From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marc Zyngier Subject: Re: [PATCH v7 21/24] KVM: arm64: vgic-its: Device table save/restore Date: Sun, 07 May 2017 14:30:57 +0100 Message-ID: <87zieoiyjy.fsf@on-the-bus.cambridge.arm.com> References: <1494084283-12723-1-git-send-email-eric.auger@redhat.com> <1494084283-12723-22-git-send-email-eric.auger@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: kvm@vger.kernel.org, Prasun.Kapoor@cavium.com, vijayak@caviumnetworks.com, andre.przywara@arm.com, quintela@redhat.com, dgilbert@redhat.com, bjsprakash.linux@gmail.com, Vijaya.Kumar@cavium.com, linux-arm-kernel@lists.infradead.org, pbonzini@redhat.com, kvmarm@lists.cs.columbia.edu, eric.auger.pro@gmail.com To: Eric Auger Return-path: In-Reply-To: <1494084283-12723-22-git-send-email-eric.auger@redhat.com> (Eric Auger's message of "Sat, 6 May 2017 17:24:40 +0200") List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu List-Id: kvm.vger.kernel.org On Sat, May 06 2017 at 4:24:40 pm BST, Eric Auger wrote: > This patch saves the device table entries into guest RAM. > Both flat table and 2 stage tables are supported. DeviceId > indexing is used. > > For each device listed in the device table, we also save > the translation table using the vgic_its_save/restore_itt > routines. Those functions will be implemented in a subsequent > patch. > > On restore, devices are re-allocated and their itt are > re-built. > > Signed-off-by: Eric Auger > > --- > v5 -> v6: > - accomodate vgic_its_alloc_device change of proto > - define bit fields for L1 entries > - s/handle_l1_entry/handle_l1_dte > - s/ite_esz/dte_esz in handle_l1_dte > - check BASER valid bit > - s/nb_eventid_bits/num_eventid_bits > - new convention for returned values > - itt functions implemented in subsequent patch > > v4 -> v5: > - sort the device list by deviceid on device table save > - use defines for shifts and masks > - use abi->dte_esz > - clatify entry sizes for L1 and L2 tables > > v3 -> v4: > - use the new proto for its_alloc_device > - compute_next_devid_offset, vgic_its_flush/restore_itt > become static in this patch > - change in the DTE entry format with the introduction of the > valid bit and next field width decrease; ittaddr encoded > on its full range > - fix handle_l1_entry entry handling > - correct vgic_its_table_restore error handling > > v2 -> v3: > - fix itt_addr bitmask in vgic_its_restore_dte > - addition of return 0 in vgic_its_restore_ite moved to > the ITE related patch > > v1 -> v2: > - use 8 byte format for DTE and ITE > - support 2 stage format > - remove kvm parameter > - ITT flush/restore moved in a separate patch > - use deviceid indexing > --- > virt/kvm/arm/vgic/vgic-its.c | 194 +++++++++++++++++++++++++++++++++++++++++-- > virt/kvm/arm/vgic/vgic.h | 10 +++ > 2 files changed, 199 insertions(+), 5 deletions(-) > > diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c > index 90afc83..3dea626 100644 > --- a/virt/kvm/arm/vgic/vgic-its.c > +++ b/virt/kvm/arm/vgic/vgic-its.c > @@ -23,6 +23,7 @@ > #include > #include > #include > +#include > > #include > > @@ -1735,7 +1736,8 @@ int vgic_its_attr_regs_access(struct kvm_device *dev, > return ret; > } > > -u32 compute_next_devid_offset(struct list_head *h, struct its_device *dev) > +static u32 compute_next_devid_offset(struct list_head *h, > + struct its_device *dev) > { > struct its_device *next; > u32 next_offset; > @@ -1789,8 +1791,8 @@ typedef int (*entry_fn_t)(struct vgic_its *its, u32 id, void *entry, > * Return: < 0 on error, 0 if last element was identified, 1 otherwise > * (the last element may not be found on second level tables) > */ > -int scan_its_table(struct vgic_its *its, gpa_t base, int size, int esz, > - int start_id, entry_fn_t fn, void *opaque) > +static int scan_its_table(struct vgic_its *its, gpa_t base, int size, int esz, > + int start_id, entry_fn_t fn, void *opaque) > { > void *entry = kzalloc(esz, GFP_KERNEL); > struct kvm *kvm = its->dev->kvm; > @@ -1825,13 +1827,171 @@ int scan_its_table(struct vgic_its *its, gpa_t base, int size, int esz, > return ret; > } > > +static int vgic_its_save_itt(struct vgic_its *its, struct its_device *device) > +{ > + return -ENXIO; > +} > + > +static int vgic_its_restore_itt(struct vgic_its *its, struct its_device *dev) > +{ > + return -ENXIO; > +} > + > +/** > + * vgic_its_save_dte - Save a device table entry at a given GPA > + * > + * @its: ITS handle > + * @dev: ITS device > + * @ptr: GPA > + */ > +static int vgic_its_save_dte(struct vgic_its *its, struct its_device *dev, > + gpa_t ptr, int dte_esz) > +{ > + struct kvm *kvm = its->dev->kvm; > + u64 val, itt_addr_field; > + u32 next_offset; > + > + itt_addr_field = dev->itt_addr >> 8; > + next_offset = compute_next_devid_offset(&its->device_list, dev); > + val = (1ULL << KVM_ITS_DTE_VALID_SHIFT | > + ((u64)next_offset << KVM_ITS_DTE_NEXT_SHIFT) | > + (itt_addr_field << KVM_ITS_DTE_ITTADDR_SHIFT) | > + (dev->num_eventid_bits - 1)); > + val = cpu_to_le64(val); > + return kvm_write_guest(kvm, ptr, &val, dte_esz); > +} > + > +/** > + * vgic_its_restore_dte - restore a device table entry > + * > + * @its: its handle > + * @id: device id the DTE corresponds to > + * @ptr: kernel VA where the 8 byte DTE is located > + * @opaque: unused > + * > + * Return: < 0 on error, 0 if the dte is the last one, id offset to the > + * next dte otherwise > + */ > +static int vgic_its_restore_dte(struct vgic_its *its, u32 id, > + void *ptr, void *opaque) > +{ > + struct its_device *dev; > + gpa_t itt_addr; > + u8 num_eventid_bits; > + u64 entry = *(u64 *)ptr; > + bool valid; > + u32 offset; > + int ret; > + > + entry = le64_to_cpu(entry); > + > + valid = entry >> KVM_ITS_DTE_VALID_SHIFT; > + num_eventid_bits = (entry & KVM_ITS_DTE_SIZE_MASK) + 1; > + itt_addr = ((entry & KVM_ITS_DTE_ITTADDR_MASK) > + >> KVM_ITS_DTE_ITTADDR_SHIFT) << 8; > + > + if (!valid) > + return 1; > + > + /* dte entry is valid */ > + offset = (entry & KVM_ITS_DTE_NEXT_MASK) >> KVM_ITS_DTE_NEXT_SHIFT; > + > + dev = vgic_its_alloc_device(its, id, itt_addr, num_eventid_bits); > + if (IS_ERR(dev)) > + return PTR_ERR(dev); > + > + ret = vgic_its_restore_itt(its, dev); > + if (ret) > + return ret; Shouldn't we free the device entry if the restore as failed? Thanks, M. -- Jazz is not dead, it just smell funny. From mboxrd@z Thu Jan 1 00:00:00 1970 From: marc.zyngier@arm.com (Marc Zyngier) Date: Sun, 07 May 2017 14:30:57 +0100 Subject: [PATCH v7 21/24] KVM: arm64: vgic-its: Device table save/restore In-Reply-To: <1494084283-12723-22-git-send-email-eric.auger@redhat.com> (Eric Auger's message of "Sat, 6 May 2017 17:24:40 +0200") References: <1494084283-12723-1-git-send-email-eric.auger@redhat.com> <1494084283-12723-22-git-send-email-eric.auger@redhat.com> Message-ID: <87zieoiyjy.fsf@on-the-bus.cambridge.arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Sat, May 06 2017 at 4:24:40 pm BST, Eric Auger wrote: > This patch saves the device table entries into guest RAM. > Both flat table and 2 stage tables are supported. DeviceId > indexing is used. > > For each device listed in the device table, we also save > the translation table using the vgic_its_save/restore_itt > routines. Those functions will be implemented in a subsequent > patch. > > On restore, devices are re-allocated and their itt are > re-built. > > Signed-off-by: Eric Auger > > --- > v5 -> v6: > - accomodate vgic_its_alloc_device change of proto > - define bit fields for L1 entries > - s/handle_l1_entry/handle_l1_dte > - s/ite_esz/dte_esz in handle_l1_dte > - check BASER valid bit > - s/nb_eventid_bits/num_eventid_bits > - new convention for returned values > - itt functions implemented in subsequent patch > > v4 -> v5: > - sort the device list by deviceid on device table save > - use defines for shifts and masks > - use abi->dte_esz > - clatify entry sizes for L1 and L2 tables > > v3 -> v4: > - use the new proto for its_alloc_device > - compute_next_devid_offset, vgic_its_flush/restore_itt > become static in this patch > - change in the DTE entry format with the introduction of the > valid bit and next field width decrease; ittaddr encoded > on its full range > - fix handle_l1_entry entry handling > - correct vgic_its_table_restore error handling > > v2 -> v3: > - fix itt_addr bitmask in vgic_its_restore_dte > - addition of return 0 in vgic_its_restore_ite moved to > the ITE related patch > > v1 -> v2: > - use 8 byte format for DTE and ITE > - support 2 stage format > - remove kvm parameter > - ITT flush/restore moved in a separate patch > - use deviceid indexing > --- > virt/kvm/arm/vgic/vgic-its.c | 194 +++++++++++++++++++++++++++++++++++++++++-- > virt/kvm/arm/vgic/vgic.h | 10 +++ > 2 files changed, 199 insertions(+), 5 deletions(-) > > diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c > index 90afc83..3dea626 100644 > --- a/virt/kvm/arm/vgic/vgic-its.c > +++ b/virt/kvm/arm/vgic/vgic-its.c > @@ -23,6 +23,7 @@ > #include > #include > #include > +#include > > #include > > @@ -1735,7 +1736,8 @@ int vgic_its_attr_regs_access(struct kvm_device *dev, > return ret; > } > > -u32 compute_next_devid_offset(struct list_head *h, struct its_device *dev) > +static u32 compute_next_devid_offset(struct list_head *h, > + struct its_device *dev) > { > struct its_device *next; > u32 next_offset; > @@ -1789,8 +1791,8 @@ typedef int (*entry_fn_t)(struct vgic_its *its, u32 id, void *entry, > * Return: < 0 on error, 0 if last element was identified, 1 otherwise > * (the last element may not be found on second level tables) > */ > -int scan_its_table(struct vgic_its *its, gpa_t base, int size, int esz, > - int start_id, entry_fn_t fn, void *opaque) > +static int scan_its_table(struct vgic_its *its, gpa_t base, int size, int esz, > + int start_id, entry_fn_t fn, void *opaque) > { > void *entry = kzalloc(esz, GFP_KERNEL); > struct kvm *kvm = its->dev->kvm; > @@ -1825,13 +1827,171 @@ int scan_its_table(struct vgic_its *its, gpa_t base, int size, int esz, > return ret; > } > > +static int vgic_its_save_itt(struct vgic_its *its, struct its_device *device) > +{ > + return -ENXIO; > +} > + > +static int vgic_its_restore_itt(struct vgic_its *its, struct its_device *dev) > +{ > + return -ENXIO; > +} > + > +/** > + * vgic_its_save_dte - Save a device table entry at a given GPA > + * > + * @its: ITS handle > + * @dev: ITS device > + * @ptr: GPA > + */ > +static int vgic_its_save_dte(struct vgic_its *its, struct its_device *dev, > + gpa_t ptr, int dte_esz) > +{ > + struct kvm *kvm = its->dev->kvm; > + u64 val, itt_addr_field; > + u32 next_offset; > + > + itt_addr_field = dev->itt_addr >> 8; > + next_offset = compute_next_devid_offset(&its->device_list, dev); > + val = (1ULL << KVM_ITS_DTE_VALID_SHIFT | > + ((u64)next_offset << KVM_ITS_DTE_NEXT_SHIFT) | > + (itt_addr_field << KVM_ITS_DTE_ITTADDR_SHIFT) | > + (dev->num_eventid_bits - 1)); > + val = cpu_to_le64(val); > + return kvm_write_guest(kvm, ptr, &val, dte_esz); > +} > + > +/** > + * vgic_its_restore_dte - restore a device table entry > + * > + * @its: its handle > + * @id: device id the DTE corresponds to > + * @ptr: kernel VA where the 8 byte DTE is located > + * @opaque: unused > + * > + * Return: < 0 on error, 0 if the dte is the last one, id offset to the > + * next dte otherwise > + */ > +static int vgic_its_restore_dte(struct vgic_its *its, u32 id, > + void *ptr, void *opaque) > +{ > + struct its_device *dev; > + gpa_t itt_addr; > + u8 num_eventid_bits; > + u64 entry = *(u64 *)ptr; > + bool valid; > + u32 offset; > + int ret; > + > + entry = le64_to_cpu(entry); > + > + valid = entry >> KVM_ITS_DTE_VALID_SHIFT; > + num_eventid_bits = (entry & KVM_ITS_DTE_SIZE_MASK) + 1; > + itt_addr = ((entry & KVM_ITS_DTE_ITTADDR_MASK) > + >> KVM_ITS_DTE_ITTADDR_SHIFT) << 8; > + > + if (!valid) > + return 1; > + > + /* dte entry is valid */ > + offset = (entry & KVM_ITS_DTE_NEXT_MASK) >> KVM_ITS_DTE_NEXT_SHIFT; > + > + dev = vgic_its_alloc_device(its, id, itt_addr, num_eventid_bits); > + if (IS_ERR(dev)) > + return PTR_ERR(dev); > + > + ret = vgic_its_restore_itt(its, dev); > + if (ret) > + return ret; Shouldn't we free the device entry if the restore as failed? Thanks, M. -- Jazz is not dead, it just smell funny.