On Sun, 2019-02-10 at 21:05 +0100, David Kozub wrote: > On Fri, 8 Feb 2019, Derrick, Jonathan wrote: > > > On Fri, 2019-02-01 at 21:50 +0100, David Kozub wrote: > > > From: Jonas Rabenstein > > > > > > Check whether the shadow mbr does fit in the provided space on > > > the > > > target. Also a proper firmware should handle this case and return > > > an > > > error we may prevent problems or even damage with crappy > > > firmwares. > > > > > > Signed-off-by: Jonas Rabenstein > > angen.de> > > > Reviewed-by: Scott Bauer > > > --- > > > block/opal_proto.h | 16 ++++++++++++++++ > > > block/sed-opal.c | 39 +++++++++++++++++++++++++++++++++++++++ > > > 2 files changed, 55 insertions(+) > > > > > > diff --git a/block/opal_proto.h b/block/opal_proto.h > > > index b6e352cfe982..5e8df3245eb0 100644 > > > --- a/block/opal_proto.h > > > +++ b/block/opal_proto.h > > > @@ -106,6 +106,7 @@ enum opal_uid { > > > OPAL_ENTERPRISE_BANDMASTER0_UID, > > > OPAL_ENTERPRISE_ERASEMASTER_UID, > > > /* tables */ > > > + OPAL_TABLE_TABLE, > > > OPAL_LOCKINGRANGE_GLOBAL, > > > OPAL_LOCKINGRANGE_ACE_RDLOCKED, > > > OPAL_LOCKINGRANGE_ACE_WRLOCKED, > > > @@ -160,6 +161,21 @@ enum opal_token { > > > OPAL_STARTCOLUMN = 0x03, > > > OPAL_ENDCOLUMN = 0x04, > > > OPAL_VALUES = 0x01, > > > + /* table table */ > > > + OPAL_TABLE_UID = 0x00, > > > + OPAL_TABLE_NAME = 0x01, > > > + OPAL_TABLE_COMMON = 0x02, > > > + OPAL_TABLE_TEMPLATE = 0x03, > > > + OPAL_TABLE_KIND = 0x04, > > > + OPAL_TABLE_COLUMN = 0x05, > > > + OPAL_TABLE_COLUMNS = 0x06, > > > + OPAL_TABLE_ROWS = 0x07, > > > + OPAL_TABLE_ROWS_FREE = 0x08, > > > + OPAL_TABLE_ROW_BYTES = 0x09, > > > + OPAL_TABLE_LASTID = 0x0A, > > > + OPAL_TABLE_MIN = 0x0B, > > > + OPAL_TABLE_MAX = 0x0C, > > > + > > > /* authority table */ > > > OPAL_PIN = 0x03, > > > /* locking tokens */ > > > diff --git a/block/sed-opal.c b/block/sed-opal.c > > > index 2459ac4d523b..3493bb979978 100644 > > > --- a/block/sed-opal.c > > > +++ b/block/sed-opal.c > > > @@ -139,6 +139,8 @@ static const u8 opaluid[][OPAL_UID_LENGTH] = > > > { > > > > > > /* tables */ > > > > > > + [OPAL_TABLE_TABLE] > > > + { 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x01 > > > }, > > > [OPAL_LOCKINGRANGE_GLOBAL] = > > > { 0x00, 0x00, 0x08, 0x02, 0x00, 0x00, 0x00, 0x01 > > > }, > > > [OPAL_LOCKINGRANGE_ACE_RDLOCKED] = > > > @@ -1120,6 +1122,29 @@ static int generic_get_column(struct > > > opal_dev *dev, const u8 *table, > > > return finalize_and_send(dev, parse_and_check_status); > > > } > > > > > > +/* > > > + * see TCG SAS 5.3.2.3 for a description of the available > > > columns > > > + * > > > + * the result is provided in dev->resp->tok[4] > > > + */ > > > +static int generic_get_table_info(struct opal_dev *dev, enum > > > opal_uid table, > > > + u64 column) > > > +{ > > > + u8 uid[OPAL_UID_LENGTH]; > > > + const unsigned int half = OPAL_UID_LENGTH/2; > > > + > > > + /* sed-opal UIDs can be split in two halves: > > > + * first: actual table index > > > + * second: relative index in the table > > > + * so we have to get the first half of the > > > OPAL_TABLE_TABLE and use the > > > + * first part of the target table as relative index into > > > that table > > > + */ > > > + memcpy(uid, opaluid[OPAL_TABLE_TABLE], half); > > > + memcpy(uid+half, opaluid[table], half); > > > + > > > + return generic_get_column(dev, uid, column); > > > +} > > > + > > > static int gen_key(struct opal_dev *dev, void *data) > > > { > > > u8 uid[OPAL_UID_LENGTH]; > > > @@ -1535,6 +1560,20 @@ static int write_shadow_mbr(struct > > > opal_dev *dev, void *data) > > > u64 len; > > > int err = 0; > > > > > > + /* do we fit in the available shadow mbr space? */ > > > + err = generic_get_table_info(dev, OPAL_MBR, > > > OPAL_TABLE_ROWS); > > > > Wouldn't you need to multiply this by result from > > OPAL_TABLE_ROWBYTES? > > What does ROWBYTES return for you? > > Hi Jon, > > reading the spec[1], I think it defines the MBR table to be a "byte > table" > (see 5.7.2.6 MBR (Byte Table)). For byte tables, it says (see > 3.2.5.1 > Kinds of Tables) "A byte table has one unnamed column of type > bytes_1." I > think this implies that each row is 1 byte and so number of rows = > size of > table in rows. > > When I actually try to get OPAL_TABLE_ROWS abd OPAL_TABLE_ROWBYTES of > the > MBR table from a Samsung 840 EVO, I get: > * OPAL_TABLE_ROWS 134217728 which is 128 MiB > * OPAL_TABLE_ROWBYTES 0 > > I'm not sure if I'm doing something wrong here. I just added: > > err = generic_get_table_info(dev, OPAL_MBR, > OPAL_TABLE_ROW_BYTES); > if (err) { > pr_debug("MBR: could not get shadow row bytes > size\n"); > return err; > } > > row_bytes = response_get_u64(&dev->parsed, 4); > > Best regards, > David > > [1] https://trustedcomputinggroup.org/wp-content/uploads/TCG_Storage_ > Architecture_Core_Spec_v2.01_r1.00.pdf I also see ROWS=0x8000000 and ROWBYTES=0 on an Intel drive, so my interpretation of rowbytes was probably incorrect. Reviewed-by: Jon Derrick