[acpi] Remove userptr_t from ACPI table parsing

Simplify the ACPI table parsing code by assuming that all table
content is fully accessible via pointer dereferences.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

src/arch/x86/include/ipxe/rsdp.h

@@ -20,9 +20,9 @@ FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
  *
  * @v signature		Requested table signature
  * @v index		Requested index of table with this signature
- * @ret table		Table, or UNULL if not found
+ * @ret table		Table, or NULL if not found
  */
-static inline __attribute__ (( always_inline )) userptr_t
+static inline __attribute__ (( always_inline )) const struct acpi_header *
 ACPI_INLINE ( rsdp, acpi_find ) ( uint32_t signature, unsigned int index ) {
 
 	return acpi_find_via_rsdt ( signature, index );

src/arch/x86/interface/pcbios/acpi_timer.c

@@ -102,20 +102,19 @@ static void acpi_udelay ( unsigned long usecs ) {
  * @ret rc		Return status code
  */
 static int acpi_timer_probe ( void ) {
-	struct acpi_fadt fadtab;
-	userptr_t fadt;
+	const struct acpi_fadt *fadt;
 	unsigned int pm_tmr_blk;
 
 	/* Locate FADT */
-	fadt = acpi_table ( FADT_SIGNATURE, 0 );
+	fadt = container_of ( acpi_table ( FADT_SIGNATURE, 0 ),
+			      struct acpi_fadt, acpi );
 	if ( ! fadt ) {
 		DBGC ( &acpi_timer, "ACPI could not find FADT\n" );
 		return -ENOENT;
 	}
 
 	/* Read FADT */
-	copy_from_user ( &fadtab, fadt, 0, sizeof ( fadtab ) );
-	pm_tmr_blk = le32_to_cpu ( fadtab.pm_tmr_blk );
+	pm_tmr_blk = le32_to_cpu ( fadt->pm_tmr_blk );
 	if ( ! pm_tmr_blk ) {
 		DBGC ( &acpi_timer, "ACPI has no timer\n" );
 		return -ENOENT;

src/arch/x86/interface/pcbios/acpipwr.c

@@ -62,8 +62,8 @@ FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
  * uglier hacks I have ever implemented, but it's still prettier than
  * the ACPI specification itself.
  */
-static int acpi_extract_sx ( userptr_t zsdt, size_t len, size_t offset,
-			     void *data ) {
+static int acpi_extract_sx ( const struct acpi_header *zsdt, size_t len,
+			     size_t offset, void *data ) {
 	unsigned int *sx = data;
 	uint8_t bytes[4];
 	uint8_t *byte;
@@ -77,7 +77,8 @@ static int acpi_extract_sx ( userptr_t zsdt, size_t len, size_t offset,
 	}
 
 	/* Read first four bytes of value */
-	copy_from_user ( bytes, zsdt, offset, sizeof ( bytes ) );
+	memcpy ( bytes, ( ( ( const void * ) zsdt ) + offset ),
+		 sizeof ( bytes ) );
 	DBGC ( colour, "ACPI found \\_Sx containing %02x:%02x:%02x:%02x\n",
 	       bytes[0], bytes[1], bytes[2], bytes[3] );
 
@@ -111,8 +112,7 @@ static int acpi_extract_sx ( userptr_t zsdt, size_t len, size_t offset,
  * @ret rc		Return status code
  */
 int acpi_poweroff ( void ) {
-	struct acpi_fadt fadtab;
-	userptr_t fadt;
+	const struct acpi_fadt *fadt;
 	unsigned int pm1a_cnt_blk;
 	unsigned int pm1b_cnt_blk;
 	unsigned int pm1a_cnt;
@@ -123,16 +123,16 @@ int acpi_poweroff ( void ) {
 	int rc;
 
 	/* Locate FADT */
-	fadt = acpi_table ( FADT_SIGNATURE, 0 );
+	fadt = container_of ( acpi_table ( FADT_SIGNATURE, 0 ),
+			      struct acpi_fadt, acpi );
 	if ( ! fadt ) {
 		DBGC ( colour, "ACPI could not find FADT\n" );
 		return -ENOENT;
 	}
 
 	/* Read FADT */
-	copy_from_user ( &fadtab, fadt, 0, sizeof ( fadtab ) );
-	pm1a_cnt_blk = le32_to_cpu ( fadtab.pm1a_cnt_blk );
-	pm1b_cnt_blk = le32_to_cpu ( fadtab.pm1b_cnt_blk );
+	pm1a_cnt_blk = le32_to_cpu ( fadt->pm1a_cnt_blk );
+	pm1b_cnt_blk = le32_to_cpu ( fadt->pm1b_cnt_blk );
 	pm1a_cnt = ( pm1a_cnt_blk + ACPI_PM1_CNT );
 	pm1b_cnt = ( pm1b_cnt_blk + ACPI_PM1_CNT );
 

src/arch/x86/interface/pcbios/rsdp.c

@@ -53,50 +53,51 @@ FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
  *
  * @v start		Start address to search
  * @v len		Length to search
- * @ret rsdt		ACPI root system description table, or UNULL
+ * @ret rsdt		ACPI root system description table, or NULL
  */
-static userptr_t rsdp_find_rsdt_range ( userptr_t start, size_t len ) {
+static const struct acpi_rsdt * rsdp_find_rsdt_range ( const void *start,
+						       size_t len ) {
 	static const char signature[8] = RSDP_SIGNATURE;
-	struct acpi_rsdp rsdp;
-	userptr_t rsdt;
+	const struct acpi_rsdp *rsdp;
+	const struct acpi_rsdt *rsdt;
 	size_t offset;
 	uint8_t sum;
 	unsigned int i;
 
 	/* Search for RSDP */
-	for ( offset = 0 ; ( ( offset + sizeof ( rsdp ) ) < len ) ;
+	for ( offset = 0 ; ( ( offset + sizeof ( *rsdp ) ) < len ) ;
 	      offset += RSDP_STRIDE ) {
 
 		/* Check signature and checksum */
-		copy_from_user ( &rsdp, start, offset, sizeof ( rsdp ) );
-		if ( memcmp ( rsdp.signature, signature,
+		rsdp = ( start + offset );
+		if ( memcmp ( rsdp->signature, signature,
 			      sizeof ( signature ) ) != 0 )
 			continue;
-		for ( sum = 0, i = 0 ; i < sizeof ( rsdp ) ; i++ )
-			sum += *( ( ( uint8_t * ) &rsdp ) + i );
+		for ( sum = 0, i = 0 ; i < sizeof ( *rsdp ) ; i++ )
+			sum += *( ( ( uint8_t * ) rsdp ) + i );
 		if ( sum != 0 )
 			continue;
 
 		/* Extract RSDT */
-		rsdt = phys_to_virt ( le32_to_cpu ( rsdp.rsdt ) );
+		rsdt = phys_to_virt ( le32_to_cpu ( rsdp->rsdt ) );
 		DBGC ( rsdt, "RSDT %#08lx found via RSDP %#08lx\n",
 		       virt_to_phys ( rsdt ),
 		       ( virt_to_phys ( start ) + offset ) );
 		return rsdt;
 	}
 
-	return UNULL;
+	return NULL;
 }
 
 /**
  * Locate ACPI root system description table
  *
- * @ret rsdt		ACPI root system description table, or UNULL
+ * @ret rsdt		ACPI root system description table, or NULL
  */
-static userptr_t rsdp_find_rsdt ( void ) {
-	static userptr_t rsdt;
+static const struct acpi_rsdt * rsdp_find_rsdt ( void ) {
+	static const struct acpi_rsdt *rsdt;
+	const void *ebda;
 	uint16_t ebda_seg;
-	userptr_t ebda;
 	size_t ebda_len;
 
 	/* Return existing RSDT if already found */
@@ -119,7 +120,7 @@ static userptr_t rsdp_find_rsdt ( void ) {
 	if ( rsdt )
 		return rsdt;
 
-	return UNULL;
+	return NULL;
 }
 
 PROVIDE_ACPI ( rsdp, acpi_find_rsdt, rsdp_find_rsdt );

src/core/acpi.c

@@ -23,6 +23,7 @@
 
 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 
+#include <string.h>
 #include <errno.h>
 #include <byteswap.h>
 #include <ipxe/uaccess.h>
@@ -54,25 +55,17 @@ typeof ( acpi_find ) *acpi_finder __attribute__ (( weak )) = acpi_find;
 /**
  * Compute ACPI table checksum
  *
- * @v table		Any ACPI table
+ * @v acpi		Any ACPI table header
  * @ret checksum	0 if checksum is good
  */
-static uint8_t acpi_checksum ( userptr_t table ) {
-	struct acpi_header acpi;
+static uint8_t acpi_checksum ( const struct acpi_header *acpi ) {
+	const uint8_t *byte = ( ( const void * ) acpi );
+	size_t len = le32_to_cpu ( acpi->length );
 	uint8_t sum = 0;
-	uint8_t data = 0;
-	unsigned int i;
-
-	/* Read table length */
-	copy_from_user ( &acpi.length, table,
-			 offsetof ( typeof ( acpi ), length ),
-			 sizeof ( acpi.length ) );
 
 	/* Compute checksum */
-	for ( i = 0 ; i < le32_to_cpu ( acpi.length ) ; i++ ) {
-		copy_from_user ( &data, table, i, sizeof ( data ) );
-		sum += data;
-	}
+	while ( len-- )
+		sum += *(byte++);
 
 	return sum;
 }
@@ -85,7 +78,7 @@ static uint8_t acpi_checksum ( userptr_t table ) {
 void acpi_fix_checksum ( struct acpi_header *acpi ) {
 
 	/* Update checksum */
-	acpi->checksum -= acpi_checksum ( virt_to_user ( acpi ) );
+	acpi->checksum -= acpi_checksum ( acpi );
 }
 
 /**
@@ -93,9 +86,10 @@ void acpi_fix_checksum ( struct acpi_header *acpi ) {
  *
  * @v signature		Requested table signature
  * @v index		Requested index of table with this signature
- * @ret table		Table, or UNULL if not found
+ * @ret table		Table, or NULL if not found
  */
-userptr_t acpi_table ( uint32_t signature, unsigned int index ) {
+const struct acpi_header * acpi_table ( uint32_t signature,
+					unsigned int index ) {
 
 	return ( *acpi_finder ) ( signature, index );
 }
@@ -105,14 +99,12 @@ userptr_t acpi_table ( uint32_t signature, unsigned int index ) {
  *
  * @v signature		Requested table signature
  * @v index		Requested index of table with this signature
- * @ret table		Table, or UNULL if not found
+ * @ret table		Table, or NULL if not found
  */
-userptr_t acpi_find_via_rsdt ( uint32_t signature, unsigned int index ) {
-	struct acpi_header acpi;
-	struct acpi_rsdt *rsdtab;
-	typeof ( rsdtab->entry[0] ) entry;
-	userptr_t rsdt;
-	userptr_t table;
+const struct acpi_header * acpi_find_via_rsdt ( uint32_t signature,
+						unsigned int index ) {
+	const struct acpi_rsdt *rsdt;
+	const struct acpi_header *table;
 	size_t len;
 	unsigned int count;
 	unsigned int i;
@@ -121,45 +113,38 @@ userptr_t acpi_find_via_rsdt ( uint32_t signature, unsigned int index ) {
 	rsdt = acpi_find_rsdt();
 	if ( ! rsdt ) {
 		DBG ( "RSDT not found\n" );
-		return UNULL;
+		return NULL;
 	}
 
 	/* Read RSDT header */
-	copy_from_user ( &acpi, rsdt, 0, sizeof ( acpi ) );
-	if ( acpi.signature != cpu_to_le32 ( RSDT_SIGNATURE ) ) {
+	if ( rsdt->acpi.signature != cpu_to_le32 ( RSDT_SIGNATURE ) ) {
 		DBGC ( colour, "RSDT %#08lx has invalid signature:\n",
 		       virt_to_phys ( rsdt ) );
-		DBGC_HDA ( colour, virt_to_phys ( rsdt ), &acpi,
-			   sizeof ( acpi ) );
-		return UNULL;
+		DBGC_HDA ( colour, virt_to_phys ( rsdt ), &rsdt->acpi,
+			   sizeof ( rsdt->acpi ) );
+		return NULL;
 	}
-	len = le32_to_cpu ( acpi.length );
-	if ( len < sizeof ( rsdtab->acpi ) ) {
+	len = le32_to_cpu ( rsdt->acpi.length );
+	if ( len < sizeof ( rsdt->acpi ) ) {
 		DBGC ( colour, "RSDT %#08lx has invalid length:\n",
 		       virt_to_phys ( rsdt ) );
-		DBGC_HDA ( colour, virt_to_phys ( rsdt ), &acpi,
-			   sizeof ( acpi ) );
-		return UNULL;
+		DBGC_HDA ( colour, virt_to_phys ( rsdt ), &rsdt->acpi,
+			   sizeof ( rsdt->acpi ) );
+		return NULL;
 	}
 
 	/* Calculate number of entries */
-	count = ( ( len - sizeof ( rsdtab->acpi ) ) / sizeof ( entry ) );
+	count = ( ( len - sizeof ( rsdt->acpi ) ) /
+		  sizeof ( rsdt->entry[0] ) );
 
 	/* Search through entries */
 	for ( i = 0 ; i < count ; i++ ) {
 
-		/* Get table address */
-		copy_from_user ( &entry, rsdt,
-				 offsetof ( typeof ( *rsdtab ), entry[i] ),
-				 sizeof ( entry ) );
-
 		/* Read table header */
-		table = phys_to_virt ( entry );
-		copy_from_user ( &acpi.signature, table, 0,
-				 sizeof ( acpi.signature ) );
+		table = phys_to_virt ( rsdt->entry[i] );
 
 		/* Check table signature */
-		if ( acpi.signature != cpu_to_le32 ( signature ) )
+		if ( table->signature != cpu_to_le32 ( signature ) )
 			continue;
 
 		/* Check index */
@@ -169,13 +154,13 @@ userptr_t acpi_find_via_rsdt ( uint32_t signature, unsigned int index ) {
 		/* Check table integrity */
 		if ( acpi_checksum ( table ) != 0 ) {
 			DBGC ( colour, "RSDT %#08lx found %s with bad "
-			       "checksum at %08lx\n", virt_to_phys ( rsdt ),
+			       "checksum at %#08lx\n", virt_to_phys ( rsdt ),
 			       acpi_name ( signature ),
 			       virt_to_phys ( table ) );
 			break;
 		}
 
-		DBGC ( colour, "RSDT %#08lx found %s at %08lx\n",
+		DBGC ( colour, "RSDT %#08lx found %s at %#08lx\n",
 		       virt_to_phys ( rsdt ), acpi_name ( signature ),
 		       virt_to_phys ( table ) );
 		return table;
@@ -183,7 +168,7 @@ userptr_t acpi_find_via_rsdt ( uint32_t signature, unsigned int index ) {
 
 	DBGC ( colour, "RSDT %#08lx could not find %s\n",
 	       virt_to_phys ( rsdt ), acpi_name ( signature ) );
-	return UNULL;
+	return NULL;
 }
 
 /**
@@ -195,26 +180,27 @@ userptr_t acpi_find_via_rsdt ( uint32_t signature, unsigned int index ) {
  * @v extract		Extraction method
  * @ret rc		Return status code
  */
-static int acpi_zsdt ( userptr_t zsdt, uint32_t signature, void *data,
-		       int ( * extract ) ( userptr_t zsdt, size_t len,
-					   size_t offset, void *data ) ) {
-	struct acpi_header acpi;
+static int acpi_zsdt ( const struct acpi_header *zsdt,
+		       uint32_t signature, void *data,
+		       int ( * extract ) ( const struct acpi_header *zsdt,
+					   size_t len, size_t offset,
+					   void *data ) ) {
 	uint32_t buf;
 	size_t offset;
 	size_t len;
 	int rc;
 
 	/* Read table header */
-	copy_from_user ( &acpi, zsdt, 0, sizeof ( acpi ) );
-	len = le32_to_cpu ( acpi.length );
+	len = le32_to_cpu ( zsdt->length );
 
 	/* Locate signature */
-	for ( offset = sizeof ( acpi ) ;
+	for ( offset = sizeof ( *zsdt ) ;
 	      ( ( offset + sizeof ( buf ) /* signature */ ) < len ) ;
 	      offset++ ) {
 
 		/* Check signature */
-		copy_from_user ( &buf, zsdt, offset, sizeof ( buf ) );
+		memcpy ( &buf, ( ( ( const void * ) zsdt ) + offset ),
+			 sizeof ( buf ) );
 		if ( buf != cpu_to_le32 ( signature ) )
 			continue;
 		DBGC ( zsdt, "DSDT/SSDT %#08lx found %s at offset %#zx\n",
@@ -238,20 +224,20 @@ static int acpi_zsdt ( userptr_t zsdt, uint32_t signature, void *data,
  * @ret rc		Return status code
  */
 int acpi_extract ( uint32_t signature, void *data,
-		   int ( * extract ) ( userptr_t zsdt, size_t len,
-				       size_t offset, void *data ) ) {
-	struct acpi_fadt fadtab;
-	userptr_t fadt;
-	userptr_t dsdt;
-	userptr_t ssdt;
+		   int ( * extract ) ( const struct acpi_header *zsdt,
+				       size_t len, size_t offset,
+				       void *data ) ) {
+	const struct acpi_fadt *fadt;
+	const struct acpi_header *dsdt;
+	const struct acpi_header *ssdt;
 	unsigned int i;
 	int rc;
 
 	/* Try DSDT first */
-	fadt = acpi_table ( FADT_SIGNATURE, 0 );
+	fadt = container_of ( acpi_table ( FADT_SIGNATURE, 0 ),
+			      struct acpi_fadt, acpi );
 	if ( fadt ) {
-		copy_from_user ( &fadtab, fadt, 0, sizeof ( fadtab ) );
-		dsdt = phys_to_virt ( fadtab.dsdt );
+		dsdt = phys_to_virt ( fadt->dsdt );
 		if ( ( rc = acpi_zsdt ( dsdt, signature, data,
 					extract ) ) == 0 )
 			return 0;

src/core/acpi_settings.c

@@ -64,14 +64,15 @@ static int acpi_settings_applies ( struct settings *settings __unused,
 static int acpi_settings_fetch ( struct settings *settings,
 				 struct setting *setting,
 				 void *data, size_t len ) {
-	struct acpi_header acpi;
+	const struct acpi_header *acpi;
+	const uint8_t *src;
+	uint8_t *dst;
 	uint32_t tag_high;
 	uint32_t tag_low;
 	uint32_t tag_signature;
 	unsigned int tag_index;
 	size_t tag_offset;
 	size_t tag_len;
-	userptr_t table;
 	size_t offset;
 	size_t max_len;
 	int delta;
@@ -88,15 +89,12 @@ static int acpi_settings_fetch ( struct settings *settings,
 	       acpi_name ( tag_signature ), tag_index, tag_offset, tag_len );
 
 	/* Locate ACPI table */
-	table = acpi_table ( tag_signature, tag_index );
-	if ( ! table )
+	acpi = acpi_table ( tag_signature, tag_index );
+	if ( ! acpi )
 		return -ENOENT;
 
-	/* Read table header */
-	copy_from_user ( &acpi, table, 0, sizeof ( acpi ) );
-
 	/* Calculate starting offset and maximum available length */
-	max_len = le32_to_cpu ( acpi.length );
+	max_len = le32_to_cpu ( acpi->length );
 	if ( tag_offset > max_len )
 		return -ENOENT;
 	offset = tag_offset;
@@ -115,10 +113,11 @@ static int acpi_settings_fetch ( struct settings *settings,
 	}
 
 	/* Read data */
+	src = ( ( ( const void * ) acpi ) + offset );
+	dst = data;
 	for ( i = 0 ; ( ( i < max_len ) && ( i < len ) ) ; i++ ) {
-		copy_from_user ( data, table, offset, 1 );
-		data++;
-		offset += delta;
+		*(dst++) = *src;
+		src += delta;
 	}
 
 	/* Set type if not already specified */

src/core/acpimac.c

@@ -142,8 +142,9 @@ static struct acpimac_extractor acpimac_rtxmac = {
  * string that appears shortly after an "AMAC" or "MACA" signature.
  * This should work for most implementations encountered in practice.
  */
-static int acpimac_extract ( userptr_t zsdt, size_t len, size_t offset,
-			     void *data, struct acpimac_extractor *extractor ){
+static int acpimac_extract ( const struct acpi_header *zsdt, size_t len,
+			     size_t offset, void *data,
+			     struct acpimac_extractor *extractor ) {
 	size_t prefix_len = strlen ( extractor->prefix );
 	uint8_t *hw_addr = data;
 	size_t skip = 0;
@@ -161,7 +162,7 @@ static int acpimac_extract ( userptr_t zsdt, size_t len, size_t offset,
 	      skip++ ) {
 
 		/* Read value */
-		copy_from_user ( buf, zsdt, ( offset + skip ),
+		memcpy ( buf, ( ( ( const void * ) zsdt ) + offset + skip ),
 			 sizeof ( buf ) );
 
 		/* Check for expected format */
@@ -203,8 +204,8 @@ static int acpimac_extract ( userptr_t zsdt, size_t len, size_t offset,
  * @v data		Data buffer
  * @ret rc		Return status code
  */
-static int acpimac_extract_auxmac ( userptr_t zsdt, size_t len, size_t offset,
-				    void *data ) {
+static int acpimac_extract_auxmac ( const struct acpi_header *zsdt,
+				    size_t len, size_t offset, void *data ) {
 
 	return acpimac_extract ( zsdt, len, offset, data, &acpimac_auxmac );
 }
@@ -218,8 +219,8 @@ static int acpimac_extract_auxmac ( userptr_t zsdt, size_t len, size_t offset,
  * @v data		Data buffer
  * @ret rc		Return status code
  */
-static int acpimac_extract_rtxmac ( userptr_t zsdt, size_t len, size_t offset,
-				    void *data ) {
+static int acpimac_extract_rtxmac ( const struct acpi_header *zsdt,
+				    size_t len, size_t offset, void *data ) {
 
 	return acpimac_extract ( zsdt, len, offset, data, &acpimac_rtxmac );
 }

src/drivers/bus/ecam.c

@@ -46,49 +46,43 @@ static struct ecam_mapping ecam;
  */
 static int ecam_find ( uint32_t busdevfn, struct pci_range *range,
 		       struct ecam_allocation *alloc ) {
-	struct ecam_allocation tmp;
+	struct ecam_table *mcfg;
+	struct ecam_allocation *tmp;
 	unsigned int best = 0;
-	unsigned int offset;
 	unsigned int count;
 	unsigned int index;
-	userptr_t mcfg;
-	uint32_t length;
+	unsigned int i;
 	uint32_t start;
 
 	/* Return empty range on error */
 	range->count = 0;
 
 	/* Locate MCFG table */
-	mcfg = acpi_table ( ECAM_SIGNATURE, 0 );
+	mcfg = container_of ( acpi_table ( ECAM_SIGNATURE, 0 ),
+			      struct ecam_table, acpi );
 	if ( ! mcfg ) {
 		DBGC ( &ecam, "ECAM found no MCFG table\n" );
 		return -ENOTSUP;
 	}
 
-	/* Get length of table */
-	copy_from_user ( &length, mcfg,
-			 offsetof ( struct ecam_table, acpi.length ),
-			 sizeof ( length ) );
-
 	/* Iterate over allocations */
-	for ( offset = offsetof ( struct ecam_table, alloc ) ;
-	      ( offset + sizeof ( tmp ) ) <= le32_to_cpu ( length ) ;
-	      offset += sizeof ( tmp ) ) {
+	for ( i = 0 ; ( offsetof ( typeof ( *mcfg ), alloc[ i + 1 ] ) <=
+			le32_to_cpu ( mcfg->acpi.length ) ) ; i++ ) {
 
 		/* Read allocation */
-		copy_from_user ( &tmp, mcfg, offset, sizeof ( tmp ) );
+		tmp = &mcfg->alloc[i];
 		DBGC2 ( &ecam, "ECAM %04x:[%02x-%02x] has base %08llx\n",
-			le16_to_cpu ( tmp.segment ), tmp.start, tmp.end,
-			( ( unsigned long long ) le64_to_cpu ( tmp.base ) ) );
-		start = PCI_BUSDEVFN ( le16_to_cpu ( tmp.segment ),
-				       tmp.start, 0, 0 );
-		count = PCI_BUSDEVFN ( 0, ( tmp.end - tmp.start + 1 ), 0, 0 );
+			le16_to_cpu ( tmp->segment ), tmp->start, tmp->end,
+			( ( unsigned long long ) le64_to_cpu ( tmp->base ) ) );
+		start = PCI_BUSDEVFN ( le16_to_cpu ( tmp->segment ),
+				       tmp->start, 0, 0 );
+		count = PCI_BUSDEVFN ( 0, ( tmp->end - tmp->start + 1 ), 0, 0 );
 
 		/* Check for a matching or new closest allocation */
 		index = ( busdevfn - start );
 		if ( ( index < count ) || ( index > best ) ) {
 			if ( alloc )
-				memcpy ( alloc, &tmp, sizeof ( *alloc ) );
+				memcpy ( alloc, tmp, sizeof ( *alloc ) );
 			range->start = start;
 			range->count = count;
 			best = index;

src/include/ipxe/acpi.h

@@ -14,7 +14,6 @@ FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 #include <ipxe/refcnt.h>
 #include <ipxe/list.h>
 #include <ipxe/interface.h>
-#include <ipxe/uaccess.h>
 #include <ipxe/tables.h>
 #include <ipxe/api.h>
 #include <config/general.h>
@@ -355,7 +354,8 @@ struct acpi_model {
 #define PROVIDE_ACPI_INLINE( _subsys, _api_func ) \
 	PROVIDE_SINGLE_API_INLINE ( ACPI_PREFIX_ ## _subsys, _api_func )
 
-extern userptr_t acpi_find_via_rsdt ( uint32_t signature, unsigned int index );
+extern const struct acpi_header * acpi_find_via_rsdt ( uint32_t signature,
+						       unsigned int index );
 
 /* Include all architecture-independent ACPI API headers */
 #include <ipxe/null_acpi.h>
@@ -368,31 +368,35 @@ extern userptr_t acpi_find_via_rsdt ( uint32_t signature, unsigned int index );
 /**
  * Locate ACPI root system description table
  *
- * @ret rsdt		ACPI root system description table, or UNULL
+ * @ret rsdt		ACPI root system description table, or NULL
  */
-userptr_t acpi_find_rsdt ( void );
+const struct acpi_rsdt * acpi_find_rsdt ( void );
 
 /**
  * Locate ACPI table
  *
  * @v signature		Requested table signature
  * @v index		Requested index of table with this signature
- * @ret table		Table, or UNULL if not found
+ * @ret table		Table, or NULL if not found
  */
-userptr_t acpi_find ( uint32_t signature, unsigned int index );
+const struct acpi_header * acpi_find ( uint32_t signature,
+				       unsigned int index );
 
 extern struct acpi_descriptor *
 acpi_describe ( struct interface *interface );
 #define acpi_describe_TYPE( object_type )				\
 	typeof ( struct acpi_descriptor * ( object_type ) )
 
-extern userptr_t ( * acpi_finder ) ( uint32_t signature, unsigned int index );
+extern const struct acpi_header * ( * acpi_finder ) ( uint32_t signature,
+						      unsigned int index );
 
 extern void acpi_fix_checksum ( struct acpi_header *acpi );
-extern userptr_t acpi_table ( uint32_t signature, unsigned int index );
+extern const struct acpi_header * acpi_table ( uint32_t signature,
+					       unsigned int index );
 extern int acpi_extract ( uint32_t signature, void *data,
-			  int ( * extract ) ( userptr_t zsdt, size_t len,
-					      size_t offset, void *data ) );
+			  int ( * extract ) ( const struct acpi_header *zsdt,
+					      size_t len, size_t offset,
+					      void *data ) );
 extern void acpi_add ( struct acpi_descriptor *desc );
 extern void acpi_del ( struct acpi_descriptor *desc );
 extern int acpi_install ( int ( * install ) ( struct acpi_header *acpi ) );

src/include/ipxe/efi/efi_acpi.h

@@ -20,9 +20,9 @@ FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
  *
  * @v signature		Requested table signature
  * @v index		Requested index of table with this signature
- * @ret table		Table, or UNULL if not found
+ * @ret table		Table, or NULL if not found
  */
-static inline __attribute__ (( always_inline )) userptr_t
+static inline __attribute__ (( always_inline )) const struct acpi_header *
 ACPI_INLINE ( efi, acpi_find ) ( uint32_t signature, unsigned int index ) {
 
 	return acpi_find_via_rsdt ( signature, index );

src/include/ipxe/null_acpi.h

@@ -9,17 +9,19 @@
 
 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 
+#include <stddef.h>
+
 #ifdef ACPI_NULL
 #define ACPI_PREFIX_null
 #else
 #define ACPI_PREFIX_null __null_
 #endif
 
-static inline __attribute__ (( always_inline )) userptr_t
+static inline __attribute__ (( always_inline )) const struct acpi_header *
 ACPI_INLINE ( null, acpi_find ) ( uint32_t signature __unused,
 				  unsigned int index __unused ) {
 
-	return UNULL;
+	return NULL;
 }
 
 #endif /* _IPXE_NULL_ACPI_H */

src/interface/efi/efi_acpi.c

@@ -31,6 +31,7 @@ FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
  */
 
 #include <ipxe/acpi.h>
+#include <ipxe/uaccess.h>
 #include <ipxe/efi/efi.h>
 #include <ipxe/efi/Guid/Acpi.h>
 #include <ipxe/efi/efi_acpi.h>
@@ -42,15 +43,15 @@ EFI_USE_TABLE ( ACPI_10_TABLE, &rsdp, 0 );
 /**
  * Locate ACPI root system description table
  *
- * @ret rsdt		ACPI root system description table, or UNULL
+ * @ret rsdt		ACPI root system description table, or NULL
  */
-static userptr_t efi_find_rsdt ( void ) {
+static const struct acpi_rsdt * efi_find_rsdt ( void ) {
 
 	/* Locate RSDT via ACPI configuration table, if available */
 	if ( rsdp )
 		return phys_to_virt ( rsdp->RsdtAddress );
 
-	return UNULL;
+	return NULL;
 }
 
 PROVIDE_ACPI ( efi, acpi_find_rsdt, efi_find_rsdt );

src/interface/linux/linux_acpi.c

@@ -42,7 +42,7 @@ struct linux_acpi_table {
 	/** Index */
 	unsigned int index;
 	/** Cached data */
-	userptr_t data;
+	void *data;
 };
 
 /** List of cached ACPI tables */
@@ -53,9 +53,10 @@ static LIST_HEAD ( linux_acpi_tables );
  *
  * @v signature		Requested table signature
  * @v index		Requested index of table with this signature
- * @ret table		Table, or UNULL if not found
+ * @ret table		Table, or NULL if not found
  */
-static userptr_t linux_acpi_find ( uint32_t signature, unsigned int index ) {
+static const struct acpi_header * linux_acpi_find ( uint32_t signature,
+						    unsigned int index ) {
 	struct linux_acpi_table *table;
 	struct acpi_header *header;
 	union {
@@ -121,7 +122,7 @@ static userptr_t linux_acpi_find ( uint32_t signature, unsigned int index ) {
  err_read:
 	free ( table );
  err_alloc:
-	return UNULL;
+	return NULL;
 }
 
 /**

src/tests/acpi_test.c

@@ -32,6 +32,7 @@ FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 /* Forcibly enable assertions */
 #undef NDEBUG
 
+#include <string.h>
 #include <ipxe/acpi.h>
 #include <ipxe/acpimac.h>
 #include <ipxe/if_ether.h>
@@ -185,26 +186,27 @@ static struct acpi_test_tables *acpi_test_tables;
  *
  * @v signature		Requested table signature
  * @v index		Requested index of table with this signature
- * @ret table		Table, or UNULL if not found
+ * @ret table		Table, or NULL if not found
  */
-static userptr_t acpi_test_find ( uint32_t signature, unsigned int index ) {
+static const struct acpi_header * acpi_test_find ( uint32_t signature,
+						   unsigned int index ) {
 	struct acpi_test_table *table;
 	unsigned int i;
 
 	/* Fail if no test tables are installed */
 	if ( ! acpi_test_tables )
-		return UNULL;
+		return NULL;
 
 	/* Scan through test tables */
 	for ( i = 0 ; i < acpi_test_tables->count ; i++ ) {
 		table = acpi_test_tables->table[i];
 		if ( ( signature == le32_to_cpu ( table->signature.raw ) ) &&
 		     ( index-- == 0 ) ) {
-			return virt_to_user ( table->data );
+			return table->data;
 		}
 	}
 
-	return UNULL;
+	return NULL;
 }
 
 /** Override ACPI table finder */