diff options
Diffstat (limited to 'include/sysemu/dma.h')
| -rw-r--r-- | include/sysemu/dma.h | 117 |
1 files changed, 99 insertions, 18 deletions
diff --git a/include/sysemu/dma.h b/include/sysemu/dma.h index 80c5bc3e02..a052f7bca3 100644 --- a/include/sysemu/dma.h +++ b/include/sysemu/dma.h @@ -1,7 +1,7 @@ /* * DMA helper functions * - * Copyright (c) 2009 Red Hat + * Copyright (c) 2009, 2020 Red Hat * * This work is licensed under the terms of the GNU General Public License * (GNU GPL), version 2 or later. @@ -80,51 +80,118 @@ static inline bool dma_memory_valid(AddressSpace *as, MEMTXATTRS_UNSPECIFIED); } -static inline int dma_memory_rw_relaxed(AddressSpace *as, dma_addr_t addr, - void *buf, dma_addr_t len, - DMADirection dir) +static inline MemTxResult dma_memory_rw_relaxed(AddressSpace *as, + dma_addr_t addr, + void *buf, dma_addr_t len, + DMADirection dir) { - return (bool)address_space_rw(as, addr, MEMTXATTRS_UNSPECIFIED, - buf, len, dir == DMA_DIRECTION_FROM_DEVICE); + return address_space_rw(as, addr, MEMTXATTRS_UNSPECIFIED, + buf, len, dir == DMA_DIRECTION_FROM_DEVICE); } -static inline int dma_memory_read_relaxed(AddressSpace *as, dma_addr_t addr, - void *buf, dma_addr_t len) +static inline MemTxResult dma_memory_read_relaxed(AddressSpace *as, + dma_addr_t addr, + void *buf, dma_addr_t len) { return dma_memory_rw_relaxed(as, addr, buf, len, DMA_DIRECTION_TO_DEVICE); } -static inline int dma_memory_write_relaxed(AddressSpace *as, dma_addr_t addr, - const void *buf, dma_addr_t len) +static inline MemTxResult dma_memory_write_relaxed(AddressSpace *as, + dma_addr_t addr, + const void *buf, + dma_addr_t len) { return dma_memory_rw_relaxed(as, addr, (void *)buf, len, DMA_DIRECTION_FROM_DEVICE); } -static inline int dma_memory_rw(AddressSpace *as, dma_addr_t addr, - void *buf, dma_addr_t len, - DMADirection dir) +/** + * dma_memory_rw: Read from or write to an address space from DMA controller. + * + * Return a MemTxResult indicating whether the operation succeeded + * or failed (eg unassigned memory, device rejected the transaction, + * IOMMU fault). + * + * @as: #AddressSpace to be accessed + * @addr: address within that address space + * @buf: buffer with the data transferred + * @len: the number of bytes to read or write + * @dir: indicates the transfer direction + */ +static inline MemTxResult dma_memory_rw(AddressSpace *as, dma_addr_t addr, + void *buf, dma_addr_t len, + DMADirection dir) { dma_barrier(as, dir); return dma_memory_rw_relaxed(as, addr, buf, len, dir); } -static inline int dma_memory_read(AddressSpace *as, dma_addr_t addr, - void *buf, dma_addr_t len) +/** + * dma_memory_read: Read from an address space from DMA controller. + * + * Return a MemTxResult indicating whether the operation succeeded + * or failed (eg unassigned memory, device rejected the transaction, + * IOMMU fault). Called within RCU critical section. + * + * @as: #AddressSpace to be accessed + * @addr: address within that address space + * @buf: buffer with the data transferred + * @len: length of the data transferred + */ +static inline MemTxResult dma_memory_read(AddressSpace *as, dma_addr_t addr, + void *buf, dma_addr_t len) { return dma_memory_rw(as, addr, buf, len, DMA_DIRECTION_TO_DEVICE); } -static inline int dma_memory_write(AddressSpace *as, dma_addr_t addr, - const void *buf, dma_addr_t len) +/** + * address_space_write: Write to address space from DMA controller. + * + * Return a MemTxResult indicating whether the operation succeeded + * or failed (eg unassigned memory, device rejected the transaction, + * IOMMU fault). + * + * @as: #AddressSpace to be accessed + * @addr: address within that address space + * @buf: buffer with the data transferred + * @len: the number of bytes to write + */ +static inline MemTxResult dma_memory_write(AddressSpace *as, dma_addr_t addr, + const void *buf, dma_addr_t len) { return dma_memory_rw(as, addr, (void *)buf, len, DMA_DIRECTION_FROM_DEVICE); } -int dma_memory_set(AddressSpace *as, dma_addr_t addr, uint8_t c, dma_addr_t len); +/** + * dma_memory_set: Fill memory with a constant byte from DMA controller. + * + * Return a MemTxResult indicating whether the operation succeeded + * or failed (eg unassigned memory, device rejected the transaction, + * IOMMU fault). + * + * @as: #AddressSpace to be accessed + * @addr: address within that address space + * @c: constant byte to fill the memory + * @len: the number of bytes to fill with the constant byte + */ +MemTxResult dma_memory_set(AddressSpace *as, dma_addr_t addr, + uint8_t c, dma_addr_t len); +/** + * address_space_map: Map a physical memory region into a host virtual address. + * + * May map a subset of the requested range, given by and returned in @plen. + * May return %NULL and set *@plen to zero(0), if resources needed to perform + * the mapping are exhausted. + * Use only for reads OR writes - not for read-modify-write operations. + * + * @as: #AddressSpace to be accessed + * @addr: address within that address space + * @len: pointer to length of buffer; updated on return + * @dir: indicates the transfer direction + */ static inline void *dma_memory_map(AddressSpace *as, dma_addr_t addr, dma_addr_t *len, DMADirection dir) @@ -138,6 +205,20 @@ static inline void *dma_memory_map(AddressSpace *as, return p; } +/** + * address_space_unmap: Unmaps a memory region previously mapped + * by dma_memory_map() + * + * Will also mark the memory as dirty if @dir == %DMA_DIRECTION_FROM_DEVICE. + * @access_len gives the amount of memory that was actually read or written + * by the caller. + * + * @as: #AddressSpace used + * @buffer: host pointer as returned by address_space_map() + * @len: buffer length as returned by address_space_map() + * @dir: indicates the transfer direction + * @access_len: amount of data actually transferred + */ static inline void dma_memory_unmap(AddressSpace *as, void *buffer, dma_addr_t len, DMADirection dir, dma_addr_t access_len) |