Hi Jens, On 13/04/2023 08:14, Jens Wiklander wrote:
+static uint32_t handle_rxtx_map(uint32_t fid, register_t tx_addr, + register_t rx_addr, uint32_t page_count) +{ + uint32_t ret = FFA_RET_INVALID_PARAMETERS; + struct domain *d = current->domain; + struct ffa_ctx *ctx = d->arch.tee; + struct page_info *tx_pg; + struct page_info *rx_pg; + p2m_type_t t; + void *rx; + void *tx; + + if ( !smccc_is_conv_64(fid) ) + { + /* + * Calls using the 32-bit calling convention must ignore the upper + * 32 bits in the argument registers. + */ + tx_addr &= UINT32_MAX; + rx_addr &= UINT32_MAX; + } + + if ( page_count > FFA_MAX_RXTX_PAGE_COUNT ) {
Coding style: if ( ... ) {
+ printk(XENLOG_ERR "ffa: RXTX_MAP: error: %u pages requested (limit %u)\n", + page_count, FFA_MAX_RXTX_PAGE_COUNT); + return FFA_RET_NOT_SUPPORTED; + } + + /* Already mapped */ + if ( ctx->rx ) + return FFA_RET_DENIED; + + tx_pg = get_page_from_gfn(d, gfn_x(gaddr_to_gfn(tx_addr)), &t, P2M_ALLOC);
I might be missing something. Here you only get the reference on one page. Per the value of FFA_MAX_RXTX_PAGE_COUNT, it looks like the buffer can be up to 32 pages.
Can you clarify?
+ if ( !tx_pg ) + return FFA_RET_INVALID_PARAMETERS; + /* Only normal RAM for now */ + if ( !p2m_is_ram(t) )
p2m_is_ram() would allow RAM page marked read-only in stage-2. Is it intended?
If not, then I think you want to use t != p2m_ram_rw.
+ goto err_put_tx_pg; + + rx_pg = get_page_from_gfn(d, gfn_x(gaddr_to_gfn(rx_addr)), &t, P2M_ALLOC); + if ( !tx_pg ) + goto err_put_tx_pg; + /* Only normal RAM for now */ + if ( !p2m_is_ram(t) )
Same here.
+ goto err_put_rx_pg; + + tx = __map_domain_page_global(tx_pg); + if ( !tx ) + goto err_put_rx_pg; + + rx = __map_domain_page_global(rx_pg); + if ( !rx ) + goto err_unmap_tx; + + ctx->rx = rx; + ctx->tx = tx; + ctx->rx_pg = rx_pg; + ctx->tx_pg = tx_pg; + ctx->page_count = page_count; + ctx->tx_is_free = true; + return FFA_RET_OK;
Cheers, -- Julien Grall