In preparation of rework of the Xen PT, the logic to update an entry
in moved out in a separate function.
Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Andrii Anisov <andrii_anisov@epam.com>
---
Changes in v2:
- Add Andrii's reviewed-by
---
xen/arch/arm/mm.c | 140 +++++++++++++++++++++++++++++-------------------------
1 file changed, 74 insertions(+), 66 deletions(-)
diff --git a/xen/arch/arm/mm.c b/xen/arch/arm/mm.c
index 36e22fc9ad..f956aa6399 100644
--- a/xen/arch/arm/mm.c
+++ b/xen/arch/arm/mm.c
@@ -968,6 +968,76 @@ enum xenmap_operation {
RESERVE
};
+static int xen_pt_update_entry(enum xenmap_operation op, unsigned long addr,
+ mfn_t mfn, unsigned int flags)
+{
+ lpae_t pte, *entry;
+ lpae_t *third = NULL;
+
+ entry = &xen_second[second_linear_offset(addr)];
+ if ( !lpae_is_valid(*entry) || !lpae_is_table(*entry, 2) )
+ {
+ int rc = create_xen_table(entry);
+ if ( rc < 0 ) {
+ printk("%s: L2 failed\n", __func__);
+ return rc;
+ }
+ }
+
+ BUG_ON(!lpae_is_valid(*entry));
+
+ third = mfn_to_virt(lpae_get_mfn(*entry));
+ entry = &third[third_table_offset(addr)];
+
+ switch ( op ) {
+ case INSERT:
+ case RESERVE:
+ if ( lpae_is_valid(*entry) )
+ {
+ printk("%s: trying to replace an existing mapping addr=%lx mfn=%"PRI_mfn"\n",
+ __func__, addr, mfn_x(mfn));
+ return -EINVAL;
+ }
+ if ( op == RESERVE )
+ break;
+ pte = mfn_to_xen_entry(mfn, PAGE_AI_MASK(flags));
+ pte.pt.ro = PAGE_RO_MASK(flags);
+ pte.pt.xn = PAGE_XN_MASK(flags);
+ BUG_ON(!pte.pt.ro && !pte.pt.xn);
+ pte.pt.table = 1;
+ write_pte(entry, pte);
+ break;
+ case MODIFY:
+ case REMOVE:
+ if ( !lpae_is_valid(*entry) )
+ {
+ printk("%s: trying to %s a non-existing mapping addr=%lx\n",
+ __func__, op == REMOVE ? "remove" : "modify", addr);
+ return -EINVAL;
+ }
+ if ( op == REMOVE )
+ pte.bits = 0;
+ else
+ {
+ pte = *entry;
+ pte.pt.ro = PAGE_RO_MASK(flags);
+ pte.pt.xn = PAGE_XN_MASK(flags);
+ if ( !pte.pt.ro && !pte.pt.xn )
+ {
+ printk("%s: Incorrect combination for addr=%lx\n",
+ __func__, addr);
+ return -EINVAL;
+ }
+ }
+ write_pte(entry, pte);
+ break;
+ default:
+ BUG();
+ }
+
+ return 0;
+}
+
static DEFINE_SPINLOCK(xen_pt_lock);
static int xen_pt_update(enum xenmap_operation op,
@@ -978,78 +1048,16 @@ static int xen_pt_update(enum xenmap_operation op,
{
int rc = 0;
unsigned long addr = virt, addr_end = addr + nr_mfns * PAGE_SIZE;
- lpae_t pte, *entry;
- lpae_t *third = NULL;
spin_lock(&xen_pt_lock);
for(; addr < addr_end; addr += PAGE_SIZE, mfn = mfn_add(mfn, 1))
{
- entry = &xen_second[second_linear_offset(addr)];
- if ( !lpae_is_valid(*entry) || !lpae_is_table(*entry, 2) )
- {
- rc = create_xen_table(entry);
- if ( rc < 0 ) {
- printk("%s: L2 failed\n", __func__);
- goto out;
- }
- }
-
- BUG_ON(!lpae_is_valid(*entry));
-
- third = mfn_to_virt(lpae_get_mfn(*entry));
- entry = &third[third_table_offset(addr)];
-
- switch ( op ) {
- case INSERT:
- case RESERVE:
- if ( lpae_is_valid(*entry) )
- {
- printk("%s: trying to replace an existing mapping addr=%lx mfn=%"PRI_mfn"\n",
- __func__, addr, mfn_x(mfn));
- rc = -EINVAL;
- goto out;
- }
- if ( op == RESERVE )
- break;
- pte = mfn_to_xen_entry(mfn, PAGE_AI_MASK(flags));
- pte.pt.ro = PAGE_RO_MASK(flags);
- pte.pt.xn = PAGE_XN_MASK(flags);
- BUG_ON(!pte.pt.ro && !pte.pt.xn);
- pte.pt.table = 1;
- write_pte(entry, pte);
- break;
- case MODIFY:
- case REMOVE:
- if ( !lpae_is_valid(*entry) )
- {
- printk("%s: trying to %s a non-existing mapping addr=%lx\n",
- __func__, op == REMOVE ? "remove" : "modify", addr);
- rc = -EINVAL;
- goto out;
- }
- if ( op == REMOVE )
- pte.bits = 0;
- else
- {
- pte = *entry;
- pte.pt.ro = PAGE_RO_MASK(flags);
- pte.pt.xn = PAGE_XN_MASK(flags);
- if ( !pte.pt.ro && !pte.pt.xn )
- {
- printk("%s: Incorrect combination for addr=%lx\n",
- __func__, addr);
- rc = -EINVAL;
- goto out;
- }
- }
- write_pte(entry, pte);
- break;
- default:
- BUG();
- }
+ rc = xen_pt_update_entry(op, addr, mfn, flags);
+ if ( rc )
+ break;
}
-out:
+
/*
* Flush the TLBs even in case of failure because we may have
* partially modified the PT. This will prevent any unexpected
--
2.11.0
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-develOn Tue, 14 May 2019, Julien Grall wrote:
> In preparation of rework of the Xen PT, the logic to update an entry
> in moved out in a separate function.
>
> Signed-off-by: Julien Grall <julien.grall@arm.com>
> Reviewed-by: Andrii Anisov <andrii_anisov@epam.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
> ---
> Changes in v2:
> - Add Andrii's reviewed-by
> ---
> xen/arch/arm/mm.c | 140 +++++++++++++++++++++++++++++-------------------------
> 1 file changed, 74 insertions(+), 66 deletions(-)
>
> diff --git a/xen/arch/arm/mm.c b/xen/arch/arm/mm.c
> index 36e22fc9ad..f956aa6399 100644
> --- a/xen/arch/arm/mm.c
> +++ b/xen/arch/arm/mm.c
> @@ -968,6 +968,76 @@ enum xenmap_operation {
> RESERVE
> };
>
> +static int xen_pt_update_entry(enum xenmap_operation op, unsigned long addr,
> + mfn_t mfn, unsigned int flags)
> +{
> + lpae_t pte, *entry;
> + lpae_t *third = NULL;
> +
> + entry = &xen_second[second_linear_offset(addr)];
> + if ( !lpae_is_valid(*entry) || !lpae_is_table(*entry, 2) )
> + {
> + int rc = create_xen_table(entry);
> + if ( rc < 0 ) {
> + printk("%s: L2 failed\n", __func__);
> + return rc;
> + }
> + }
> +
> + BUG_ON(!lpae_is_valid(*entry));
> +
> + third = mfn_to_virt(lpae_get_mfn(*entry));
> + entry = &third[third_table_offset(addr)];
> +
> + switch ( op ) {
> + case INSERT:
> + case RESERVE:
> + if ( lpae_is_valid(*entry) )
> + {
> + printk("%s: trying to replace an existing mapping addr=%lx mfn=%"PRI_mfn"\n",
> + __func__, addr, mfn_x(mfn));
> + return -EINVAL;
> + }
> + if ( op == RESERVE )
> + break;
> + pte = mfn_to_xen_entry(mfn, PAGE_AI_MASK(flags));
> + pte.pt.ro = PAGE_RO_MASK(flags);
> + pte.pt.xn = PAGE_XN_MASK(flags);
> + BUG_ON(!pte.pt.ro && !pte.pt.xn);
> + pte.pt.table = 1;
> + write_pte(entry, pte);
> + break;
> + case MODIFY:
> + case REMOVE:
> + if ( !lpae_is_valid(*entry) )
> + {
> + printk("%s: trying to %s a non-existing mapping addr=%lx\n",
> + __func__, op == REMOVE ? "remove" : "modify", addr);
> + return -EINVAL;
> + }
> + if ( op == REMOVE )
> + pte.bits = 0;
> + else
> + {
> + pte = *entry;
> + pte.pt.ro = PAGE_RO_MASK(flags);
> + pte.pt.xn = PAGE_XN_MASK(flags);
> + if ( !pte.pt.ro && !pte.pt.xn )
> + {
> + printk("%s: Incorrect combination for addr=%lx\n",
> + __func__, addr);
> + return -EINVAL;
> + }
> + }
> + write_pte(entry, pte);
> + break;
> + default:
> + BUG();
> + }
> +
> + return 0;
> +}
> +
> static DEFINE_SPINLOCK(xen_pt_lock);
>
> static int xen_pt_update(enum xenmap_operation op,
> @@ -978,78 +1048,16 @@ static int xen_pt_update(enum xenmap_operation op,
> {
> int rc = 0;
> unsigned long addr = virt, addr_end = addr + nr_mfns * PAGE_SIZE;
> - lpae_t pte, *entry;
> - lpae_t *third = NULL;
>
> spin_lock(&xen_pt_lock);
>
> for(; addr < addr_end; addr += PAGE_SIZE, mfn = mfn_add(mfn, 1))
> {
> - entry = &xen_second[second_linear_offset(addr)];
> - if ( !lpae_is_valid(*entry) || !lpae_is_table(*entry, 2) )
> - {
> - rc = create_xen_table(entry);
> - if ( rc < 0 ) {
> - printk("%s: L2 failed\n", __func__);
> - goto out;
> - }
> - }
> -
> - BUG_ON(!lpae_is_valid(*entry));
> -
> - third = mfn_to_virt(lpae_get_mfn(*entry));
> - entry = &third[third_table_offset(addr)];
> -
> - switch ( op ) {
> - case INSERT:
> - case RESERVE:
> - if ( lpae_is_valid(*entry) )
> - {
> - printk("%s: trying to replace an existing mapping addr=%lx mfn=%"PRI_mfn"\n",
> - __func__, addr, mfn_x(mfn));
> - rc = -EINVAL;
> - goto out;
> - }
> - if ( op == RESERVE )
> - break;
> - pte = mfn_to_xen_entry(mfn, PAGE_AI_MASK(flags));
> - pte.pt.ro = PAGE_RO_MASK(flags);
> - pte.pt.xn = PAGE_XN_MASK(flags);
> - BUG_ON(!pte.pt.ro && !pte.pt.xn);
> - pte.pt.table = 1;
> - write_pte(entry, pte);
> - break;
> - case MODIFY:
> - case REMOVE:
> - if ( !lpae_is_valid(*entry) )
> - {
> - printk("%s: trying to %s a non-existing mapping addr=%lx\n",
> - __func__, op == REMOVE ? "remove" : "modify", addr);
> - rc = -EINVAL;
> - goto out;
> - }
> - if ( op == REMOVE )
> - pte.bits = 0;
> - else
> - {
> - pte = *entry;
> - pte.pt.ro = PAGE_RO_MASK(flags);
> - pte.pt.xn = PAGE_XN_MASK(flags);
> - if ( !pte.pt.ro && !pte.pt.xn )
> - {
> - printk("%s: Incorrect combination for addr=%lx\n",
> - __func__, addr);
> - rc = -EINVAL;
> - goto out;
> - }
> - }
> - write_pte(entry, pte);
> - break;
> - default:
> - BUG();
> - }
> + rc = xen_pt_update_entry(op, addr, mfn, flags);
> + if ( rc )
> + break;
> }
> -out:
> +
> /*
> * Flush the TLBs even in case of failure because we may have
> * partially modified the PT. This will prevent any unexpected
> --
> 2.11.0
>
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