Stefano Stabellini | aa42aa1 | 2013-06-03 17:05:43 +0000 | [diff] [blame] | 1 | /****************************************************************************** |
| 2 | * hypercall.S |
| 3 | * |
| 4 | * Xen hypercall wrappers |
| 5 | * |
| 6 | * Stefano Stabellini <stefano.stabellini@eu.citrix.com>, Citrix, 2012 |
| 7 | * |
| 8 | * This program is free software; you can redistribute it and/or |
| 9 | * modify it under the terms of the GNU General Public License version 2 |
| 10 | * as published by the Free Software Foundation; or, when distributed |
| 11 | * separately from the Linux kernel or incorporated into other |
| 12 | * software packages, subject to the following license: |
| 13 | * |
| 14 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
| 15 | * of this source file (the "Software"), to deal in the Software without |
| 16 | * restriction, including without limitation the rights to use, copy, modify, |
| 17 | * merge, publish, distribute, sublicense, and/or sell copies of the Software, |
| 18 | * and to permit persons to whom the Software is furnished to do so, subject to |
| 19 | * the following conditions: |
| 20 | * |
| 21 | * The above copyright notice and this permission notice shall be included in |
| 22 | * all copies or substantial portions of the Software. |
| 23 | * |
| 24 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| 25 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| 26 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| 27 | * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| 28 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING |
| 29 | * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS |
| 30 | * IN THE SOFTWARE. |
| 31 | */ |
| 32 | |
| 33 | /* |
| 34 | * The Xen hypercall calling convention is very similar to the procedure |
| 35 | * call standard for the ARM 64-bit architecture: the first parameter is |
| 36 | * passed in x0, the second in x1, the third in x2, the fourth in x3 and |
| 37 | * the fifth in x4. |
| 38 | * |
| 39 | * The hypercall number is passed in x16. |
| 40 | * |
| 41 | * The return value is in x0. |
| 42 | * |
| 43 | * The hvc ISS is required to be 0xEA1, that is the Xen specific ARM |
| 44 | * hypercall tag. |
| 45 | * |
| 46 | * Parameter structs passed to hypercalls are laid out according to |
| 47 | * the ARM 64-bit EABI standard. |
| 48 | */ |
| 49 | |
| 50 | #include <linux/linkage.h> |
| 51 | #include <asm/assembler.h> |
Catalin Marinas | fd6b873 | 2016-07-05 12:25:15 +0100 | [diff] [blame] | 52 | #include <asm/uaccess.h> |
Stefano Stabellini | aa42aa1 | 2013-06-03 17:05:43 +0000 | [diff] [blame] | 53 | #include <xen/interface/xen.h> |
| 54 | |
| 55 | |
| 56 | #define XEN_IMM 0xEA1 |
| 57 | |
| 58 | #define HYPERCALL_SIMPLE(hypercall) \ |
| 59 | ENTRY(HYPERVISOR_##hypercall) \ |
| 60 | mov x16, #__HYPERVISOR_##hypercall; \ |
| 61 | hvc XEN_IMM; \ |
| 62 | ret; \ |
| 63 | ENDPROC(HYPERVISOR_##hypercall) |
| 64 | |
| 65 | #define HYPERCALL0 HYPERCALL_SIMPLE |
| 66 | #define HYPERCALL1 HYPERCALL_SIMPLE |
| 67 | #define HYPERCALL2 HYPERCALL_SIMPLE |
| 68 | #define HYPERCALL3 HYPERCALL_SIMPLE |
| 69 | #define HYPERCALL4 HYPERCALL_SIMPLE |
| 70 | #define HYPERCALL5 HYPERCALL_SIMPLE |
| 71 | |
| 72 | .text |
| 73 | |
| 74 | HYPERCALL2(xen_version); |
| 75 | HYPERCALL3(console_io); |
| 76 | HYPERCALL3(grant_table_op); |
| 77 | HYPERCALL2(sched_op); |
| 78 | HYPERCALL2(event_channel_op); |
| 79 | HYPERCALL2(hvm_op); |
| 80 | HYPERCALL2(memory_op); |
| 81 | HYPERCALL2(physdev_op); |
| 82 | HYPERCALL3(vcpu_op); |
Stefano Stabellini | 176455e | 2013-07-02 10:42:40 +0000 | [diff] [blame] | 83 | HYPERCALL1(tmem_op); |
Stefano Stabellini | 72d39c6 | 2015-11-23 10:37:12 +0000 | [diff] [blame] | 84 | HYPERCALL1(platform_op_raw); |
Ian Campbell | 5e40704 | 2014-04-17 13:57:37 +0100 | [diff] [blame] | 85 | HYPERCALL2(multicall); |
Juergen Gross | 4b5ae01 | 2016-07-06 07:00:29 +0200 | [diff] [blame] | 86 | HYPERCALL2(vm_assist); |
Stefano Stabellini | aa42aa1 | 2013-06-03 17:05:43 +0000 | [diff] [blame] | 87 | |
| 88 | ENTRY(privcmd_call) |
| 89 | mov x16, x0 |
| 90 | mov x0, x1 |
| 91 | mov x1, x2 |
| 92 | mov x2, x3 |
| 93 | mov x3, x4 |
| 94 | mov x4, x5 |
Catalin Marinas | fd6b873 | 2016-07-05 12:25:15 +0100 | [diff] [blame] | 95 | /* |
| 96 | * Privcmd calls are issued by the userspace. The kernel needs to |
| 97 | * enable access to TTBR0_EL1 as the hypervisor would issue stage 1 |
| 98 | * translations to user memory via AT instructions. Since AT |
| 99 | * instructions are not affected by the PAN bit (ARMv8.1), we only |
| 100 | * need the explicit uaccess_enable/disable if the TTBR0 PAN emulation |
| 101 | * is enabled (it implies that hardware UAO and PAN disabled). |
| 102 | */ |
| 103 | uaccess_ttbr0_enable x6, x7 |
Stefano Stabellini | aa42aa1 | 2013-06-03 17:05:43 +0000 | [diff] [blame] | 104 | hvc XEN_IMM |
Catalin Marinas | fd6b873 | 2016-07-05 12:25:15 +0100 | [diff] [blame] | 105 | |
| 106 | /* |
| 107 | * Disable userspace access from kernel once the hyp call completed. |
| 108 | */ |
| 109 | uaccess_ttbr0_disable x6 |
Stefano Stabellini | aa42aa1 | 2013-06-03 17:05:43 +0000 | [diff] [blame] | 110 | ret |
| 111 | ENDPROC(privcmd_call); |