a separate file Move the related code from io_uring.c into memmap.c. No functional changes in this patch, just cleaning it up a bit now that the full transition is done. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-03-27 14:59:09 -06:00