| Message ID | 1488800074-21991-6-git-send-email-eric.auger@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Eric, On 06/03/17 11:34, Eric Auger wrote: > This patch implements vgic_its_has_attr_regs and vgic_its_attr_regs_access > upon the MMIO framework. VGIC ITS KVM device KVM_DEV_ARM_VGIC_GRP_ITS_REGS > group becomes functional. > > At least GITS_CREADR requires to differentiate a guest write action from a > user access. As such let's introduce a new uaccess_its_write > vgic_register_region callback. > > Signed-off-by: Eric Auger <eric.auger@redhat.com> > --- > virt/kvm/arm/vgic/vgic-its.c | 74 ++++++++++++++++++++++++++++++++++++------- > virt/kvm/arm/vgic/vgic-mmio.h | 9 ++++-- > 2 files changed, 69 insertions(+), 14 deletions(-) > > diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c > index 43bb17e..e9c8f9f 100644 > --- a/virt/kvm/arm/vgic/vgic-its.c > +++ b/virt/kvm/arm/vgic/vgic-its.c > @@ -1287,13 +1287,14 @@ static void vgic_mmio_write_its_baser(struct kvm *kvm, > *regptr = reg; > } > > -#define REGISTER_ITS_DESC(off, rd, wr, length, acc) \ > +#define REGISTER_ITS_DESC(off, rd, wr, uwr, length, acc) \ > { \ > .reg_offset = off, \ > .len = length, \ > .access_flags = acc, \ > .its_read = rd, \ > .its_write = wr, \ > + .uaccess_its_write = uwr, \ I was wondering if it would create less churn to keep this definition here (with .uaccess_its_write automatically becoming NULL), and then either open-code the one special case below or provide a second wrapper macro. But I guess either way is not really nice, so we could go with this approach here as well. > } > > static void its_mmio_write_wi(struct kvm *kvm, struct vgic_its *its, > @@ -1304,28 +1305,28 @@ static void its_mmio_write_wi(struct kvm *kvm, struct vgic_its *its, > > static struct vgic_register_region its_registers[] = { > REGISTER_ITS_DESC(GITS_CTLR, > - vgic_mmio_read_its_ctlr, vgic_mmio_write_its_ctlr, 4, > + vgic_mmio_read_its_ctlr, vgic_mmio_write_its_ctlr, NULL, 4, > VGIC_ACCESS_32bit), > REGISTER_ITS_DESC(GITS_IIDR, > - vgic_mmio_read_its_iidr, its_mmio_write_wi, 4, > + vgic_mmio_read_its_iidr, its_mmio_write_wi, NULL, 4, > VGIC_ACCESS_32bit), > REGISTER_ITS_DESC(GITS_TYPER, > - vgic_mmio_read_its_typer, its_mmio_write_wi, 8, > + vgic_mmio_read_its_typer, its_mmio_write_wi, NULL, 8, > VGIC_ACCESS_64bit | VGIC_ACCESS_32bit), > REGISTER_ITS_DESC(GITS_CBASER, > - vgic_mmio_read_its_cbaser, vgic_mmio_write_its_cbaser, 8, > + vgic_mmio_read_its_cbaser, vgic_mmio_write_its_cbaser, NULL, 8, > VGIC_ACCESS_64bit | VGIC_ACCESS_32bit), > REGISTER_ITS_DESC(GITS_CWRITER, > - vgic_mmio_read_its_cwriter, vgic_mmio_write_its_cwriter, 8, > - VGIC_ACCESS_64bit | VGIC_ACCESS_32bit), > + vgic_mmio_read_its_cwriter, vgic_mmio_write_its_cwriter, NULL, > + 8, VGIC_ACCESS_64bit | VGIC_ACCESS_32bit), > REGISTER_ITS_DESC(GITS_CREADR, > - vgic_mmio_read_its_creadr, its_mmio_write_wi, 8, > + vgic_mmio_read_its_creadr, its_mmio_write_wi, NULL, 8, > VGIC_ACCESS_64bit | VGIC_ACCESS_32bit), > REGISTER_ITS_DESC(GITS_BASER, > - vgic_mmio_read_its_baser, vgic_mmio_write_its_baser, 0x40, > + vgic_mmio_read_its_baser, vgic_mmio_write_its_baser, NULL, 0x40, > VGIC_ACCESS_64bit | VGIC_ACCESS_32bit), > REGISTER_ITS_DESC(GITS_IDREGS_BASE, > - vgic_mmio_read_its_idregs, its_mmio_write_wi, 0x30, > + vgic_mmio_read_its_idregs, its_mmio_write_wi, NULL, 0x30, > VGIC_ACCESS_32bit), > }; > > @@ -1448,14 +1449,63 @@ static void vgic_its_destroy(struct kvm_device *kvm_dev) > int vgic_its_has_attr_regs(struct kvm_device *dev, > struct kvm_device_attr *attr) > { > - return -ENXIO; > + const struct vgic_register_region *region; > + struct vgic_io_device iodev = { > + .regions = its_registers, > + .nr_regions = ARRAY_SIZE(its_registers), > + }; > + gpa_t offset; > + > + offset = attr->attr; Those two can be on one line. But actually why not just put attr->attr below and save that variable at all? > + > + region = vgic_find_mmio_region(iodev.regions, > + iodev.nr_regions, > + offset); > + if (!region) > + return -ENXIO; Nit: empty line here? > + return 0; > } > > int vgic_its_attr_regs_access(struct kvm_device *dev, > struct kvm_device_attr *attr, > u64 *reg, bool is_write) > { > - return -ENXIO; > + const struct vgic_register_region *region; > + struct vgic_io_device iodev = { > + .regions = its_registers, > + .nr_regions = ARRAY_SIZE(its_registers), > + }; > + struct vgic_its *its = dev->private; > + gpa_t addr, offset; > + unsigned int len; > + > + if (IS_VGIC_ADDR_UNDEF(its->vgic_its_base)) > + return -ENXIO; > + > + offset = attr->attr; > + if (offset & 0x7) > + return -EINVAL; Isn't this still breaking IIDR reads (a 32-bit register at offset 0x4)? > + > + addr = its->vgic_its_base + offset; > + > + region = vgic_find_mmio_region(iodev.regions, > + iodev.nr_regions, > + offset); > + if (!region) > + return -ENXIO; > + > + len = region->access_flags & VGIC_ACCESS_64bit ? 8 : 4; Can you add a comment that states that we only support full register accesses via this interface (deviating from the spec which allows split accesses to 64-bit registers)? I think that's mentioned somewhere else (Documentation/...), but it avoids confusion for the casual reader here. Also I am wondering if that way of using the pointer here for both 32- and 64-bit registers breaks on big endian? Or is it specified somewhere that this interface uses LE only? The rest looks fine, thanks! Cheers, Andre. > + if (is_write) { > + if (region->uaccess_its_write) > + region->uaccess_its_write(dev->kvm, its, addr, > + len, *reg); > + else > + region->its_write(dev->kvm, its, addr, len, *reg); > + } else { > + *reg = region->its_read(dev->kvm, its, addr, len); > + } > + return 0; > } > > static int vgic_its_has_attr(struct kvm_device *dev, > diff --git a/virt/kvm/arm/vgic/vgic-mmio.h b/virt/kvm/arm/vgic/vgic-mmio.h > index 055ad42..ad8a585 100644 > --- a/virt/kvm/arm/vgic/vgic-mmio.h > +++ b/virt/kvm/arm/vgic/vgic-mmio.h > @@ -36,8 +36,13 @@ struct vgic_register_region { > }; > unsigned long (*uaccess_read)(struct kvm_vcpu *vcpu, gpa_t addr, > unsigned int len); > - void (*uaccess_write)(struct kvm_vcpu *vcpu, gpa_t addr, > - unsigned int len, unsigned long val); > + union { > + void (*uaccess_write)(struct kvm_vcpu *vcpu, gpa_t addr, > + unsigned int len, unsigned long val); > + void (*uaccess_its_write)(struct kvm *kvm, struct vgic_its *its, > + gpa_t addr, unsigned int len, > + unsigned long val); > + }; > }; > > extern struct kvm_io_device_ops kvm_io_gic_ops; >
Andre, On 20/03/2017 19:13, Andre Przywara wrote: > Hi Eric, > > On 06/03/17 11:34, Eric Auger wrote: >> This patch implements vgic_its_has_attr_regs and vgic_its_attr_regs_access >> upon the MMIO framework. VGIC ITS KVM device KVM_DEV_ARM_VGIC_GRP_ITS_REGS >> group becomes functional. >> >> At least GITS_CREADR requires to differentiate a guest write action from a >> user access. As such let's introduce a new uaccess_its_write >> vgic_register_region callback. >> >> Signed-off-by: Eric Auger <eric.auger@redhat.com> >> --- >> virt/kvm/arm/vgic/vgic-its.c | 74 ++++++++++++++++++++++++++++++++++++------- >> virt/kvm/arm/vgic/vgic-mmio.h | 9 ++++-- >> 2 files changed, 69 insertions(+), 14 deletions(-) >> >> diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c >> index 43bb17e..e9c8f9f 100644 >> --- a/virt/kvm/arm/vgic/vgic-its.c >> +++ b/virt/kvm/arm/vgic/vgic-its.c >> @@ -1287,13 +1287,14 @@ static void vgic_mmio_write_its_baser(struct kvm *kvm, >> *regptr = reg; >> } >> >> -#define REGISTER_ITS_DESC(off, rd, wr, length, acc) \ >> +#define REGISTER_ITS_DESC(off, rd, wr, uwr, length, acc) \ >> { \ >> .reg_offset = off, \ >> .len = length, \ >> .access_flags = acc, \ >> .its_read = rd, \ >> .its_write = wr, \ >> + .uaccess_its_write = uwr, \ > > I was wondering if it would create less churn to keep this definition > here (with .uaccess_its_write automatically becoming NULL), and then > either open-code the one special case below or provide a second wrapper > macro. But I guess either way is not really nice, so we could go with > this approach here as well. Agreed. I plan to introduce REGISTER_ITS_DESC_UACCESS in next patch instead. > >> } >> >> static void its_mmio_write_wi(struct kvm *kvm, struct vgic_its *its, >> @@ -1304,28 +1305,28 @@ static void its_mmio_write_wi(struct kvm *kvm, struct vgic_its *its, >> >> static struct vgic_register_region its_registers[] = { >> REGISTER_ITS_DESC(GITS_CTLR, >> - vgic_mmio_read_its_ctlr, vgic_mmio_write_its_ctlr, 4, >> + vgic_mmio_read_its_ctlr, vgic_mmio_write_its_ctlr, NULL, 4, >> VGIC_ACCESS_32bit), >> REGISTER_ITS_DESC(GITS_IIDR, >> - vgic_mmio_read_its_iidr, its_mmio_write_wi, 4, >> + vgic_mmio_read_its_iidr, its_mmio_write_wi, NULL, 4, >> VGIC_ACCESS_32bit), >> REGISTER_ITS_DESC(GITS_TYPER, >> - vgic_mmio_read_its_typer, its_mmio_write_wi, 8, >> + vgic_mmio_read_its_typer, its_mmio_write_wi, NULL, 8, >> VGIC_ACCESS_64bit | VGIC_ACCESS_32bit), >> REGISTER_ITS_DESC(GITS_CBASER, >> - vgic_mmio_read_its_cbaser, vgic_mmio_write_its_cbaser, 8, >> + vgic_mmio_read_its_cbaser, vgic_mmio_write_its_cbaser, NULL, 8, >> VGIC_ACCESS_64bit | VGIC_ACCESS_32bit), >> REGISTER_ITS_DESC(GITS_CWRITER, >> - vgic_mmio_read_its_cwriter, vgic_mmio_write_its_cwriter, 8, >> - VGIC_ACCESS_64bit | VGIC_ACCESS_32bit), >> + vgic_mmio_read_its_cwriter, vgic_mmio_write_its_cwriter, NULL, >> + 8, VGIC_ACCESS_64bit | VGIC_ACCESS_32bit), >> REGISTER_ITS_DESC(GITS_CREADR, >> - vgic_mmio_read_its_creadr, its_mmio_write_wi, 8, >> + vgic_mmio_read_its_creadr, its_mmio_write_wi, NULL, 8, >> VGIC_ACCESS_64bit | VGIC_ACCESS_32bit), >> REGISTER_ITS_DESC(GITS_BASER, >> - vgic_mmio_read_its_baser, vgic_mmio_write_its_baser, 0x40, >> + vgic_mmio_read_its_baser, vgic_mmio_write_its_baser, NULL, 0x40, >> VGIC_ACCESS_64bit | VGIC_ACCESS_32bit), >> REGISTER_ITS_DESC(GITS_IDREGS_BASE, >> - vgic_mmio_read_its_idregs, its_mmio_write_wi, 0x30, >> + vgic_mmio_read_its_idregs, its_mmio_write_wi, NULL, 0x30, >> VGIC_ACCESS_32bit), >> }; >> >> @@ -1448,14 +1449,63 @@ static void vgic_its_destroy(struct kvm_device *kvm_dev) >> int vgic_its_has_attr_regs(struct kvm_device *dev, >> struct kvm_device_attr *attr) >> { >> - return -ENXIO; >> + const struct vgic_register_region *region; >> + struct vgic_io_device iodev = { >> + .regions = its_registers, >> + .nr_regions = ARRAY_SIZE(its_registers), >> + }; >> + gpa_t offset; >> + >> + offset = attr->attr; > > Those two can be on one line. > But actually why not just put attr->attr below and save that variable at > all? done > >> + >> + region = vgic_find_mmio_region(iodev.regions, >> + iodev.nr_regions, >> + offset); >> + if (!region) >> + return -ENXIO; > > Nit: empty line here? done > >> + return 0; >> } >> >> int vgic_its_attr_regs_access(struct kvm_device *dev, >> struct kvm_device_attr *attr, >> u64 *reg, bool is_write) >> { >> - return -ENXIO; >> + const struct vgic_register_region *region; >> + struct vgic_io_device iodev = { >> + .regions = its_registers, >> + .nr_regions = ARRAY_SIZE(its_registers), >> + }; >> + struct vgic_its *its = dev->private; >> + gpa_t addr, offset; >> + unsigned int len; >> + >> + if (IS_VGIC_ADDR_UNDEF(its->vgic_its_base)) >> + return -ENXIO; >> + >> + offset = attr->attr; >> + if (offset & 0x7) >> + return -EINVAL; > > Isn't this still breaking IIDR reads (a 32-bit register at offset 0x4)? Hum yes it does. I will fix & test that. At the moment I was not saving/restoring the IIDR but this is the plan now. Thanks for spotting this. > >> + >> + addr = its->vgic_its_base + offset; >> + >> + region = vgic_find_mmio_region(iodev.regions, >> + iodev.nr_regions, >> + offset); >> + if (!region) >> + return -ENXIO; >> + >> + len = region->access_flags & VGIC_ACCESS_64bit ? 8 : 4; > > Can you add a comment that states that we only support full register > accesses via this interface (deviating from the spec which allows split > accesses to 64-bit registers)? I think that's mentioned somewhere else > (Documentation/...), but it avoids confusion for the casual reader here. Added that comment. > > Also I am wondering if that way of using the pointer here for both 32- > and 64-bit registers breaks on big endian? Or is it specified somewhere > that this interface uses LE only? Agreed, I used add vgic_data_mmio_bus_to_host and vgic_data_host_to_mmio_bus handling. Thanks Eric > > The rest looks fine, thanks! > > Cheers, > Andre. > >> + if (is_write) { >> + if (region->uaccess_its_write) >> + region->uaccess_its_write(dev->kvm, its, addr, >> + len, *reg); >> + else >> + region->its_write(dev->kvm, its, addr, len, *reg); >> + } else { >> + *reg = region->its_read(dev->kvm, its, addr, len); >> + } >> + return 0; >> } >> >> static int vgic_its_has_attr(struct kvm_device *dev, >> diff --git a/virt/kvm/arm/vgic/vgic-mmio.h b/virt/kvm/arm/vgic/vgic-mmio.h >> index 055ad42..ad8a585 100644 >> --- a/virt/kvm/arm/vgic/vgic-mmio.h >> +++ b/virt/kvm/arm/vgic/vgic-mmio.h >> @@ -36,8 +36,13 @@ struct vgic_register_region { >> }; >> unsigned long (*uaccess_read)(struct kvm_vcpu *vcpu, gpa_t addr, >> unsigned int len); >> - void (*uaccess_write)(struct kvm_vcpu *vcpu, gpa_t addr, >> - unsigned int len, unsigned long val); >> + union { >> + void (*uaccess_write)(struct kvm_vcpu *vcpu, gpa_t addr, >> + unsigned int len, unsigned long val); >> + void (*uaccess_its_write)(struct kvm *kvm, struct vgic_its *its, >> + gpa_t addr, unsigned int len, >> + unsigned long val); >> + }; >> }; >> >> extern struct kvm_io_device_ops kvm_io_gic_ops; >> > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel >
diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c index 43bb17e..e9c8f9f 100644 --- a/virt/kvm/arm/vgic/vgic-its.c +++ b/virt/kvm/arm/vgic/vgic-its.c @@ -1287,13 +1287,14 @@ static void vgic_mmio_write_its_baser(struct kvm *kvm, *regptr = reg; } -#define REGISTER_ITS_DESC(off, rd, wr, length, acc) \ +#define REGISTER_ITS_DESC(off, rd, wr, uwr, length, acc) \ { \ .reg_offset = off, \ .len = length, \ .access_flags = acc, \ .its_read = rd, \ .its_write = wr, \ + .uaccess_its_write = uwr, \ } static void its_mmio_write_wi(struct kvm *kvm, struct vgic_its *its, @@ -1304,28 +1305,28 @@ static void its_mmio_write_wi(struct kvm *kvm, struct vgic_its *its, static struct vgic_register_region its_registers[] = { REGISTER_ITS_DESC(GITS_CTLR, - vgic_mmio_read_its_ctlr, vgic_mmio_write_its_ctlr, 4, + vgic_mmio_read_its_ctlr, vgic_mmio_write_its_ctlr, NULL, 4, VGIC_ACCESS_32bit), REGISTER_ITS_DESC(GITS_IIDR, - vgic_mmio_read_its_iidr, its_mmio_write_wi, 4, + vgic_mmio_read_its_iidr, its_mmio_write_wi, NULL, 4, VGIC_ACCESS_32bit), REGISTER_ITS_DESC(GITS_TYPER, - vgic_mmio_read_its_typer, its_mmio_write_wi, 8, + vgic_mmio_read_its_typer, its_mmio_write_wi, NULL, 8, VGIC_ACCESS_64bit | VGIC_ACCESS_32bit), REGISTER_ITS_DESC(GITS_CBASER, - vgic_mmio_read_its_cbaser, vgic_mmio_write_its_cbaser, 8, + vgic_mmio_read_its_cbaser, vgic_mmio_write_its_cbaser, NULL, 8, VGIC_ACCESS_64bit | VGIC_ACCESS_32bit), REGISTER_ITS_DESC(GITS_CWRITER, - vgic_mmio_read_its_cwriter, vgic_mmio_write_its_cwriter, 8, - VGIC_ACCESS_64bit | VGIC_ACCESS_32bit), + vgic_mmio_read_its_cwriter, vgic_mmio_write_its_cwriter, NULL, + 8, VGIC_ACCESS_64bit | VGIC_ACCESS_32bit), REGISTER_ITS_DESC(GITS_CREADR, - vgic_mmio_read_its_creadr, its_mmio_write_wi, 8, + vgic_mmio_read_its_creadr, its_mmio_write_wi, NULL, 8, VGIC_ACCESS_64bit | VGIC_ACCESS_32bit), REGISTER_ITS_DESC(GITS_BASER, - vgic_mmio_read_its_baser, vgic_mmio_write_its_baser, 0x40, + vgic_mmio_read_its_baser, vgic_mmio_write_its_baser, NULL, 0x40, VGIC_ACCESS_64bit | VGIC_ACCESS_32bit), REGISTER_ITS_DESC(GITS_IDREGS_BASE, - vgic_mmio_read_its_idregs, its_mmio_write_wi, 0x30, + vgic_mmio_read_its_idregs, its_mmio_write_wi, NULL, 0x30, VGIC_ACCESS_32bit), }; @@ -1448,14 +1449,63 @@ static void vgic_its_destroy(struct kvm_device *kvm_dev) int vgic_its_has_attr_regs(struct kvm_device *dev, struct kvm_device_attr *attr) { - return -ENXIO; + const struct vgic_register_region *region; + struct vgic_io_device iodev = { + .regions = its_registers, + .nr_regions = ARRAY_SIZE(its_registers), + }; + gpa_t offset; + + offset = attr->attr; + + region = vgic_find_mmio_region(iodev.regions, + iodev.nr_regions, + offset); + if (!region) + return -ENXIO; + return 0; } int vgic_its_attr_regs_access(struct kvm_device *dev, struct kvm_device_attr *attr, u64 *reg, bool is_write) { - return -ENXIO; + const struct vgic_register_region *region; + struct vgic_io_device iodev = { + .regions = its_registers, + .nr_regions = ARRAY_SIZE(its_registers), + }; + struct vgic_its *its = dev->private; + gpa_t addr, offset; + unsigned int len; + + if (IS_VGIC_ADDR_UNDEF(its->vgic_its_base)) + return -ENXIO; + + offset = attr->attr; + if (offset & 0x7) + return -EINVAL; + + addr = its->vgic_its_base + offset; + + region = vgic_find_mmio_region(iodev.regions, + iodev.nr_regions, + offset); + if (!region) + return -ENXIO; + + len = region->access_flags & VGIC_ACCESS_64bit ? 8 : 4; + + if (is_write) { + if (region->uaccess_its_write) + region->uaccess_its_write(dev->kvm, its, addr, + len, *reg); + else + region->its_write(dev->kvm, its, addr, len, *reg); + } else { + *reg = region->its_read(dev->kvm, its, addr, len); + } + return 0; } static int vgic_its_has_attr(struct kvm_device *dev, diff --git a/virt/kvm/arm/vgic/vgic-mmio.h b/virt/kvm/arm/vgic/vgic-mmio.h index 055ad42..ad8a585 100644 --- a/virt/kvm/arm/vgic/vgic-mmio.h +++ b/virt/kvm/arm/vgic/vgic-mmio.h @@ -36,8 +36,13 @@ struct vgic_register_region { }; unsigned long (*uaccess_read)(struct kvm_vcpu *vcpu, gpa_t addr, unsigned int len); - void (*uaccess_write)(struct kvm_vcpu *vcpu, gpa_t addr, - unsigned int len, unsigned long val); + union { + void (*uaccess_write)(struct kvm_vcpu *vcpu, gpa_t addr, + unsigned int len, unsigned long val); + void (*uaccess_its_write)(struct kvm *kvm, struct vgic_its *its, + gpa_t addr, unsigned int len, + unsigned long val); + }; }; extern struct kvm_io_device_ops kvm_io_gic_ops;
This patch implements vgic_its_has_attr_regs and vgic_its_attr_regs_access upon the MMIO framework. VGIC ITS KVM device KVM_DEV_ARM_VGIC_GRP_ITS_REGS group becomes functional. At least GITS_CREADR requires to differentiate a guest write action from a user access. As such let's introduce a new uaccess_its_write vgic_register_region callback. Signed-off-by: Eric Auger <eric.auger@redhat.com> --- virt/kvm/arm/vgic/vgic-its.c | 74 ++++++++++++++++++++++++++++++++++++------- virt/kvm/arm/vgic/vgic-mmio.h | 9 ++++-- 2 files changed, 69 insertions(+), 14 deletions(-)