diff options
Diffstat (limited to 'arch/arm64/kernel/fpsimd.c')
-rw-r--r-- | arch/arm64/kernel/fpsimd.c | 55 |
1 files changed, 45 insertions, 10 deletions
diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c index c7531b85b303..e7733fb19388 100644 --- a/arch/arm64/kernel/fpsimd.c +++ b/arch/arm64/kernel/fpsimd.c @@ -300,6 +300,32 @@ static void fpsimd_to_sve(struct task_struct *task) sizeof(fst->vregs[i])); } +/* + * Transfer the SVE state in task->thread.sve_state to + * task->thread.fpsimd_state. + * + * Task can be a non-runnable task, or current. In the latter case, + * softirqs (and preemption) must be disabled. + * task->thread.sve_state must point to at least sve_state_size(task) + * bytes of allocated kernel memory. + * task->thread.sve_state must be up to date before calling this function. + */ +static void sve_to_fpsimd(struct task_struct *task) +{ + unsigned int vq; + void const *sst = task->thread.sve_state; + struct fpsimd_state *fst = &task->thread.fpsimd_state; + unsigned int i; + + if (!system_supports_sve()) + return; + + vq = sve_vq_from_vl(task->thread.sve_vl); + for (i = 0; i < 32; ++i) + memcpy(&fst->vregs[i], ZREG(sst, vq, i), + sizeof(fst->vregs[i])); +} + #ifdef CONFIG_ARM64_SVE /* @@ -501,9 +527,6 @@ void fpsimd_flush_thread(void) /* * Save the userland FPSIMD state of 'current' to memory, but only if the state * currently held in the registers does in fact belong to 'current' - * - * Currently, SVE tasks can't exist, so just WARN in that case. - * Subsequent patches will add full SVE support here. */ void fpsimd_preserve_current_state(void) { @@ -511,16 +534,23 @@ void fpsimd_preserve_current_state(void) return; local_bh_disable(); - - if (!test_thread_flag(TIF_FOREIGN_FPSTATE)) - fpsimd_save_state(¤t->thread.fpsimd_state); - - WARN_ON_ONCE(test_and_clear_thread_flag(TIF_SVE)); - + task_fpsimd_save(); local_bh_enable(); } /* + * Like fpsimd_preserve_current_state(), but ensure that + * current->thread.fpsimd_state is updated so that it can be copied to + * the signal frame. + */ +void fpsimd_signal_preserve_current_state(void) +{ + fpsimd_preserve_current_state(); + if (system_supports_sve() && test_thread_flag(TIF_SVE)) + sve_to_fpsimd(current); +} + +/* * Load the userland FPSIMD state of 'current' from memory, but only if the * FPSIMD state already held in the registers is /not/ the most recent FPSIMD * state of 'current' @@ -555,7 +585,12 @@ void fpsimd_update_current_state(struct fpsimd_state *state) local_bh_disable(); - fpsimd_load_state(state); + if (system_supports_sve() && test_thread_flag(TIF_SVE)) { + current->thread.fpsimd_state = *state; + fpsimd_to_sve(current); + } + task_fpsimd_load(); + if (test_and_clear_thread_flag(TIF_FOREIGN_FPSTATE)) { struct fpsimd_state *st = ¤t->thread.fpsimd_state; |