fix(signedness): Change variables signedness to match the operation

The flag -wextra forces comparisons and other operations to have elements
with the same signedness. In the commit, we change some variables types to
match the operations they are used, or cast them to the correct type.

Signed-off-by: Miguel Silva <[email protected]>

src/arch/armv8/armv8-r/mpu.c

@@ -157,7 +157,7 @@ static inline mem_attrs_t mpu_entry_attrs(struct mp_region* mpr)
 static mpid_t mpu_entry_allocate()
 {
     mpid_t reg_num = INVALID_MPID;
-    for (mpid_t i = 0; i < mpu_num_entries(); i++) {
+    for (mpid_t i = 0; i < (ssize_t)mpu_num_entries(); i++) {
         if (bitmap_get(cpu()->arch.profile.mpu.bitmap, i) == 0) {
             bitmap_set(cpu()->arch.profile.mpu.bitmap, i);
             reg_num = i;
@@ -546,7 +546,7 @@ void mpu_init()
     bitmap_clear_consecutive(cpu()->arch.profile.mpu.bitmap, 0, mpu_num_entries());
     list_init(&cpu()->arch.profile.mpu.order.list);
 
-    for (mpid_t mpid = 0; mpid < mpu_num_entries(); mpid++) {
+    for (mpid_t mpid = 0; mpid < (ssize_t)mpu_num_entries(); mpid++) {
         cpu()->arch.profile.mpu.order.node[mpid].mpid = mpid;
 
         if (mpu_entry_valid(mpid)) {

src/arch/armv8/vgicv3.c

@@ -25,7 +25,7 @@ bool vgic_int_has_other_target(struct vcpu* vcpu, struct vgic_int* interrupt)
     bool priv = gic_is_priv(interrupt->id);
     bool routed_here =
         !priv && !(interrupt->phys.route ^ (sysreg_mpidr_el1_read() & MPIDR_AFF_MSK));
-    bool route_valid = interrupt->phys.route != GICD_IROUTER_INV;
+    bool route_valid = interrupt->phys.route != (unsigned int)GICD_IROUTER_INV;
     bool any = !priv && vgic_broadcast(vcpu, interrupt);
     return any || (!routed_here && route_valid);
 }

src/arch/riscv/irqc/aia/vaplic.c

@@ -260,7 +260,7 @@ static void vaplic_update_hart(struct vcpu* vcpu, int16_t vhart_index)
         for (size_t i = 0; i < vaplic->idc_num; i++) {
             vaplic_update_hart_line(vcpu, (vcpuid_t)i);
         }
-    } else if (vhart_index < vaplic->idc_num) {
+    } else if ((uint16_t)vhart_index < vaplic->idc_num) {
         vaplic_update_hart_line(vcpu, (vcpuid_t)vhart_index);
     }
 }

src/arch/riscv/irqc/plic/vplic.c

@@ -29,7 +29,7 @@ static int vplic_vcntxt_to_pcntxt(struct vcpu* vcpu, int vcntxt_id)
 static bool vplic_vcntxt_valid(struct vcpu* vcpu, int vcntxt_id)
 {
     struct plic_cntxt vcntxt = plic_plat_id_to_cntxt(vcntxt_id);
-    return vcntxt_id < vcpu->vm->arch.vplic.cntxt_num && vcntxt.mode <= PRIV_S;
+    return (unsigned int)vcntxt_id < vcpu->vm->arch.vplic.cntxt_num && vcntxt.mode <= PRIV_S;
 }
 
 static bool vplic_get_pend(struct vcpu* vcpu, irqid_t id)

src/arch/riscv/mem.c

@@ -27,7 +27,7 @@ static inline void as_map_physical_identity(struct addr_space* as)
         size_t num_entries = ((top - base - 1) / lvl_size) + 1;
 
         paddr_t addr = base;
-        for (int j = 0; j < num_entries; j++) {
+        for (unsigned int j = 0; j < num_entries; j++) {
             int index = pt_getpteindex_by_va(&as->pt, (vaddr_t)addr, lvl);
             pte_set(&pt[index], addr, PTE_SUPERPAGE, PTE_HYP_FLAGS);
             addr += lvl_size;

src/lib/bitmap.c

@@ -14,10 +14,10 @@ ssize_t bitmap_find_nth(bitmap_t* map, size_t size, size_t nth, size_t start, bo
     size_t count = 0;
     unsigned bit = set ? 1 : 0;
 
-    for (ssize_t i = start; i < size; i++) {
+    for (size_t i = start; i < size; i++) {
         if (bitmap_get(map, i) == bit) {
             if (++count == nth) {
-                return i;
+                return (ssize_t)i;
             }
         }
     }
@@ -69,10 +69,10 @@ ssize_t bitmap_find_consec(bitmap_t* map, size_t size, size_t start, size_t n, b
         return -1;
     }
 
-    while (i < size) {
+    while (i < (ssize_t)size) {
         // find the last (with n as maximum) contiguous set page
         count = bitmap_count_consecutive(map, size, i, n);
-        if (count < n) { // if didn't found enough n contiguous set pages
+        if (count < (ssize_t)n) { // if didn't found enough n contiguous set pages
             i += count;
             // find the last contiguous ~set page
             i += bitmap_count_consecutive(map, size, i, -1);
@@ -81,7 +81,7 @@ ssize_t bitmap_find_consec(bitmap_t* map, size_t size, size_t start, size_t n, b
         }
     }
 
-    if (i >= size) {
+    if (i >= (ssize_t)size) {
         i = -1;
     }