From 753ed9c95c37d058e50e7d42bbe296ee0bf6670d Mon Sep 17 00:00:00 2001 From: Joseph Salisbury Date: Fri, 16 Apr 2021 17:43:03 -0700 Subject: drivers: hv: Create a consistent pattern for checking Hyper-V hypercall status There is not a consistent pattern for checking Hyper-V hypercall status. Existing code uses a number of variants. The variants work, but a consistent pattern would improve the readability of the code, and be more conformant to what the Hyper-V TLFS says about hypercall status. Implemented new helper functions hv_result(), hv_result_success(), and hv_repcomp(). Changed the places where hv_do_hypercall() and related variants are used to use the helper functions. Signed-off-by: Joseph Salisbury Reviewed-by: Michael Kelley Link: https://lore.kernel.org/r/1618620183-9967-2-git-send-email-joseph.salisbury@linux.microsoft.com Signed-off-by: Wei Liu --- include/asm-generic/mshyperv.h | 25 ++++++++++++++++++++----- 1 file changed, 20 insertions(+), 5 deletions(-) (limited to 'include/asm-generic/mshyperv.h') diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h index 301db9adc82d..9a000ba2bb75 100644 --- a/include/asm-generic/mshyperv.h +++ b/include/asm-generic/mshyperv.h @@ -41,6 +41,24 @@ extern struct ms_hyperv_info ms_hyperv; extern u64 hv_do_hypercall(u64 control, void *inputaddr, void *outputaddr); extern u64 hv_do_fast_hypercall8(u16 control, u64 input8); +/* Helper functions that provide a consistent pattern for checking Hyper-V hypercall status. */ +static inline int hv_result(u64 status) +{ + return status & HV_HYPERCALL_RESULT_MASK; +} + +static inline bool hv_result_success(u64 status) +{ + return hv_result(status) == HV_STATUS_SUCCESS; +} + +static inline unsigned int hv_repcomp(u64 status) +{ + /* Bits [43:32] of status have 'Reps completed' data. */ + return (status & HV_HYPERCALL_REP_COMP_MASK) >> + HV_HYPERCALL_REP_COMP_OFFSET; +} + /* * Rep hypercalls. Callers of this functions are supposed to ensure that * rep_count and varhead_size comply with Hyper-V hypercall definition. @@ -57,12 +75,10 @@ static inline u64 hv_do_rep_hypercall(u16 code, u16 rep_count, u16 varhead_size, do { status = hv_do_hypercall(control, input, output); - if ((status & HV_HYPERCALL_RESULT_MASK) != HV_STATUS_SUCCESS) + if (!hv_result_success(status)) return status; - /* Bits 32-43 of status have 'Reps completed' data. */ - rep_comp = (status & HV_HYPERCALL_REP_COMP_MASK) >> - HV_HYPERCALL_REP_COMP_OFFSET; + rep_comp = hv_repcomp(status); control &= ~HV_HYPERCALL_REP_START_MASK; control |= (u64)rep_comp << HV_HYPERCALL_REP_START_OFFSET; @@ -87,7 +103,6 @@ static inline __u64 generate_guest_id(__u64 d_info1, __u64 kernel_version, return guest_id; } - /* Free the message slot and signal end-of-message if required */ static inline void vmbus_signal_eom(struct hv_message *msg, u32 old_msg_type) { -- cgit v1.2.1