[PATCH v3 7/7] firmware: arm_ffa: Add support for MEM_* interfaces
Jens Wiklander
jens.wiklander at linaro.org
Fri Dec 11 05:54:40 EST 2020
On Fri, Dec 4, 2020 at 1:11 PM Sudeep Holla <sudeep.holla at arm.com> wrote:
>
> Most of the MEM_* APIs share the same parameters, so they can be
> generalised. Currently only MEM_SHARE is implemented and the user space
> interface for that is not added yet.
>
> Signed-off-by: Sudeep Holla <sudeep.holla at arm.com>
> ---
> drivers/firmware/arm_ffa/driver.c | 180 ++++++++++++++++++++++++++++++
> include/linux/arm_ffa.h | 149 +++++++++++++++++++++++++
> 2 files changed, 329 insertions(+)
>
> diff --git a/drivers/firmware/arm_ffa/driver.c b/drivers/firmware/arm_ffa/driver.c
> index 3e4ba841dbf8..92a0bf542f18 100644
> --- a/drivers/firmware/arm_ffa/driver.c
> +++ b/drivers/firmware/arm_ffa/driver.c
> @@ -28,7 +28,9 @@
> #include <linux/io.h>
> #include <linux/kernel.h>
> #include <linux/module.h>
> +#include <linux/mm.h>
> #include <linux/of.h>
> +#include <linux/scatterlist.h>
> #include <linux/slab.h>
> #include <linux/uuid.h>
>
> @@ -306,6 +308,177 @@ static int ffa_msg_send_direct_req(u16 src_id, u16 dst_id,
> return 0;
> }
>
> +static int ffa_mem_first_frag(u32 func_id, phys_addr_t buf, u32 buf_sz,
> + u32 frag_len, u32 len, u64 *handle)
> +{
> + ffa_res_t ret;
> +
> + ret = invoke_ffa_fn(func_id, len, frag_len, buf, buf_sz, 0, 0, 0);
> +
> + while (ret.a0 == FFA_MEM_OP_PAUSE)
> + ret = invoke_ffa_fn(FFA_MEM_OP_RESUME, ret.a1, ret.a2,
> + 0, 0, 0, 0, 0);
> + if (ret.a0 == FFA_ERROR)
> + return ffa_to_linux_errno((int)ret.a2);
> +
> + if (ret.a0 != FFA_SUCCESS)
> + return -EOPNOTSUPP;
> +
> + if (handle)
> + *handle = PACK_HANDLE(ret.a3, ret.a2);
ret.a2 are the lower 32bit and ret.a3 the higher 32bits according to
5.10.2 Memory region handle
> +
> + return frag_len;
> +}
> +
> +static int ffa_mem_next_frag(u64 handle, u32 frag_len)
> +{
> + ffa_res_t ret;
> +
> + ret = invoke_ffa_fn(FFA_MEM_FRAG_TX, HANDLE_LOW(handle),
> + HANDLE_HIGH(handle), frag_len, 0, 0, 0, 0);
> +
> + while (ret.a0 == FFA_MEM_OP_PAUSE)
> + ret = invoke_ffa_fn(FFA_MEM_OP_RESUME, ret.a1, ret.a2,
> + 0, 0, 0, 0, 0);
> + if (ret.a0 == FFA_ERROR)
> + return ffa_to_linux_errno((int)ret.a2);
> +
> + if (ret.a0 != FFA_MEM_FRAG_RX)
> + return -EOPNOTSUPP;
> +
> + return ret.a3;
> +}
> +
> +static int
> +ffa_transmit_fragment(u32 func_id, phys_addr_t buf, u32 buf_sz, u32 frag_len,
> + u32 len, u64 *handle, bool first)
> +{
> + if (!first)
> + return ffa_mem_next_frag(*handle, frag_len);
> +
> + return ffa_mem_first_frag(func_id, buf, buf_sz, frag_len,
> + len, handle);
> +}
> +
> +static u32 ffa_get_num_pages_sg(struct scatterlist *sg)
> +{
> + u32 num_pages = 0;
> +
> + do {
> + num_pages += sg->length / FFA_PAGE_SIZE;
> + } while ((sg = sg_next(sg)));
> +
> + return num_pages;
> +}
> +
> +static int
> +ffa_setup_and_transmit(u32 func_id, void *buffer, u32 max_fragsize,
> + struct ffa_mem_ops_args *args)
> +{
> + int rc = 0;
> + bool first = true;
> + phys_addr_t addr = 0;
> + struct ffa_composite_mem_region *composite;
> + struct ffa_mem_region_addr_range *constituents;
> + struct ffa_mem_region_attributes *ep_mem_access;
> + struct ffa_mem_region *mem_region = buffer;
> + u32 idx, frag_len, length, num_entries = sg_nents(args->sg);
> + u32 buf_sz = max_fragsize / FFA_PAGE_SIZE;
This must be zero following the same logic as for addr, see 11.3 FFA_MEM_SHARE
> +
> + mem_region->tag = args->tag;
> + mem_region->flags = args->flags;
> + mem_region->sender_id = drv_info->vm_id;
> + mem_region->attributes = FFA_MEM_NORMAL | FFA_MEM_WRITE_BACK |
> + FFA_MEM_INNER_SHAREABLE;
> + ep_mem_access = &mem_region->ep_mem_access[0];
> +
> + for (idx = 0; idx < args->nattrs; idx++, ep_mem_access++) {
> + ep_mem_access->receiver = args->attrs[idx].receiver;
> + ep_mem_access->attrs = args->attrs[idx].attrs;
> + ep_mem_access->composite_off = COMPOSITE_OFFSET(args->nattrs);
> + }
> + mem_region->ep_count = args->nattrs;
> +
> + composite = buffer + COMPOSITE_OFFSET(args->nattrs);
> + composite->total_pg_cnt = ffa_get_num_pages_sg(args->sg);
> + composite->addr_range_cnt = num_entries;
> +
> + length = COMPOSITE_CONSTITUENTS_OFFSET(args->nattrs, num_entries);
> + frag_len = COMPOSITE_CONSTITUENTS_OFFSET(args->nattrs, 0);
> + if (frag_len > max_fragsize)
> + return -ENXIO;
> +
> + if (!args->use_txbuf)
> + addr = virt_to_phys(buffer);
> +
> + constituents = buffer + frag_len;
> + idx = 0;
> + do {
> + if (frag_len == max_fragsize) {
> + rc = ffa_transmit_fragment(func_id, addr, buf_sz,
> + frag_len, length,
> + args->g_handle, first);
> + if (rc < 0)
> + return -ENXIO;
> +
> + first = false;
> + idx = 0;
> + frag_len = 0;
> + constituents = buffer;
> + }
> +
> + if ((void *)constituents - buffer > max_fragsize) {
> + pr_err("Memory Region Fragment > Tx Buffer size\n");
> + return -EFAULT;
> + }
> +
> + constituents->address = sg_phys(args->sg);
> + constituents->pg_cnt = args->sg->length / FFA_PAGE_SIZE;
> + constituents++;
> + frag_len += sizeof(struct ffa_mem_region_addr_range);
> + } while ((args->sg = sg_next(args->sg)));
> +
> + return ffa_transmit_fragment(func_id, addr, buf_sz, frag_len,
> + length, args->g_handle, first);
> +}
> +
> +static int ffa_memory_ops(u32 func_id, struct ffa_mem_ops_args *args)
> +{
> + int ret;
> + void *buffer;
> +
> + if (!args->use_txbuf) {
> + buffer = alloc_pages_exact(RXTX_BUFFER_SIZE, GFP_KERNEL);
> + if (!buffer)
> + return -ENOMEM;
> + } else {
> + buffer = drv_info->tx_buffer;
> + mutex_lock(&drv_info->tx_lock);
> + }
> +
> + ret = ffa_setup_and_transmit(func_id, buffer, RXTX_BUFFER_SIZE, args);
> +
> + if (args->use_txbuf)
> + mutex_unlock(&drv_info->tx_lock);
> + else
> + free_pages_exact(buffer, RXTX_BUFFER_SIZE);
> +
> + return ret < 0 ? ret : 0;
> +}
> +
> +static int ffa_memory_reclaim(u64 g_handle, u32 flags)
> +{
> + ffa_res_t ret;
> +
> + ret = invoke_ffa_fn(FFA_MEM_RECLAIM, HANDLE_LOW(g_handle),
> + HANDLE_HIGH(g_handle), flags, 0, 0, 0, 0);
> +
> + if (ret.a0 == FFA_ERROR)
> + return ffa_to_linux_errno((int)ret.a2);
> +
> + return 0;
> +}
> +
> static u32 ffa_api_version_get(void)
> {
> return drv_info->version;
> @@ -331,11 +504,18 @@ static int ffa_sync_send_receive(struct ffa_device *dev, u16 ep,
> return ffa_msg_send_direct_req(dev->vm_id, ep, data);
> }
>
> +static int ffa_memory_share(struct ffa_mem_ops_args *args)
> +{
> + return ffa_memory_ops(FFA_FN_NATIVE(MEM_SHARE), args);
> +}
> +
> static const struct ffa_dev_ops ffa_ops = {
> .api_version_get = ffa_api_version_get,
> .partition_id_get = ffa_partition_id_get,
> .partition_info_get = ffa_partition_info_get,
> .sync_send_receive = ffa_sync_send_receive,
> + .memory_reclaim = ffa_memory_reclaim,
> + .memory_share = ffa_memory_share,
> };
>
> const struct ffa_dev_ops *ffa_dev_ops_get(struct ffa_device *dev)
> diff --git a/include/linux/arm_ffa.h b/include/linux/arm_ffa.h
> index 8604c48289ce..67e3180e7097 100644
> --- a/include/linux/arm_ffa.h
> +++ b/include/linux/arm_ffa.h
> @@ -109,6 +109,153 @@ struct ffa_send_direct_data {
> unsigned long data4;
> };
>
> +struct ffa_mem_region_addr_range {
> + /* The base IPA of the constituent memory region, aligned to 4 kiB */
> + u64 address;
> + /* The number of 4 kiB pages in the constituent memory region. */
> + u32 pg_cnt;
> + u32 reserved;
> +};
> +
> +struct ffa_composite_mem_region {
> + /*
> + * The total number of 4 kiB pages included in this memory region. This
> + * must be equal to the sum of page counts specified in each
> + * `struct ffa_mem_region_addr_range`.
> + */
> + u32 total_pg_cnt;
> + /* The number of constituents included in this memory region range */
> + u32 addr_range_cnt;
> + u64 reserved;
> + /** An array of `addr_range_cnt` memory region constituents. */
> + struct ffa_mem_region_addr_range constituents[];
> +};
> +
> +struct ffa_mem_region_attributes {
> + /* The ID of the VM to which the memory is being given or shared. */
> + u16 receiver;
> + /*
> + * The permissions with which the memory region should be mapped in the
> + * receiver's page table.
> + */
> +#define FFA_MEM_EXEC BIT(3)
> +#define FFA_MEM_NO_EXEC BIT(2)
> +#define FFA_MEM_RW BIT(1)
> +#define FFA_MEM_RO BIT(0)
> + u8 attrs;
> + /*
> + * Flags used during FFA_MEM_RETRIEVE_REQ and FFA_MEM_RETRIEVE_RESP
> + * for memory regions with multiple borrowers.
> + */
> +#define FFA_MEM_RETRIEVE_SELF_BORROWER BIT(0)
> + u8 flag;
> + u32 composite_off;
> + /*
> + * Offset in bytes from the start of the outer `ffa_memory_region` to
> + * an `struct ffa_mem_region_addr_range`.
> + */
> + u64 reserved;
> +};
> +
> +struct ffa_mem_region {
> + /* The ID of the VM/owner which originally sent the memory region */
> + u16 sender_id;
> +#define FFA_MEM_NORMAL BIT(5)
> +#define FFA_MEM_DEVICE BIT(4)
> +
> +#define FFA_MEM_WRITE_BACK (3 << 2)
> +#define FFA_MEM_NON_CACHEABLE (1 << 2)
> +
> +#define FFA_DEV_nGnRnE (0 << 2)
> +#define FFA_DEV_nGnRE (1 << 2)
> +#define FFA_DEV_nGRE (2 << 2)
> +#define FFA_DEV_GRE (3 << 2)
> +
> +#define FFA_MEM_NON_SHAREABLE (0)
> +#define FFA_MEM_OUTER_SHAREABLE (2)
> +#define FFA_MEM_INNER_SHAREABLE (3)
> + u8 attributes;
> + u8 reserved_0;
> +/*
> + * Clear memory region contents after unmapping it from the sender and
> + * before mapping it for any receiver.
> + */
> +#define FFA_MEM_CLEAR BIT(0)
> +/*
> + * Whether the hypervisor may time slice the memory sharing or retrieval
> + * operation.
> + */
> +#define FFA_TIME_SLICE_ENABLE BIT(1)
> +
> +/*
> + * Whether the hypervisor should clear the memory region before the receiver
> + * relinquishes it or is aborted.
> + */
> +#define FFA_MEM_CLEAR_BEFORE_RELINQUISH BIT(0)
> +/*
> + * Whether the hypervisor should clear the memory region after the receiver
> + * relinquishes it or is aborted.
> + */
> +#define FFA_MEM_CLEAR_AFTER_RELINQUISH BIT(2)
> +
> +#define FFA_MEM_RETRIEVE_TYPE_IN_RESP (0 << 3)
> +#define FFA_MEM_RETRIEVE_TYPE_SHARE (1 << 3)
> +#define FFA_MEM_RETRIEVE_TYPE_LEND (2 << 3)
> +#define FFA_MEM_RETRIEVE_TYPE_DONATE (3 << 3)
> +
> +#define FFA_MEM_RETRIEVE_ADDR_ALIGN_HINT BIT(9)
> +#define FFA_MEM_RETRIEVE_ADDR_ALIGN(x) ((x) << 5)
> + /* Flags to control behaviour of the transaction. */
> + u32 flags;
> +#define HANDLE_LOW_MASK GENMASK_ULL(31, 0)
> +#define HANDLE_HIGH_MASK GENMASK_ULL(63, 32)
> +#define HANDLE_LOW(x) (u32)(FIELD_GET(HANDLE_LOW_MASK, (x)))
> +#define HANDLE_HIGH(x) (u32)(FIELD_GET(HANDLE_HIGH_MASK, (x)))
> +
> +#define PACK_HANDLE(l, h) \
> + (FIELD_PREP(HANDLE_LOW_MASK, (l)) | FIELD_PREP(HANDLE_HIGH_MASK, (h)))
> + /*
> + * A globally-unique ID assigned by the hypervisor for a region
> + * of memory being sent between VMs.
> + */
> + u64 handle;
> + /*
> + * An implementation defined value associated with the receiver and the
> + * memory region.
> + */
> + u64 tag;
> + u32 reserved_1;
> + /*
> + * The number of `ffa_mem_region_attributes` entries included in this
> + * transaction.
> + */
> + u32 ep_count;
> + /*
> + * An array of endpoint memory access descriptors.
> + * Each one specifies a memory region offset, an endpoint and the
> + * attributes with which this memory region should be mapped in that
> + * endpoint's page table.
> + */
> + struct ffa_mem_region_attributes ep_mem_access[];
> +};
> +
> +#define COMPOSITE_OFFSET(x) \
> + (offsetof(struct ffa_mem_region, ep_mem_access[x]))
> +#define CONSTITUENTS_OFFSET(x) \
> + (offsetof(struct ffa_composite_mem_region, constituents[x]))
> +#define COMPOSITE_CONSTITUENTS_OFFSET(x, y) \
> + (COMPOSITE_OFFSET(x) + CONSTITUENTS_OFFSET(y))
> +
> +struct ffa_mem_ops_args {
> + bool use_txbuf;
> + u64 tag;
> + u32 flags;
> + struct ffa_mem_region_attributes *attrs;
> + u32 nattrs;
> + struct scatterlist *sg;
> + u64 *g_handle;
It seems a bit inconvenient with a pointer instead of a value here.
Cheers,
Jens
> +};
> +
> struct ffa_dev_ops {
> u32 (*api_version_get)(void);
> u16 (*partition_id_get)(struct ffa_device *dev);
> @@ -116,6 +263,8 @@ struct ffa_dev_ops {
> struct ffa_partition_info *buffer);
> int (*sync_send_receive)(struct ffa_device *dev, u16 ep,
> struct ffa_send_direct_data *data);
> + int (*memory_reclaim)(u64 g_handle, u32 flags);
> + int (*memory_share)(struct ffa_mem_ops_args *args);
> };
>
> #endif /* _LINUX_ARM_FFA_H */
> --
> 2.25.1
>
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