| Message ID | 20210820155918.7518-15-brijesh.singh@amd.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Add AMD Secure Nested Paging (SEV-SNP) Hypervisor Support | expand |
On Fri, Aug 20, 2021 at 9:00 AM Brijesh Singh <brijesh.singh@amd.com> wrote: > > The behavior and requirement for the SEV-legacy command is altered when > the SNP firmware is in the INIT state. See SEV-SNP firmware specification > for more details. > > Allocate the Trusted Memory Region (TMR) as a 2mb sized/aligned region > when SNP is enabled to satify new requirements for the SNP. Continue > allocating a 1mb region for !SNP configuration. > > While at it, provide API that can be used by others to allocate a page > that can be used by the firmware. The immediate user for this API will > be the KVM driver. The KVM driver to need to allocate a firmware context > page during the guest creation. The context page need to be updated > by the firmware. See the SEV-SNP specification for further details. > > Signed-off-by: Brijesh Singh <brijesh.singh@amd.com> > --- > drivers/crypto/ccp/sev-dev.c | 169 ++++++++++++++++++++++++++++++++++- > include/linux/psp-sev.h | 11 +++ > 2 files changed, 176 insertions(+), 4 deletions(-) > > diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c > index 01edad9116f2..34dc358b13b9 100644 > --- a/drivers/crypto/ccp/sev-dev.c > +++ b/drivers/crypto/ccp/sev-dev.c > @@ -62,6 +62,14 @@ static int psp_timeout; > #define SEV_ES_TMR_SIZE (1024 * 1024) > static void *sev_es_tmr; > > +/* When SEV-SNP is enabled the TMR needs to be 2MB aligned and 2MB size. */ > +#define SEV_SNP_ES_TMR_SIZE (2 * 1024 * 1024) > + > +static size_t sev_es_tmr_size = SEV_ES_TMR_SIZE; > + > +static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret); > +static int sev_do_cmd(int cmd, void *data, int *psp_ret); > + > static inline bool sev_version_greater_or_equal(u8 maj, u8 min) > { > struct sev_device *sev = psp_master->sev_data; > @@ -159,6 +167,156 @@ static int sev_cmd_buffer_len(int cmd) > return 0; > } > > +static void snp_leak_pages(unsigned long pfn, unsigned int npages) > +{ > + WARN(1, "psc failed, pfn 0x%lx pages %d (leaking)\n", pfn, npages); > + while (npages--) { > + memory_failure(pfn, 0); > + dump_rmpentry(pfn); > + pfn++; > + } > +} > + > +static int snp_reclaim_pages(unsigned long pfn, unsigned int npages, bool locked) > +{ > + struct sev_data_snp_page_reclaim data; > + int ret, err, i, n = 0; > + > + for (i = 0; i < npages; i++) { > + memset(&data, 0, sizeof(data)); > + data.paddr = pfn << PAGE_SHIFT; > + > + if (locked) > + ret = __sev_do_cmd_locked(SEV_CMD_SNP_PAGE_RECLAIM, &data, &err); > + else > + ret = sev_do_cmd(SEV_CMD_SNP_PAGE_RECLAIM, &data, &err); > + if (ret) > + goto cleanup; > + > + ret = rmp_make_shared(pfn, PG_LEVEL_4K); > + if (ret) > + goto cleanup; > + > + pfn++; > + n++; > + } > + > + return 0; > + > +cleanup: > + /* > + * If failed to reclaim the page then page is no longer safe to > + * be released, leak it. > + */ > + snp_leak_pages(pfn, npages - n); > + return ret; > +} > + > +static inline int rmp_make_firmware(unsigned long pfn, int level) > +{ > + return rmp_make_private(pfn, 0, level, 0, true); > +} > + > +static int snp_set_rmp_state(unsigned long paddr, unsigned int npages, bool to_fw, bool locked, > + bool need_reclaim) > +{ > + unsigned long pfn = __sme_clr(paddr) >> PAGE_SHIFT; /* Cbit maybe set in the paddr */ > + int rc, n = 0, i; > + > + for (i = 0; i < npages; i++) { > + if (to_fw) > + rc = rmp_make_firmware(pfn, PG_LEVEL_4K); > + else > + rc = need_reclaim ? snp_reclaim_pages(pfn, 1, locked) : > + rmp_make_shared(pfn, PG_LEVEL_4K); > + if (rc) > + goto cleanup; > + > + pfn++; > + n++; > + } > + > + return 0; > + > +cleanup: > + /* Try unrolling the firmware state changes */ > + if (to_fw) { > + /* > + * Reclaim the pages which were already changed to the > + * firmware state. > + */ > + snp_reclaim_pages(paddr >> PAGE_SHIFT, n, locked); > + > + return rc; > + } > + > + /* > + * If failed to change the page state to shared, then its not safe > + * to release the page back to the system, leak it. > + */ > + snp_leak_pages(pfn, npages - n); > + > + return rc; > +} > + > +static struct page *__snp_alloc_firmware_pages(gfp_t gfp_mask, int order, bool locked) > +{ > + unsigned long npages = 1ul << order, paddr; > + struct sev_device *sev; > + struct page *page; > + > + if (!psp_master || !psp_master->sev_data) > + return ERR_PTR(-EINVAL); > + > + page = alloc_pages(gfp_mask, order); > + if (!page) > + return NULL; > + > + /* If SEV-SNP is initialized then add the page in RMP table. */ > + sev = psp_master->sev_data; > + if (!sev->snp_inited) > + return page; > + > + paddr = __pa((unsigned long)page_address(page)); > + if (snp_set_rmp_state(paddr, npages, true, locked, false)) > + return NULL; > + > + return page; > +} > + > +void *snp_alloc_firmware_page(gfp_t gfp_mask) > +{ > + struct page *page; > + > + page = __snp_alloc_firmware_pages(gfp_mask, 0, false); > + > + return page ? page_address(page) : NULL; > +} > +EXPORT_SYMBOL_GPL(snp_alloc_firmware_page); > + > +static void __snp_free_firmware_pages(struct page *page, int order, bool locked) > +{ > + unsigned long paddr, npages = 1ul << order; > + > + if (!page) > + return; > + > + paddr = __pa((unsigned long)page_address(page)); > + if (snp_set_rmp_state(paddr, npages, false, locked, true)) > + return; > + > + __free_pages(page, order); > +} > + > +void snp_free_firmware_page(void *addr) > +{ > + if (!addr) > + return; > + > + __snp_free_firmware_pages(virt_to_page(addr), 0, false); > +} > +EXPORT_SYMBOL(snp_free_firmware_page); > + > static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret) > { > struct psp_device *psp = psp_master; > @@ -281,7 +439,7 @@ static int __sev_platform_init_locked(int *error) > > data.flags |= SEV_INIT_FLAGS_SEV_ES; > data.tmr_address = tmr_pa; > - data.tmr_len = SEV_ES_TMR_SIZE; > + data.tmr_len = sev_es_tmr_size; > } > > rc = __sev_do_cmd_locked(SEV_CMD_INIT, &data, error); > @@ -638,6 +796,8 @@ static int __sev_snp_init_locked(int *error) > sev->snp_inited = true; > dev_dbg(sev->dev, "SEV-SNP firmware initialized\n"); > > + sev_es_tmr_size = SEV_SNP_ES_TMR_SIZE; > + > return rc; > } > > @@ -1161,8 +1321,9 @@ static void sev_firmware_shutdown(struct sev_device *sev) > /* The TMR area was encrypted, flush it from the cache */ > wbinvd_on_all_cpus(); > > - free_pages((unsigned long)sev_es_tmr, > - get_order(SEV_ES_TMR_SIZE)); > + __snp_free_firmware_pages(virt_to_page(sev_es_tmr), > + get_order(sev_es_tmr_size), > + false); Shouldn't there be a check here for snp_inited before calling rmpupdate. TMR page can exist even if the SNP is not supported. > sev_es_tmr = NULL; > } > > @@ -1233,7 +1394,7 @@ void sev_pci_init(void) > } > > /* Obtain the TMR memory area for SEV-ES use */ > - tmr_page = alloc_pages(GFP_KERNEL, get_order(SEV_ES_TMR_SIZE)); > + tmr_page = __snp_alloc_firmware_pages(GFP_KERNEL, get_order(sev_es_tmr_size), false); > if (tmr_page) { > sev_es_tmr = page_address(tmr_page); > } else { > diff --git a/include/linux/psp-sev.h b/include/linux/psp-sev.h > index f2105a8755f9..00bd684dc094 100644 > --- a/include/linux/psp-sev.h > +++ b/include/linux/psp-sev.h > @@ -12,6 +12,8 @@ > #ifndef __PSP_SEV_H__ > #define __PSP_SEV_H__ > > +#include <linux/sev.h> > + > #include <uapi/linux/psp-sev.h> > > #ifdef CONFIG_X86 > @@ -919,6 +921,8 @@ int snp_guest_page_reclaim(struct sev_data_snp_page_reclaim *data, int *error); > int snp_guest_dbg_decrypt(struct sev_data_snp_dbg *data, int *error); > > void *psp_copy_user_blob(u64 uaddr, u32 len); > +void *snp_alloc_firmware_page(gfp_t mask); > +void snp_free_firmware_page(void *addr); > > #else /* !CONFIG_CRYPTO_DEV_SP_PSP */ > > @@ -960,6 +964,13 @@ static inline int snp_guest_dbg_decrypt(struct sev_data_snp_dbg *data, int *erro > return -ENODEV; > } > > +static inline void *snp_alloc_firmware_page(gfp_t mask) > +{ > + return NULL; > +} > + > +static inline void snp_free_firmware_page(void *addr) { } > + > #endif /* CONFIG_CRYPTO_DEV_SP_PSP */ > > #endif /* __PSP_SEV_H__ */ > -- > 2.17.1 > >
Hi Alper, On 2/25/22 12:03, Alper Gun wrote: >> >> - free_pages((unsigned long)sev_es_tmr, >> - get_order(SEV_ES_TMR_SIZE)); >> + __snp_free_firmware_pages(virt_to_page(sev_es_tmr), >> + get_order(sev_es_tmr_size), >> + false); > Shouldn't there be a check here for snp_inited before calling rmpupdate. > TMR page can exist even if the SNP is not supported. > Yes, I have this fix in my WIP branch and will be included in the v6. thanks
Similar to the TMR page, sev_init_ex_buffer should be owned by firmware. Otherwise INIT_EX won't work with the SNP. Since v5 patches are prepared before INIT_EX work, I wanted to bring this to your attention. One difference from the TMR page, sev_init_ex_buffer has to be in the direct map. Firmware pages are removed from directmap in v5 patches. But the kernel reads sev_init_ex_buffer later to write into a persistent file. I have a version to make it work, if you're interested I can share. On Fri, Aug 20, 2021 at 9:00 AM Brijesh Singh <brijesh.singh@amd.com> wrote: > > The behavior and requirement for the SEV-legacy command is altered when > the SNP firmware is in the INIT state. See SEV-SNP firmware specification > for more details. > > Allocate the Trusted Memory Region (TMR) as a 2mb sized/aligned region > when SNP is enabled to satify new requirements for the SNP. Continue > allocating a 1mb region for !SNP configuration. > > While at it, provide API that can be used by others to allocate a page > that can be used by the firmware. The immediate user for this API will > be the KVM driver. The KVM driver to need to allocate a firmware context > page during the guest creation. The context page need to be updated > by the firmware. See the SEV-SNP specification for further details. > > Signed-off-by: Brijesh Singh <brijesh.singh@amd.com> > --- > drivers/crypto/ccp/sev-dev.c | 169 ++++++++++++++++++++++++++++++++++- > include/linux/psp-sev.h | 11 +++ > 2 files changed, 176 insertions(+), 4 deletions(-) > > diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c > index 01edad9116f2..34dc358b13b9 100644 > --- a/drivers/crypto/ccp/sev-dev.c > +++ b/drivers/crypto/ccp/sev-dev.c > @@ -62,6 +62,14 @@ static int psp_timeout; > #define SEV_ES_TMR_SIZE (1024 * 1024) > static void *sev_es_tmr; > > +/* When SEV-SNP is enabled the TMR needs to be 2MB aligned and 2MB size. */ > +#define SEV_SNP_ES_TMR_SIZE (2 * 1024 * 1024) > + > +static size_t sev_es_tmr_size = SEV_ES_TMR_SIZE; > + > +static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret); > +static int sev_do_cmd(int cmd, void *data, int *psp_ret); > + > static inline bool sev_version_greater_or_equal(u8 maj, u8 min) > { > struct sev_device *sev = psp_master->sev_data; > @@ -159,6 +167,156 @@ static int sev_cmd_buffer_len(int cmd) > return 0; > } > > +static void snp_leak_pages(unsigned long pfn, unsigned int npages) > +{ > + WARN(1, "psc failed, pfn 0x%lx pages %d (leaking)\n", pfn, npages); > + while (npages--) { > + memory_failure(pfn, 0); > + dump_rmpentry(pfn); > + pfn++; > + } > +} > + > +static int snp_reclaim_pages(unsigned long pfn, unsigned int npages, bool locked) > +{ > + struct sev_data_snp_page_reclaim data; > + int ret, err, i, n = 0; > + > + for (i = 0; i < npages; i++) { > + memset(&data, 0, sizeof(data)); > + data.paddr = pfn << PAGE_SHIFT; > + > + if (locked) > + ret = __sev_do_cmd_locked(SEV_CMD_SNP_PAGE_RECLAIM, &data, &err); > + else > + ret = sev_do_cmd(SEV_CMD_SNP_PAGE_RECLAIM, &data, &err); > + if (ret) > + goto cleanup; > + > + ret = rmp_make_shared(pfn, PG_LEVEL_4K); > + if (ret) > + goto cleanup; > + > + pfn++; > + n++; > + } > + > + return 0; > + > +cleanup: > + /* > + * If failed to reclaim the page then page is no longer safe to > + * be released, leak it. > + */ > + snp_leak_pages(pfn, npages - n); > + return ret; > +} > + > +static inline int rmp_make_firmware(unsigned long pfn, int level) > +{ > + return rmp_make_private(pfn, 0, level, 0, true); > +} > + > +static int snp_set_rmp_state(unsigned long paddr, unsigned int npages, bool to_fw, bool locked, > + bool need_reclaim) > +{ > + unsigned long pfn = __sme_clr(paddr) >> PAGE_SHIFT; /* Cbit maybe set in the paddr */ > + int rc, n = 0, i; > + > + for (i = 0; i < npages; i++) { > + if (to_fw) > + rc = rmp_make_firmware(pfn, PG_LEVEL_4K); > + else > + rc = need_reclaim ? snp_reclaim_pages(pfn, 1, locked) : > + rmp_make_shared(pfn, PG_LEVEL_4K); > + if (rc) > + goto cleanup; > + > + pfn++; > + n++; > + } > + > + return 0; > + > +cleanup: > + /* Try unrolling the firmware state changes */ > + if (to_fw) { > + /* > + * Reclaim the pages which were already changed to the > + * firmware state. > + */ > + snp_reclaim_pages(paddr >> PAGE_SHIFT, n, locked); > + > + return rc; > + } > + > + /* > + * If failed to change the page state to shared, then its not safe > + * to release the page back to the system, leak it. > + */ > + snp_leak_pages(pfn, npages - n); > + > + return rc; > +} > + > +static struct page *__snp_alloc_firmware_pages(gfp_t gfp_mask, int order, bool locked) > +{ > + unsigned long npages = 1ul << order, paddr; > + struct sev_device *sev; > + struct page *page; > + > + if (!psp_master || !psp_master->sev_data) > + return ERR_PTR(-EINVAL); > + > + page = alloc_pages(gfp_mask, order); > + if (!page) > + return NULL; > + > + /* If SEV-SNP is initialized then add the page in RMP table. */ > + sev = psp_master->sev_data; > + if (!sev->snp_inited) > + return page; > + > + paddr = __pa((unsigned long)page_address(page)); > + if (snp_set_rmp_state(paddr, npages, true, locked, false)) > + return NULL; > + > + return page; > +} > + > +void *snp_alloc_firmware_page(gfp_t gfp_mask) > +{ > + struct page *page; > + > + page = __snp_alloc_firmware_pages(gfp_mask, 0, false); > + > + return page ? page_address(page) : NULL; > +} > +EXPORT_SYMBOL_GPL(snp_alloc_firmware_page); > + > +static void __snp_free_firmware_pages(struct page *page, int order, bool locked) > +{ > + unsigned long paddr, npages = 1ul << order; > + > + if (!page) > + return; > + > + paddr = __pa((unsigned long)page_address(page)); > + if (snp_set_rmp_state(paddr, npages, false, locked, true)) > + return; > + > + __free_pages(page, order); > +} > + > +void snp_free_firmware_page(void *addr) > +{ > + if (!addr) > + return; > + > + __snp_free_firmware_pages(virt_to_page(addr), 0, false); > +} > +EXPORT_SYMBOL(snp_free_firmware_page); > + > static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret) > { > struct psp_device *psp = psp_master; > @@ -281,7 +439,7 @@ static int __sev_platform_init_locked(int *error) > > data.flags |= SEV_INIT_FLAGS_SEV_ES; > data.tmr_address = tmr_pa; > - data.tmr_len = SEV_ES_TMR_SIZE; > + data.tmr_len = sev_es_tmr_size; > } > > rc = __sev_do_cmd_locked(SEV_CMD_INIT, &data, error); > @@ -638,6 +796,8 @@ static int __sev_snp_init_locked(int *error) > sev->snp_inited = true; > dev_dbg(sev->dev, "SEV-SNP firmware initialized\n"); > > + sev_es_tmr_size = SEV_SNP_ES_TMR_SIZE; > + > return rc; > } > > @@ -1161,8 +1321,9 @@ static void sev_firmware_shutdown(struct sev_device *sev) > /* The TMR area was encrypted, flush it from the cache */ > wbinvd_on_all_cpus(); > > - free_pages((unsigned long)sev_es_tmr, > - get_order(SEV_ES_TMR_SIZE)); > + __snp_free_firmware_pages(virt_to_page(sev_es_tmr), > + get_order(sev_es_tmr_size), > + false); > sev_es_tmr = NULL; > } > > @@ -1233,7 +1394,7 @@ void sev_pci_init(void) > } > > /* Obtain the TMR memory area for SEV-ES use */ > - tmr_page = alloc_pages(GFP_KERNEL, get_order(SEV_ES_TMR_SIZE)); > + tmr_page = __snp_alloc_firmware_pages(GFP_KERNEL, get_order(sev_es_tmr_size), false); > if (tmr_page) { > sev_es_tmr = page_address(tmr_page); > } else { > diff --git a/include/linux/psp-sev.h b/include/linux/psp-sev.h > index f2105a8755f9..00bd684dc094 100644 > --- a/include/linux/psp-sev.h > +++ b/include/linux/psp-sev.h > @@ -12,6 +12,8 @@ > #ifndef __PSP_SEV_H__ > #define __PSP_SEV_H__ > > +#include <linux/sev.h> > + > #include <uapi/linux/psp-sev.h> > > #ifdef CONFIG_X86 > @@ -919,6 +921,8 @@ int snp_guest_page_reclaim(struct sev_data_snp_page_reclaim *data, int *error); > int snp_guest_dbg_decrypt(struct sev_data_snp_dbg *data, int *error); > > void *psp_copy_user_blob(u64 uaddr, u32 len); > +void *snp_alloc_firmware_page(gfp_t mask); > +void snp_free_firmware_page(void *addr); > > #else /* !CONFIG_CRYPTO_DEV_SP_PSP */ > > @@ -960,6 +964,13 @@ static inline int snp_guest_dbg_decrypt(struct sev_data_snp_dbg *data, int *erro > return -ENODEV; > } > > +static inline void *snp_alloc_firmware_page(gfp_t mask) > +{ > + return NULL; > +} > + > +static inline void snp_free_firmware_page(void *addr) { } > + > #endif /* CONFIG_CRYPTO_DEV_SP_PSP */ > > #endif /* __PSP_SEV_H__ */ > -- > 2.17.1 > >
diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c index 01edad9116f2..34dc358b13b9 100644 --- a/drivers/crypto/ccp/sev-dev.c +++ b/drivers/crypto/ccp/sev-dev.c @@ -62,6 +62,14 @@ static int psp_timeout; #define SEV_ES_TMR_SIZE (1024 * 1024) static void *sev_es_tmr; +/* When SEV-SNP is enabled the TMR needs to be 2MB aligned and 2MB size. */ +#define SEV_SNP_ES_TMR_SIZE (2 * 1024 * 1024) + +static size_t sev_es_tmr_size = SEV_ES_TMR_SIZE; + +static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret); +static int sev_do_cmd(int cmd, void *data, int *psp_ret); + static inline bool sev_version_greater_or_equal(u8 maj, u8 min) { struct sev_device *sev = psp_master->sev_data; @@ -159,6 +167,156 @@ static int sev_cmd_buffer_len(int cmd) return 0; } +static void snp_leak_pages(unsigned long pfn, unsigned int npages) +{ + WARN(1, "psc failed, pfn 0x%lx pages %d (leaking)\n", pfn, npages); + while (npages--) { + memory_failure(pfn, 0); + dump_rmpentry(pfn); + pfn++; + } +} + +static int snp_reclaim_pages(unsigned long pfn, unsigned int npages, bool locked) +{ + struct sev_data_snp_page_reclaim data; + int ret, err, i, n = 0; + + for (i = 0; i < npages; i++) { + memset(&data, 0, sizeof(data)); + data.paddr = pfn << PAGE_SHIFT; + + if (locked) + ret = __sev_do_cmd_locked(SEV_CMD_SNP_PAGE_RECLAIM, &data, &err); + else + ret = sev_do_cmd(SEV_CMD_SNP_PAGE_RECLAIM, &data, &err); + if (ret) + goto cleanup; + + ret = rmp_make_shared(pfn, PG_LEVEL_4K); + if (ret) + goto cleanup; + + pfn++; + n++; + } + + return 0; + +cleanup: + /* + * If failed to reclaim the page then page is no longer safe to + * be released, leak it. + */ + snp_leak_pages(pfn, npages - n); + return ret; +} + +static inline int rmp_make_firmware(unsigned long pfn, int level) +{ + return rmp_make_private(pfn, 0, level, 0, true); +} + +static int snp_set_rmp_state(unsigned long paddr, unsigned int npages, bool to_fw, bool locked, + bool need_reclaim) +{ + unsigned long pfn = __sme_clr(paddr) >> PAGE_SHIFT; /* Cbit maybe set in the paddr */ + int rc, n = 0, i; + + for (i = 0; i < npages; i++) { + if (to_fw) + rc = rmp_make_firmware(pfn, PG_LEVEL_4K); + else + rc = need_reclaim ? snp_reclaim_pages(pfn, 1, locked) : + rmp_make_shared(pfn, PG_LEVEL_4K); + if (rc) + goto cleanup; + + pfn++; + n++; + } + + return 0; + +cleanup: + /* Try unrolling the firmware state changes */ + if (to_fw) { + /* + * Reclaim the pages which were already changed to the + * firmware state. + */ + snp_reclaim_pages(paddr >> PAGE_SHIFT, n, locked); + + return rc; + } + + /* + * If failed to change the page state to shared, then its not safe + * to release the page back to the system, leak it. + */ + snp_leak_pages(pfn, npages - n); + + return rc; +} + +static struct page *__snp_alloc_firmware_pages(gfp_t gfp_mask, int order, bool locked) +{ + unsigned long npages = 1ul << order, paddr; + struct sev_device *sev; + struct page *page; + + if (!psp_master || !psp_master->sev_data) + return ERR_PTR(-EINVAL); + + page = alloc_pages(gfp_mask, order); + if (!page) + return NULL; + + /* If SEV-SNP is initialized then add the page in RMP table. */ + sev = psp_master->sev_data; + if (!sev->snp_inited) + return page; + + paddr = __pa((unsigned long)page_address(page)); + if (snp_set_rmp_state(paddr, npages, true, locked, false)) + return NULL; + + return page; +} + +void *snp_alloc_firmware_page(gfp_t gfp_mask) +{ + struct page *page; + + page = __snp_alloc_firmware_pages(gfp_mask, 0, false); + + return page ? page_address(page) : NULL; +} +EXPORT_SYMBOL_GPL(snp_alloc_firmware_page); + +static void __snp_free_firmware_pages(struct page *page, int order, bool locked) +{ + unsigned long paddr, npages = 1ul << order; + + if (!page) + return; + + paddr = __pa((unsigned long)page_address(page)); + if (snp_set_rmp_state(paddr, npages, false, locked, true)) + return; + + __free_pages(page, order); +} + +void snp_free_firmware_page(void *addr) +{ + if (!addr) + return; + + __snp_free_firmware_pages(virt_to_page(addr), 0, false); +} +EXPORT_SYMBOL(snp_free_firmware_page); + static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret) { struct psp_device *psp = psp_master; @@ -281,7 +439,7 @@ static int __sev_platform_init_locked(int *error) data.flags |= SEV_INIT_FLAGS_SEV_ES; data.tmr_address = tmr_pa; - data.tmr_len = SEV_ES_TMR_SIZE; + data.tmr_len = sev_es_tmr_size; } rc = __sev_do_cmd_locked(SEV_CMD_INIT, &data, error); @@ -638,6 +796,8 @@ static int __sev_snp_init_locked(int *error) sev->snp_inited = true; dev_dbg(sev->dev, "SEV-SNP firmware initialized\n"); + sev_es_tmr_size = SEV_SNP_ES_TMR_SIZE; + return rc; } @@ -1161,8 +1321,9 @@ static void sev_firmware_shutdown(struct sev_device *sev) /* The TMR area was encrypted, flush it from the cache */ wbinvd_on_all_cpus(); - free_pages((unsigned long)sev_es_tmr, - get_order(SEV_ES_TMR_SIZE)); + __snp_free_firmware_pages(virt_to_page(sev_es_tmr), + get_order(sev_es_tmr_size), + false); sev_es_tmr = NULL; } @@ -1233,7 +1394,7 @@ void sev_pci_init(void) } /* Obtain the TMR memory area for SEV-ES use */ - tmr_page = alloc_pages(GFP_KERNEL, get_order(SEV_ES_TMR_SIZE)); + tmr_page = __snp_alloc_firmware_pages(GFP_KERNEL, get_order(sev_es_tmr_size), false); if (tmr_page) { sev_es_tmr = page_address(tmr_page); } else { diff --git a/include/linux/psp-sev.h b/include/linux/psp-sev.h index f2105a8755f9..00bd684dc094 100644 --- a/include/linux/psp-sev.h +++ b/include/linux/psp-sev.h @@ -12,6 +12,8 @@ #ifndef __PSP_SEV_H__ #define __PSP_SEV_H__ +#include <linux/sev.h> + #include <uapi/linux/psp-sev.h> #ifdef CONFIG_X86 @@ -919,6 +921,8 @@ int snp_guest_page_reclaim(struct sev_data_snp_page_reclaim *data, int *error); int snp_guest_dbg_decrypt(struct sev_data_snp_dbg *data, int *error); void *psp_copy_user_blob(u64 uaddr, u32 len); +void *snp_alloc_firmware_page(gfp_t mask); +void snp_free_firmware_page(void *addr); #else /* !CONFIG_CRYPTO_DEV_SP_PSP */ @@ -960,6 +964,13 @@ static inline int snp_guest_dbg_decrypt(struct sev_data_snp_dbg *data, int *erro return -ENODEV; } +static inline void *snp_alloc_firmware_page(gfp_t mask) +{ + return NULL; +} + +static inline void snp_free_firmware_page(void *addr) { } + #endif /* CONFIG_CRYPTO_DEV_SP_PSP */ #endif /* __PSP_SEV_H__ */
The behavior and requirement for the SEV-legacy command is altered when the SNP firmware is in the INIT state. See SEV-SNP firmware specification for more details. Allocate the Trusted Memory Region (TMR) as a 2mb sized/aligned region when SNP is enabled to satify new requirements for the SNP. Continue allocating a 1mb region for !SNP configuration. While at it, provide API that can be used by others to allocate a page that can be used by the firmware. The immediate user for this API will be the KVM driver. The KVM driver to need to allocate a firmware context page during the guest creation. The context page need to be updated by the firmware. See the SEV-SNP specification for further details. Signed-off-by: Brijesh Singh <brijesh.singh@amd.com> --- drivers/crypto/ccp/sev-dev.c | 169 ++++++++++++++++++++++++++++++++++- include/linux/psp-sev.h | 11 +++ 2 files changed, 176 insertions(+), 4 deletions(-)