[PATCH] libata: First cut at verifying and validating all the id checks.

[PATCH] libata: First cut at verifying and validating all the id checks.

[Alan Cox]

- Fix those which require a word is checked for validity
- Note limits on version information with ancient ATA
- Correct EIDE dword_io check ready for adding 32bit PIO

Signed-off-by: Alan Cox <alan@redhat.com>

diff -u --new-file --recursive --exclude-from /usr/src/exclude linux.vanilla-2.6.23rc1-mm1/include/linux/ata.h linux-2.6.23rc1-mm1/include/linux/ata.h
--- linux.vanilla-2.6.23rc1-mm1/include/linux/ata.h	2007-07-26 15:02:58.000000000 +0100
+++ linux-2.6.23rc1-mm1/include/linux/ata.h	2007-08-07 22:29:05.000000000 +0100
@@ -334,27 +335,17 @@
 };
 
 #define ata_id_is_ata(id)	(((id)[0] & (1 << 15)) == 0)
-#define ata_id_rahead_enabled(id) ((id)[85] & (1 << 6))
-#define ata_id_wcache_enabled(id) ((id)[85] & (1 << 5))
-#define ata_id_hpa_enabled(id)	((id)[85] & (1 << 10))
-#define ata_id_has_fua(id)	((id)[84] & (1 << 6))
-#define ata_id_has_flush(id)	((id)[83] & (1 << 12))
-#define ata_id_has_flush_ext(id) ((id)[83] & (1 << 13))
-#define ata_id_has_lba48(id)	((id)[83] & (1 << 10))
-#define ata_id_has_hpa(id)	((id)[82] & (1 << 10))
-#define ata_id_has_wcache(id)	((id)[82] & (1 << 5))
-#define ata_id_has_pm(id)	((id)[82] & (1 << 3))
-#define ata_id_has_lba(id)	((id)[49] & (1 << 9))
-#define ata_id_has_dma(id)	((id)[49] & (1 << 8))
 #define ata_id_has_ncq(id)	((id)[76] & (1 << 8))
 #define ata_id_queue_depth(id)	(((id)[75] & 0x1f) + 1)
 #define ata_id_removeable(id)	((id)[0] & (1 << 7))
-#define ata_id_has_dword_io(id)	((id)[50] & (1 << 0))
+#define ata_id_has_dword_io(id)	((id)[48] & (1 << 0))
+#define ata_id_iordy_disable(id) ((id)[49] & (1 << 10))
+#define ata_id_has_iordy(id)     ((id)[49] & (1 << 11))
+#define ata_id_has_lba(id)	((id)[49] & (1 << 9))
+#define ata_id_has_dma(id)	((id)[49] & (1 << 8))
 #define ata_id_has_AN(id)	\
 	( (((id)[76] != 0x0000) && ((id)[76] != 0xffff)) && \
 	  ((id)[78] & (1 << 5)) )
-#define ata_id_iordy_disable(id) ((id)[49] & (1 << 10))
-#define ata_id_has_iordy(id) ((id)[49] & (1 << 9))
 #define ata_id_u32(id,n)	\
 	(((u32) (id)[(n) + 1] << 16) | ((u32) (id)[(n)]))
 #define ata_id_u64(id,n)	\
@@ -367,6 +358,90 @@
 #define ata_id_has_hipm(id)	((id)[76] & (1 << 9))
 #define ata_id_has_dipm(id)	((id)[78] & (1 << 3))
 
+static inline int ata_id_has_fua(const u16 *id)
+{
+	if ((id[84] & 0xC000) != 0x4000)
+		return 0;
+	return id[84] & (1 << 6);
+}
+
+static inline int ata_id_has_flush(const u16 *id)
+{
+	if ((id[83] & 0xC000) != 0x4000)
+		return 0;
+	return id[83] & (1 << 12);
+}
+
+static inline int ata_id_has_flush_ext(const u16 *id)
+{
+	if ((id[83] & 0xC000) != 0x4000)
+		return 0;
+	return id[83] & (1 << 13);
+}
+
+static inline int ata_id_has_lba48(const u16 *id)
+{
+	if ((id[83] & 0xC000) != 0x4000)
+		return 0;
+	return id[83] & (1 << 10);
+}
+
+static inline int ata_id_hpa_enabled(const u16 *id)
+{
+	/* Yes children, word 83 valid bits cover word 82 data */
+	if ((id[83] & 0xC000) != 0x4000)
+		return 0;
+	/* And 87 covers 85-87 */
+	if ((id[87] & 0xC000) != 0x4000)
+		return 0;
+	/* Check command sets enabled as well as supported */
+	if ((id[85] & ( 1 << 10)) == 0)
+		return 0;
+	return id[82] & (1 << 10);
+}
+
+static inline int ata_id_has_wcache(const u16 *id)
+{
+	/* Yes children, word 83 valid bits cover word 82 data */
+	if ((id[83] & 0xC000) != 0x4000)
+		return 0;
+	return id[82] & (1 << 5);
+}
+
+static inline int ata_id_has_pm(const u16 *id)
+{
+	if ((id[83] & 0xC000) != 0x4000)
+		return 0;
+	return id[82] & (1 << 3);
+}
+
+static inline int ata_id_rahead_enabled(const u16 *id)
+{
+	if ((id[87] & 0xC000) != 0x4000)
+		return 0;
+	return id[85] & (1 << 6);
+}
+
+static inline int ata_id_wcache_enabled(const u16 *id)
+{
+	if ((id[87] & 0xC000) != 0x4000)
+		return 0;
+	return id[85] & (1 << 5);
+}
+
+/**
+ *	ata_id_major_version	-	get ATA level of drive
+ *	@id: Identify data
+ *
+ *	Caveats:
+ *		ATA-1 considers identify optional
+ *		ATA-2 introduces mandatory identify
+ *		ATA-3 introduces word 80 and accurate reporting
+ *
+ *	The practical impact of this is that ata_id_major_version cannot
+ *	reliably report on drives below ATA3. 
+ */
+
 static inline unsigned int ata_id_major_version(const u16 *id)
 {
 	unsigned int mver;

Re: [PATCH] libata: First cut at verifying and validating all the id checks.

[Jeff Garzik]

Alan Cox wrote:
> - Fix those which require a word is checked for validity
> - Note limits on version information with ancient ATA
> - Correct EIDE dword_io check ready for adding 32bit PIO
> 
> Signed-off-by: Alan Cox <alan@redhat.com>

any update on this?

I definitely agree we should be checking the validity values.

	Jeff

Re: [PATCH] libata: First cut at verifying and validating all the id checks.

[Alan Cox]

On Thu, 20 Sep 2007 16:55:37 -0400
Jeff Garzik <jeff@garzik.org> wrote:

> Alan Cox wrote:
> > - Fix those which require a word is checked for validity
> > - Note limits on version information with ancient ATA
> > - Correct EIDE dword_io check ready for adding 32bit PIO
> > 
> > Signed-off-by: Alan Cox <alan@redhat.com>
> 
> any update on this?

Its sitting in -mm and I've heard no screaming so far