| Message ID | 442637364b55c8a721f72a201e838eb5c271e0eb.1721186590.git.kai.huang@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | TDX host: metadata reading tweaks, bug fix and info dump | expand |
Kai Huang wrote: > The TDX module provides "global metadata fields" for software to query. > Each metadata field is accessible by a unique "metadata field ID". TDX > supports 8/16/32/64 bits metadata element sizes. The size of each > metadata field is encoded in its associated metadata field ID. > > For now the kernel only reads "TD Memory Region" (TDMR) related global > metadata fields for module initialization. All these metadata fields > are 16-bit, and the kernel only supports reading 16-bit fields. > > Future changes will need to read more metadata fields with other element > sizes. To resolve this once for all, extend the existing metadata > reading code to support reading all element sizes. > > Signed-off-by: Kai Huang <kai.huang@intel.com> > Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> > --- > > v1 -> v2 (Nikolay): > - MD_FIELD_BYTES() -> MD_FIELD_ELE_SIZE(). > - 'bytes' -> 'size' in stbuf_read_sysmd_field(). > > --- > arch/x86/virt/vmx/tdx/tdx.c | 29 ++++++++++++++++------------- > arch/x86/virt/vmx/tdx/tdx.h | 3 ++- > 2 files changed, 18 insertions(+), 14 deletions(-) > > diff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c > index 2ce03c3ea017..4644b324ff86 100644 > --- a/arch/x86/virt/vmx/tdx/tdx.c > +++ b/arch/x86/virt/vmx/tdx/tdx.c > @@ -270,23 +270,25 @@ static int read_sys_metadata_field(u64 field_id, u64 *data) > return 0; > } > > -static int read_sys_metadata_field16(u64 field_id, > - int offset, > - void *stbuf) > +/* > + * Read one global metadata field and store the data to a location of a > + * given buffer specified by the offset and size (in bytes). > + */ > +static int stbuf_read_sysmd_field(u64 field_id, void *stbuf, int offset, > + int size) > { > - u16 *member = stbuf + offset; > + void *member = stbuf + offset; > u64 tmp; > int ret; > > - if (WARN_ON_ONCE(MD_FIELD_ID_ELE_SIZE_CODE(field_id) != > - MD_FIELD_ID_ELE_SIZE_16BIT)) > + if (WARN_ON_ONCE(MD_FIELD_ELE_SIZE(field_id) != size)) > return -EINVAL; Per the last patch, re: unrolling @fields, it's unfortunate to have a runtime warning for something that could have been verified at compile time.
diff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c index 2ce03c3ea017..4644b324ff86 100644 --- a/arch/x86/virt/vmx/tdx/tdx.c +++ b/arch/x86/virt/vmx/tdx/tdx.c @@ -270,23 +270,25 @@ static int read_sys_metadata_field(u64 field_id, u64 *data) return 0; } -static int read_sys_metadata_field16(u64 field_id, - int offset, - void *stbuf) +/* + * Read one global metadata field and store the data to a location of a + * given buffer specified by the offset and size (in bytes). + */ +static int stbuf_read_sysmd_field(u64 field_id, void *stbuf, int offset, + int size) { - u16 *member = stbuf + offset; + void *member = stbuf + offset; u64 tmp; int ret; - if (WARN_ON_ONCE(MD_FIELD_ID_ELE_SIZE_CODE(field_id) != - MD_FIELD_ID_ELE_SIZE_16BIT)) + if (WARN_ON_ONCE(MD_FIELD_ELE_SIZE(field_id) != size)) return -EINVAL; ret = read_sys_metadata_field(field_id, &tmp); if (ret) return ret; - *member = tmp; + memcpy(member, &tmp, size); return 0; } @@ -294,11 +296,13 @@ static int read_sys_metadata_field16(u64 field_id, struct field_mapping { u64 field_id; int offset; + int size; }; -#define TD_SYSINFO_MAP(_field_id, _struct, _member) \ - { .field_id = MD_FIELD_ID_##_field_id, \ - .offset = offsetof(_struct, _member) } +#define TD_SYSINFO_MAP(_field_id, _struct, _member) \ + { .field_id = MD_FIELD_ID_##_field_id, \ + .offset = offsetof(_struct, _member), \ + .size = sizeof(typeof(((_struct *)0)->_member)) } #define TD_SYSINFO_MAP_TDMR_INFO(_field_id, _member) \ TD_SYSINFO_MAP(_field_id, struct tdx_tdmr_sysinfo, _member) @@ -319,9 +323,8 @@ static int get_tdx_tdmr_sysinfo(struct tdx_tdmr_sysinfo *tdmr_sysinfo) /* Populate 'tdmr_sysinfo' fields using the mapping structure above: */ for (i = 0; i < ARRAY_SIZE(fields); i++) { - ret = read_sys_metadata_field16(fields[i].field_id, - fields[i].offset, - tdmr_sysinfo); + ret = stbuf_read_sysmd_field(fields[i].field_id, tdmr_sysinfo, + fields[i].offset, fields[i].size); if (ret) return ret; } diff --git a/arch/x86/virt/vmx/tdx/tdx.h b/arch/x86/virt/vmx/tdx/tdx.h index b701f69485d3..fdb879ef6c45 100644 --- a/arch/x86/virt/vmx/tdx/tdx.h +++ b/arch/x86/virt/vmx/tdx/tdx.h @@ -53,7 +53,8 @@ #define MD_FIELD_ID_ELE_SIZE_CODE(_field_id) \ (((_field_id) & GENMASK_ULL(33, 32)) >> 32) -#define MD_FIELD_ID_ELE_SIZE_16BIT 1 +#define MD_FIELD_ELE_SIZE(_field_id) \ + (1 << MD_FIELD_ID_ELE_SIZE_CODE(_field_id)) struct tdmr_reserved_area { u64 offset;