Separate flag codes, make 32bits and 64bits accessible on both 64bit and 32bit platforms.

Signed-off-by: Gerd Zellweger <mail@gerdzellweger.com>

5 files changed, 97 insertions, 50 deletions

diff --git a/src/bits32/eflags.rs b/src/bits32/eflags.rs
new file mode 100644
index 0000000..d937d25
--- /dev/null
+++ b/src/bits32/eflags.rs
@@ -0,0 +1,73 @@
+//! Processor state stored in the EFLAGS register.
+
+use super::PrivilegeLevel;
+
+/// The EFLAGS register.
+bitflags! {
+    pub flags EFlags: u32 {
+        /// ID Flag (ID)
+        const FLAGS_ID = 1 << 21,
+        /// Virtual Interrupt Pending (VIP)
+        const FLAGS_VIP = 1 << 20,
+        /// Virtual Interrupt Flag (VIF)
+        const FLAGS_VIF = 1 << 19,
+        /// Alignment Check (AC)
+        const FLAGS_AC = 1 << 18,
+        /// Virtual-8086 Mode (VM)
+        const FLAGS_VM = 1 << 17,
+        /// Resume Flag (RF)
+        const FLAGS_RF = 1 << 16,
+        /// Nested Task (NT)
+        const FLAGS_NT = 1 << 14,
+        /// I/O Privilege Level (IOPL) 0
+        const FLAGS_IOPL0 = 0b00 << 12,
+        /// I/O Privilege Level (IOPL) 1
+        const FLAGS_IOPL1 = 0b01 << 12,
+        /// I/O Privilege Level (IOPL) 2
+        const FLAGS_IOPL2 = 0b10 << 12,
+        /// I/O Privilege Level (IOPL) 3
+        const FLAGS_IOPL3 = 0b11 << 12,
+        /// Overflow Flag (OF)
+        const FLAGS_OF = 1 << 11,
+        /// Direction Flag (DF)
+        const FLAGS_DF = 1 << 10,
+        /// Interrupt Enable Flag (IF)
+        const FLAGS_IF = 1 << 9,
+        /// Trap Flag (TF)
+        const FLAGS_TF = 1 << 8,
+        /// Sign Flag (SF)
+        const FLAGS_SF = 1 << 7,
+        /// Zero Flag (ZF)
+        const FLAGS_ZF = 1 << 6,
+        /// Auxiliary Carry Flag (AF)
+        const FLAGS_AF = 1 << 4,
+        /// Parity Flag (PF)
+        const FLAGS_PF = 1 << 2,
+        /// Bit 1 is always 1.
+        const FLAGS_A1 = 1 << 1,
+        /// Carry Flag (CF)
+        const FLAGS_CF = 1 << 0,
+    }
+}
+
+impl Flags {
+    /// Creates a new Flags entry. Ensures bit 1 is set.
+    pub const fn new() -> EFlags {
+        FLAGS_A1
+    }
+
+    /// Creates a new Flags with the given I/O privilege level.
+    pub const fn from_priv(iopl: PrivilegeLevel) -> EFlags {
+        EFlags { bits: (iopl as u32) << 12 }
+    }
+}
+
+pub unsafe fn read() -> EFlags {
+    let r: u32;
+    asm!("pushfl; popl $0" : "=r"(r) :: "memory");
+    EFlags::from_bits_truncate(r)
+}
+
+pub unsafe fn set(val: EFlags) {
+    asm!("pushl $0; popfl" :: "r"(val.bits()) : "memory" "flags");
+}
diff --git a/src/bits32/mod.rs b/src/bits32/mod.rs
index 2ffe79f..d4f76f6 100644
--- a/src/bits32/mod.rs
+++ b/src/bits32/mod.rs
@@ -1,4 +1,5 @@
 pub mod irq;
+pub mod eflags;
 pub mod segmentation;
 pub mod task;
 
diff --git a/src/bits64/mod.rs b/src/bits64/mod.rs
index 7409435..d72b732 100644
--- a/src/bits64/mod.rs
+++ b/src/bits64/mod.rs
@@ -16,6 +16,7 @@ macro_rules! check_flag {
 }
 
 pub mod irq;
+pub mod rflags;
 pub mod paging;
 pub mod segmentation;
 pub mod task;
diff --git a/src/flags.rs b/src/bits64/rflags.rs
index 46013a8..69e85ee 100644
--- a/src/flags.rs
+++ b/src/bits64/rflags.rs
@@ -1,11 +1,15 @@
-//! Processor state stored in the FLAGS, EFLAGS, or RFLAGS register.
+//! Processor state stored in the RFLAGS register.
+//!
+//! In 64-bit mode, EFLAGS is extended to 64 bits and called RFLAGS. 
+//! The upper 32 bits of RFLAGS register is reserved. 
+//! The lower 32 bits of RFLAGS is the same as EFLAGS.
 
 use ::PrivilegeLevel;
 
-/// The RFLAGS register. All variants are backwards compatable so only one
-/// bitflags struct needed.
+/// The RFLAGS register.
+/// This is duplicated code from bits32 eflags.rs.
 bitflags! {
-    pub flags Flags: usize {
+    pub flags RFlags: u64 {
         /// ID Flag (ID)
         const FLAGS_ID = 1 << 21,
         /// Virtual Interrupt Pending (VIP)
@@ -21,13 +25,13 @@ bitflags! {
         /// Nested Task (NT)
         const FLAGS_NT = 1 << 14,
         /// I/O Privilege Level (IOPL) 0
-        const FLAGS_IOPL0 = 0 << 12,
+        const FLAGS_IOPL0 = 0b00 << 12,
         /// I/O Privilege Level (IOPL) 1
-        const FLAGS_IOPL1 = 1 << 12,
+        const FLAGS_IOPL1 = 0b01 << 12,
         /// I/O Privilege Level (IOPL) 2
-        const FLAGS_IOPL2 = 2 << 12,
+        const FLAGS_IOPL2 = 0b10 << 12,
         /// I/O Privilege Level (IOPL) 3
-        const FLAGS_IOPL3 = 3 << 12,
+        const FLAGS_IOPL3 = 0b11 << 12,
         /// Overflow Flag (OF)
         const FLAGS_OF = 1 << 11,
         /// Direction Flag (DF)
@@ -51,52 +55,24 @@ bitflags! {
     }
 }
 
-impl Flags {
+impl RFlags {
     /// Creates a new Flags entry. Ensures bit 1 is set.
-    pub const fn new() -> Flags {
+    pub const fn new() -> RFlags {
         FLAGS_A1
     }
 
     /// Creates a new Flags with the given I/O privilege level.
-    pub const fn from_priv(iopl: PrivilegeLevel) -> Flags {
-        Flags { bits: (iopl as usize) << 12 }
+    pub const fn from_priv(iopl: PrivilegeLevel) -> RFlags {
+        RFlags { bits: (iopl as u64) << 12 }
     }
 }
 
-pub fn flags() -> Flags {
-
-    #[cfg(target_arch="x86")]
-    #[inline(always)]
-    unsafe fn inner() -> Flags {
-        let r: usize;
-        asm!("pushfl; popl $0" : "=r"(r) :: "memory");
-        Flags::from_bits_truncate(r)
-    }
-
-    #[cfg(target_arch="x86_64")]
-    #[inline(always)]
-    unsafe fn inner() -> Flags {
-        let r: usize;
-        asm!("pushfq; popq $0" : "=r"(r) :: "memory");
-        Flags::from_bits_truncate(r)
-    }
-
-    unsafe { inner() }
+pub unsafe fn flags() -> RFlags {
+    let r: u64;
+    asm!("pushfq; popq $0" : "=r"(r) :: "memory");
+    RFlags::from_bits_truncate(r)
 }
 
-pub fn set(val: Flags) {
-
-    #[cfg(target_arch="x86")]
-    #[inline(always)]
-    unsafe fn inner(val: Flags) {
-        asm!("pushl $0; popfl" :: "r"(val.bits()) : "memory" "flags");
-    }
-
-    #[cfg(target_arch="x86_64")]
-    #[inline(always)]
-    unsafe fn inner(val: Flags) {
-        asm!("pushq $0; popfq" :: "r"(val.bits()) : "memory" "flags");
-    }
-
-    unsafe { inner(val) }
+pub unsafe fn set(val: RFlags) {
+    asm!("pushq $0; popfq" :: "r"(val.bits()) : "memory" "flags");
 }
diff --git a/src/lib.rs b/src/lib.rs
index aff1cfb..1b08585 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -12,10 +12,7 @@ extern crate raw_cpuid;
 #[macro_use]
 extern crate phf;
 
-#[cfg(target_arch="x86")]
 pub mod bits32;
-
-#[cfg(target_arch="x86_64")]
 pub mod bits64;
 
 pub mod control_regs;
@@ -25,7 +22,6 @@ pub mod io;
 pub mod irq;
 pub mod msr;
 pub mod paging;
-pub mod flags;
 pub mod segmentation;
 pub mod task;
 pub mod tlb;