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usb_storage: fix ehci driver max transfer size

PATCH New Stefan Herbrechtsmeier 4 participants 23 messages Jun 18, 2012 – Jul 18, 2012

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#0 lore raw

PATCH 1/1 usb_storage: fix ehci driver max transfer size

The commit 5dd95cf93dfffa1d19a1928990852aac9f55b9d9 'usb_storage:
Fix EHCI "out of buffer pointers" with CD-ROM' introduce a bug in usb_storage as it wrongly assumes that every transfer can use 4k per qt_buffer. This is wrong if the start address of the data is not 4k aligned and leads to 'EHCI timed out on TD' messages because of 'out of buffer pointers' in ehci_td_buffer function.

---
 common/usb_storage.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)
common/usb_storage.c +3 -3
index faad237..612a553 100644
@@ -1416,10 +1416,10 @@ int usb_stor_get_info(struct usb_device *dev, struct us_data *ss,
 	USB_STOR_PRINTF("partype: %d\n", dev_desc->part_type);
 
 	/*
-	 * The U-Boot EHCI driver cannot handle more than 4096 * 5 bytes in a
-	 * transfer without running itself out of qt_buffers.
+	 * The U-Boot EHCI driver cannot handle more than 4096 * 4 bytes in a
+	 * unaligned transfer without running itself out of qt_buffers.
 	 */
-	ss->max_xfer_blk = (4096 * 5) / dev_desc->blksz;
+	ss->max_xfer_blk = (4096 * 4) / dev_desc->blksz;
 
 	init_part(dev_desc);
 
Signature · 1 line
1.7.9.5
#1 lore raw

PATCH 1/1 usb_storage: fix ehci driver max transfer size

Dear Stefan Herbrechtsmeier,

Quoted 6 lines

The commit 5dd95cf93dfffa1d19a1928990852aac9f55b9d9 'usb_storage:
Fix EHCI "out of buffer pointers" with CD-ROM' introduce a bug in usb_storage as it wrongly assumes that every transfer can use 4k per qt_buffer. This is wrong if the start address of the data is not 4k aligned and leads to 'EHCI timed out on TD' messages because of 'out of buffer pointers' in ehci_td_buffer function.

Stefan, thanks a lot for finding this! I'll look into it on 21st I hope.

Quoted 14 lines
---
 common/usb_storage.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)
common/usb_storage.c +0 -0
index faad237..612a553 100644
@@ -1416,10 +1416,10 @@ int usb_stor_get_info(struct usb_device *dev,
 struct us_data *ss, USB_STOR_PRINTF("partype: %d\n", dev_desc->part_type);
 

common/usb_storage.c int usb_stor_get_info(struct usb_device *dev, · line 1424

Quoted 10 lines
common/usb_storage.c +3 -3
 	/*
-	 * The U-Boot EHCI driver cannot handle more than 4096 * 5 bytes in a
-	 * transfer without running itself out of qt_buffers.
+	 * The U-Boot EHCI driver cannot handle more than 4096 * 4 bytes in a
+	 * unaligned transfer without running itself out of qt_buffers.
 	 */
-	ss->max_xfer_blk = (4096 * 5) / dev_desc->blksz;
+	ss->max_xfer_blk = (4096 * 4) / dev_desc->blksz;
 
 	init_part(dev_desc);

Best regards,
Marek Vasut

#2 lore raw

PATCH 1/1 usb_storage: fix ehci driver max transfer size

In reply to Stefan Herbrechtsmeier

Dear Stefan Herbrechtsmeier,

Quoted 9 lines

The commit 5dd95cf93dfffa1d19a1928990852aac9f55b9d9 'usb_storage:
Fix EHCI "out of buffer pointers" with CD-ROM' introduce a bug in usb_storage as it wrongly assumes that every transfer can use 4k per qt_buffer. This is wrong if the start address of the data is not 4k aligned and leads to 'EHCI timed out on TD' messages because of 'out of buffer pointers' in ehci_td_buffer function.

Ok, first I have to admit I broke my promise to look into this ASAP, sorry about it :-(

Just curious, but shouldn't it be ((4096 * 5) / dev_desc->blk_sz) - 1 ?

Quoted 11 lines
---
 common/usb_storage.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)
common/usb_storage.c +0 -0
index faad237..612a553 100644
@@ -1416,10 +1416,10 @@ int usb_stor_get_info(struct usb_device *dev,
 struct us_data *ss, USB_STOR_PRINTF("partype: %d\n", dev_desc->part_type);
 

common/usb_storage.c int usb_stor_get_info(struct usb_device *dev, · line 1424

Quoted 10 lines
common/usb_storage.c +3 -3
 	/*
-	 * The U-Boot EHCI driver cannot handle more than 4096 * 5 bytes in a
-	 * transfer without running itself out of qt_buffers.
+	 * The U-Boot EHCI driver cannot handle more than 4096 * 4 bytes in a
+	 * unaligned transfer without running itself out of qt_buffers.
 	 */
-	ss->max_xfer_blk = (4096 * 5) / dev_desc->blksz;
+	ss->max_xfer_blk = (4096 * 4) / dev_desc->blksz;
 
 	init_part(dev_desc);

Best regards,
Marek Vasut

#3 lore raw

PATCH 1/1 usb_storage: fix ehci driver max transfer size

Am 03.07.2012 20:10, schrieb Marek Vasut:

Quoted 11 lines
Quoted 9 lines

The commit 5dd95cf93dfffa1d19a1928990852aac9f55b9d9 'usb_storage:
Fix EHCI "out of buffer pointers" with CD-ROM' introduce a bug in usb_storage as it wrongly assumes that every transfer can use 4k per qt_buffer. This is wrong if the start address of the data is not 4k aligned and leads to 'EHCI timed out on TD' messages because of 'out of buffer pointers' in ehci_td_buffer function.

Ok, first I have to admit I broke my promise to look into this ASAP, sorry about it :-(

No problem, as long as we get it into the next release. ;-)

Quoted 2 lines

Just curious, but shouldn't it be ((4096 * 5) / dev_desc->blk_sz) - 1 ?

No, because the first blk need to be aligned with the 4096. In worst case the blk is at the end of the 4096 range. If we assume that the blk is aligned to blk_sz we can change it to ((4096 * 4) / dev_desc->blk_sz)
+ 1. I skip the last blk (+ 1) because with 4096 aligned first blk we unaligned the next transfer and add extra short packages to each ehci transfer.

If we want to maximise the usage we need to calculate the max_xfer_blk depending on the start address of the first blk.

Quoted 22 lines
Quoted 21 lines
---
  common/usb_storage.c |    6 +++---
  1 file changed, 3 insertions(+), 3 deletions(-)
common/usb_storage.c +3 -3
index faad237..612a553 100644
@@ -1416,10 +1416,10 @@ int usb_stor_get_info(struct usb_device *dev,
 struct us_data *ss, USB_STOR_PRINTF("partype: %d\n", dev_desc->part_type);
 
  	/*
-	 * The U-Boot EHCI driver cannot handle more than 4096 * 5 bytes in a
-	 * transfer without running itself out of qt_buffers.
+	 * The U-Boot EHCI driver cannot handle more than 4096 * 4 bytes in a
+	 * unaligned transfer without running itself out of qt_buffers.
  	 */
-	ss->max_xfer_blk = (4096 * 5) / dev_desc->blksz;
+	ss->max_xfer_blk = (4096 * 4) / dev_desc->blksz;
 
  	init_part(dev_desc);
#4 lore raw

PATCH 1/1 usb_storage: fix ehci driver max transfer size

Quoted 24 lines

Am 03.07.2012 20:10, schrieb Marek Vasut:

Quoted 10 lines
Quoted 9 lines

The commit 5dd95cf93dfffa1d19a1928990852aac9f55b9d9 'usb_storage:
Fix EHCI "out of buffer pointers" with CD-ROM' introduce a bug in usb_storage as it wrongly assumes that every transfer can use 4k per qt_buffer. This is wrong if the start address of the data is not 4k aligned and leads to 'EHCI timed out on TD' messages because of 'out of buffer pointers' in ehci_td_buffer function.

Ok, first I have to admit I broke my promise to look into this ASAP, sorry

about

Quoted 1 line

it :-(

No problem, as long as we get it into the next release. ;-)

Quoted 2 lines

Just curious, but shouldn't it be ((4096 * 5) / dev_desc->blk_sz) - 1 ?

No, because the first blk need to be aligned with the 4096. In worst case the blk is at the end of the 4096 range. If we assume that the blk is aligned to blk_sz we can change it to ((4096 * 4) / dev_desc->blk_sz)
+ 1. I skip the last blk (+ 1) because with 4096 aligned first blk we unaligned the next transfer and add extra short packages to each ehci transfer.

Quoted 3 lines

If we want to maximise the usage we need to calculate the max_xfer_blk depending on the start address of the first blk.

I admit to not totally getting it. However, there are two things that come to my mind:
- Doesn't the EHCI Specification mention exactly five buffers that can/should/must
be used?
- I think I once stumbled across some comment that said as much as the blocks
always having to be aligned anyway?

:-) Kolja

Quoted 31 lines
Quoted 9 lines

common/usb_storage.c int usb_stor_get_info(struct usb_device

Quoted 9 lines
---
  common/usb_storage.c |    6 +++---
  1 file changed, 3 insertions(+), 3 deletions(-)
common/usb_storage.c +0 -0
index faad237..612a553 100644
@@ -1416,10 +1416,10 @@ int usb_stor_get_info(struct usb_device

*dev,

Quoted 5 lines
Quoted 1 line

struct us_data *ss, USB_STOR_PRINTF("partype: %d\n", dev_desc-

part_type);

common/usb_storage.c

Quoted 3 lines

/*

common/usb_storage.c +0 -1
-	 * The U-Boot EHCI driver cannot handle more than 4096 * 5 bytes in

a

Quoted 2 lines

common/usb_storage.c

Quoted 2 lines
common/usb_storage.c +1 -1
-	 * transfer without running itself out of qt_buffers.
+	 * The U-Boot EHCI driver cannot handle more than 4096 * 4 bytes in

a

Quoted 7 lines

common/usb_storage.c int usb_stor_get_info(struct usb_device *dev, struct us_data *ss, · line 1424

Quoted 6 lines
common/usb_storage.c +2 -1
+	 * unaligned transfer without running itself out of qt_buffers.
  	 */
-	ss->max_xfer_blk = (4096 * 5) / dev_desc->blksz;
+	ss->max_xfer_blk = (4096 * 4) / dev_desc->blksz;
 
  	init_part(dev_desc);

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#5 lore raw

PATCH 1/1 usb_storage: fix ehci driver max transfer size

Am 04.07.2012 08:57, schrieb Schneider, Kolja:

Quoted 22 lines
Quoted 22 lines

Am 03.07.2012 20:10, schrieb Marek Vasut:

Quoted 10 lines
Quoted 9 lines

The commit 5dd95cf93dfffa1d19a1928990852aac9f55b9d9 'usb_storage:
Fix EHCI "out of buffer pointers" with CD-ROM' introduce a bug in usb_storage as it wrongly assumes that every transfer can use 4k per qt_buffer. This is wrong if the start address of the data is not 4k aligned and leads to 'EHCI timed out on TD' messages because of 'out of buffer pointers' in ehci_td_buffer function.

Ok, first I have to admit I broke my promise to look into this ASAP, sorry

about

Quoted 1 line

it :-(

No problem, as long as we get it into the next release. ;-)

Quoted 1 line

Just curious, but shouldn't it be ((4096 * 5) / dev_desc->blk_sz) - 1 ?

No, because the first blk need to be aligned with the 4096. In worst case the blk is at the end of the 4096 range. If we assume that the blk is aligned to blk_sz we can change it to ((4096 * 4) / dev_desc->blk_sz)
+ 1. I skip the last blk (+ 1) because with 4096 aligned first blk we unaligned the next transfer and add extra short packages to each ehci transfer.

Quoted 6 lines
Quoted 3 lines

If we want to maximise the usage we need to calculate the max_xfer_blk depending on the start address of the first blk.

I admit to not totally getting it. However, there are two things that come to my mind:
- Doesn't the EHCI Specification mention exactly five buffers that can/should/must
be used?

Yes, you can use up to five 4096 byte buffers.

Quoted 2 lines

- I think I once stumbled across some comment that said as much as the blocks
always having to be aligned anyway?

The buffers must be aligned to a 4096 byte page. This means that you have to use the first and last buffer to align your data to the next or previous 4096 byte page boundary.

#6 lore raw

PATCH 1/1 usb_storage: fix ehci driver max transfer size

Dear Stefan Herbrechtsmeier,

Quoted 34 lines

Am 04.07.2012 08:57, schrieb Schneider, Kolja:

Quoted 33 lines
Quoted 29 lines

Am 03.07.2012 20:10, schrieb Marek Vasut:

Quoted 7 lines
Quoted 7 lines

The commit 5dd95cf93dfffa1d19a1928990852aac9f55b9d9 'usb_storage:
Fix EHCI "out of buffer pointers" with CD-ROM' introduce a bug in usb_storage as it wrongly assumes that every transfer can use 4k per qt_buffer. This is wrong if the start address of the data is not 4k aligned and leads to 'EHCI timed out on TD' messages because of 'out of buffer pointers' in ehci_td_buffer function.

Quoted 5 lines
Quoted 2 lines

Ok, first I have to admit I broke my promise to look into this ASAP, sorry

about

Quoted 1 line

it :-(

No problem, as long as we get it into the next release. ;-)

Quoted 1 line

Just curious, but shouldn't it be ((4096 * 5) / dev_desc->blk_sz) - 1 ?

No, because the first blk need to be aligned with the 4096. In worst case the blk is at the end of the 4096 range. If we assume that the blk is aligned to blk_sz we can change it to ((4096 * 4) / dev_desc->blk_sz)
+ 1. I skip the last blk (+ 1) because with 4096 aligned first blk we unaligned the next transfer and add extra short packages to each ehci transfer.

Quoted 2 lines

If we want to maximise the usage we need to calculate the max_xfer_blk depending on the start address of the first blk.

I admit to not totally getting it. However, there are two things that come

to my mind:

Quoted 8 lines
Quoted 4 lines

- Doesn't the EHCI Specification mention exactly five buffers that
can/should/must

be used?

Yes, you can use up to five 4096 byte buffers.

Quoted 1 line

- I think I once stumbled across some comment that said as much as

the

Quoted 7 lines
Quoted 3 lines

blocks

always having to be aligned anyway?

The buffers must be aligned to a 4096 byte page. This means that you have to use the first and last buffer to align your data to the next or previous 4096 byte page boundary.

All right, I managed to replicate the issue. This (or similar) doesn't work for you, right:

usb read 0x42000004 0x0 0x400

The proper solution would be to introduce a bounce buffer for such unaligned transfers. A proper, generic bounce buffer that can be configured to bounce on specified boundaries and warns about performance penalties.

Best regards,
Marek Vasut

#7 lore raw

PATCH 1/1 usb_storage: fix ehci driver max transfer size

Am 07.07.2012 23:58, schrieb Marek Vasut:

Quoted 40 lines
Quoted 29 lines

Am 04.07.2012 08:57, schrieb Schneider, Kolja:

Quoted 28 lines
Quoted 25 lines

Am 03.07.2012 20:10, schrieb Marek Vasut:

Quoted 11 lines
Quoted 9 lines

The commit 5dd95cf93dfffa1d19a1928990852aac9f55b9d9 'usb_storage:
Fix EHCI "out of buffer pointers" with CD-ROM' introduce a bug in usb_storage as it wrongly assumes that every transfer can use 4k per qt_buffer. This is wrong if the start address of the data is not 4k aligned and leads to 'EHCI timed out on TD' messages because of 'out of buffer pointers' in ehci_td_buffer function.

Ok, first I have to admit I broke my promise to look into this ASAP, sorry

about

Quoted 1 line

it :-(

No problem, as long as we get it into the next release. ;-)

Quoted 1 line

Just curious, but shouldn't it be ((4096 * 5) / dev_desc->blk_sz) - 1 ?

No, because the first blk need to be aligned with the 4096. In worst case the blk is at the end of the 4096 range. If we assume that the blk is aligned to blk_sz we can change it to ((4096 * 4) / dev_desc->blk_sz)
+ 1. I skip the last blk (+ 1) because with 4096 aligned first blk we unaligned the next transfer and add extra short packages to each ehci transfer.

Quoted 2 lines

If we want to maximise the usage we need to calculate the max_xfer_blk depending on the start address of the first blk.

I admit to not totally getting it. However, there are two things that come

to my mind:

Quoted 7 lines
Quoted 4 lines

- Doesn't the EHCI Specification mention exactly five buffers that
can/should/must

be used?

Yes, you can use up to five 4096 byte buffers.

Quoted 1 line

- I think I once stumbled across some comment that said as much as

the

Quoted 2 lines
Quoted 2 lines

blocks

Quoted 8 lines
Quoted 4 lines
Quoted 1 line

always having to be aligned anyway?

The buffers must be aligned to a 4096 byte page. This means that you have to use the first and last buffer to align your data to the next or previous 4096 byte page boundary.

All right, I managed to replicate the issue. This (or similar) doesn't work for you, right:

usb read 0x42000004 0x0 0x400

I observe the bug during
fatload usb 0 0x800000 uImage

...
dev=0ffb0440, pipe=c8008283, buffer=00a90000, length=20480, req=(null)
...
dev=0ffb0440, pipe=c8008283, buffer=00a95000, length=20480, req=(null)
...
dev=0ffb0440, pipe=c8008283, buffer=00a9a000, length=18432, req=(null)
...
dev=0ffb0440, pipe=c8008283, buffer=00a9e800, length=20480, req=(null) out of buffer pointers (2048 bytes left)
...

It looks like the file is fragmented. During load the start address becomes unaligned and thereby the code wrongly tries to transfer more blocks than possible.

Before the above mentioned patch the max_xfer_blk was much smaller (20), so that the problem never appears.

Quoted 3 lines

The proper solution would be to introduce a bounce buffer for such unaligned transfers. A proper, generic bounce buffer that can be configured to bounce on specified boundaries and warns about performance penalties.

Why not limit the max_xfer_blk to the maximum save count [(4096 * 4) / dev_desc->blksz)] or calculate the max_xfer_blk depending on the start address of the transfer:

max_xfer_blk = ((4096 * 5) - (start & ~4096) / dev_desc->blksz

Regards,
Stefan

#8 lore raw

PATCH 1/1 usb_storage: fix ehci driver max transfer size

Dear Stefan Herbrechtsmeier,

Quoted 89 lines

Am 07.07.2012 23:58, schrieb Marek Vasut:

Quoted 53 lines
Quoted 36 lines

Am 04.07.2012 08:57, schrieb Schneider, Kolja:

Quoted 35 lines
Quoted 30 lines

Am 03.07.2012 20:10, schrieb Marek Vasut:

Quoted 7 lines
Quoted 7 lines

The commit 5dd95cf93dfffa1d19a1928990852aac9f55b9d9 'usb_storage:
Fix EHCI "out of buffer pointers" with CD-ROM' introduce a bug in usb_storage as it wrongly assumes that every transfer can use 4k per qt_buffer. This is wrong if the start address of the data is not 4k aligned and leads to 'EHCI timed out on TD' messages because of 'out of buffer pointers' in ehci_td_buffer function.

Quoted 5 lines
Quoted 2 lines

Ok, first I have to admit I broke my promise to look into this ASAP, sorry

about

Quoted 1 line

it :-(

No problem, as long as we get it into the next release. ;-)

Quoted 2 lines

Just curious, but shouldn't it be ((4096 * 5) / dev_desc->blk_sz) - 1 ?

No, because the first blk need to be aligned with the 4096. In worst case the blk is at the end of the 4096 range. If we assume that the blk is aligned to blk_sz we can change it to ((4096 * 4) / dev_desc->blk_sz) + 1. I skip the last blk (+ 1) because with 4096 aligned first blk we unaligned the next transfer and add extra short packages to each ehci transfer.

Quoted 2 lines

If we want to maximise the usage we need to calculate the max_xfer_blk depending on the start address of the first blk.

I admit to not totally getting it. However, there are two things that come

to my mind:

Quoted 8 lines
Quoted 4 lines

- Doesn't the EHCI Specification mention exactly five buffers that
can/should/must

be used?

Yes, you can use up to five 4096 byte buffers.

Quoted 1 line

- I think I once stumbled across some comment that said as much as

the

Quoted 4 lines
Quoted 3 lines

blocks

always having to be aligned anyway?

Quoted 8 lines
Quoted 3 lines

The buffers must be aligned to a 4096 byte page. This means that you have to use the first and last buffer to align your data to the next or previous 4096 byte page boundary.

All right, I managed to replicate the issue. This (or similar) doesn't work for you, right:

usb read 0x42000004 0x0 0x400

I observe the bug during
fatload usb 0 0x800000 uImage

...
dev=0ffb0440, pipe=c8008283, buffer=00a90000, length=20480, req=(null)
...
dev=0ffb0440, pipe=c8008283, buffer=00a95000, length=20480, req=(null)
...
dev=0ffb0440, pipe=c8008283, buffer=00a9a000, length=18432, req=(null)
...
dev=0ffb0440, pipe=c8008283, buffer=00a9e800, length=20480, req=(null) out of buffer pointers (2048 bytes left)
...

It looks like the file is fragmented. During load the start address becomes unaligned and thereby the code wrongly tries to transfer more blocks than possible.

Before the above mentioned patch the max_xfer_blk was much smaller (20), so that the problem never appears.

Quoted 4 lines

The proper solution would be to introduce a bounce buffer for such unaligned transfers. A proper, generic bounce buffer that can be configured to bounce on specified boundaries and warns about performance penalties.

Quoted 5 lines

Why not limit the max_xfer_blk to the maximum save count [(4096 * 4) / dev_desc->blksz)] or calculate the max_xfer_blk depending on the start address of the transfer:

max_xfer_blk = ((4096 * 5) - (start & ~4096) / dev_desc->blksz

This looks like a much better solution ;-) Can you redo the patch for that? Also, there's some macro for that rounding in include/common.h

Quoted 3 lines

Regards,
Stefan

Best regards,
Marek Vasut

#9 lore raw

PATCH v2 1/1 usb_storage: fix ehci driver max transfer size

In reply to Stefan Herbrechtsmeier

The commit 5dd95cf93dfffa1d19a1928990852aac9f55b9d9 'usb_storage:
Fix EHCI "out of buffer pointers" with CD-ROM' introduce a bug in usb_storage as it wrongly assumes that every transfer can use 4096 bytes per qt_buffer. This is wrong if the start address of the data is not page aligned to 4096 bytes and leads to 'EHCI timed out on TD' messages because of 'out of buffer pointers' in ehci_td_buffer function.

The bug appears during load of a fragmented file and read from or write to an unaligned memory address.

---
Changes for v2:
- Replace fixed worst case calculation with dynamic computation based on start address of transfer

 common/usb_storage.c |   37 ++++++++++++++++++++-----------------
 1 file changed, 20 insertions(+), 17 deletions(-)
common/usb_storage.c +20 -17
index faad237..bdc306f 100644
@@ -150,12 +150,17 @@ struct us_data {
 	unsigned int	irqpipe;	 	/* pipe for release_irq */
 	unsigned char	irqmaxp;		/* max packed for irq Pipe */
 	unsigned char	irqinterval;		/* Intervall for IRQ Pipe */
-	unsigned long	max_xfer_blk;		/* Max blocks per xfer */
 	ccb		*srb;			/* current srb */
 	trans_reset	transport_reset;	/* reset routine */
 	trans_cmnd	transport;		/* transport routine */
 };
 
+/*
+ * The U-Boot EHCI driver cannot handle more than 5 page aligned buffers
+ * of 4096 bytes in a transfer without running itself out of qt_buffers
+ */
+#define USB_MAX_XFER_BLK(start, blksz)	(((4096 * 5) - (start % 4096)) / blksz)
+
 static struct us_data usb_stor[USB_MAX_STOR_DEV];
 
 
@@ -1041,7 +1046,7 @@ static void usb_bin_fixup(struct usb_device_descriptor descriptor,
 unsigned long usb_stor_read(int device, unsigned long blknr,
 			    unsigned long blkcnt, void *buffer)
 {
-	unsigned long start, blks, buf_addr;
+	unsigned long start, blks, buf_addr, max_xfer_blk;
 	unsigned short smallblks;
 	struct usb_device *dev;
 	struct us_data *ss;
@@ -1083,12 +1088,14 @@ unsigned long usb_stor_read(int device, unsigned long blknr,
 		/* XXX need some comment here */
 		retry = 2;
 		srb->pdata = (unsigned char *)buf_addr;
-		if (blks > ss->max_xfer_blk)
-			smallblks = ss->max_xfer_blk;
+		max_xfer_blk = USB_MAX_XFER_BLK(buf_addr,
+						usb_dev_desc[device].blksz);
+		if (blks > max_xfer_blk)
+			smallblks = (unsigned short) max_xfer_blk;
 		else
 			smallblks = (unsigned short) blks;
 retry_it:
-		if (smallblks == ss->max_xfer_blk)
+		if (smallblks == max_xfer_blk)
 			usb_show_progress();
 		srb->datalen = usb_dev_desc[device].blksz * smallblks;
 		srb->pdata = (unsigned char *)buf_addr;
@@ -1109,7 +1116,7 @@ retry_it:
 			start, smallblks, buf_addr);
 
 	usb_disable_asynch(0); /* asynch transfer allowed */
-	if (blkcnt >= ss->max_xfer_blk)
+	if (blkcnt >= max_xfer_blk)
 		debug("\n");
 	return blkcnt;
 }
@@ -1117,7 +1124,7 @@ retry_it:
 unsigned long usb_stor_write(int device, unsigned long blknr,
 				unsigned long blkcnt, const void *buffer)
 {
-	unsigned long start, blks, buf_addr;
+	unsigned long start, blks, buf_addr, max_xfer_blk;
 	unsigned short smallblks;
 	struct usb_device *dev;
 	struct us_data *ss;
@@ -1162,12 +1169,14 @@ unsigned long usb_stor_write(int device, unsigned long blknr,
 		 */
 		retry = 2;
 		srb->pdata = (unsigned char *)buf_addr;
-		if (blks > ss->max_xfer_blk)
-			smallblks = ss->max_xfer_blk;
+		max_xfer_blk = USB_MAX_XFER_BLK(buf_addr,
+						usb_dev_desc[device].blksz);
+		if (blks > max_xfer_blk)
+			smallblks = (unsigned short) max_xfer_blk;
 		else
 			smallblks = (unsigned short) blks;
 retry_it:
-		if (smallblks == ss->max_xfer_blk)
+		if (smallblks == max_xfer_blk)
 			usb_show_progress();
 		srb->datalen = usb_dev_desc[device].blksz * smallblks;
 		srb->pdata = (unsigned char *)buf_addr;
@@ -1188,7 +1197,7 @@ retry_it:
 			start, smallblks, buf_addr);
 
 	usb_disable_asynch(0); /* asynch transfer allowed */
-	if (blkcnt >= ss->max_xfer_blk)
+	if (blkcnt >= max_xfer_blk)
 		debug("\n");
 	return blkcnt;
 
@@ -1415,12 +1424,6 @@ int usb_stor_get_info(struct usb_device *dev, struct us_data *ss,
 	USB_STOR_PRINTF(" address %d\n", dev_desc->target);
 	USB_STOR_PRINTF("partype: %d\n", dev_desc->part_type);
 
-	/*
-	 * The U-Boot EHCI driver cannot handle more than 4096 * 5 bytes in a
-	 * transfer without running itself out of qt_buffers.
-	 */
-	ss->max_xfer_blk = (4096 * 5) / dev_desc->blksz;
-
 	init_part(dev_desc);
 
 	USB_STOR_PRINTF("partype: %d\n", dev_desc->part_type);
Signature · 1 line
1.7.9.5
#10 lore raw

PATCH v2 1/1 usb_storage: fix ehci driver max transfer size

Dear Stefan Herbrechtsmeier,

Quoted 7 lines

The commit 5dd95cf93dfffa1d19a1928990852aac9f55b9d9 'usb_storage:
Fix EHCI "out of buffer pointers" with CD-ROM' introduce a bug in usb_storage as it wrongly assumes that every transfer can use 4096 bytes per qt_buffer. This is wrong if the start address of the data is not page aligned to 4096 bytes and leads to 'EHCI timed out on TD' messages because of 'out of buffer pointers' in ehci_td_buffer function.

Yes, this can be simply confirmed even with USB stick by loading to unaligned address. It'll make the buffers overflow too.

Quoted 33 lines

The bug appears during load of a fragmented file and read from or write to an unaligned memory address.

---
Changes for v2:
- Replace fixed worst case calculation with dynamic computation based on start address of transfer

 common/usb_storage.c |   37 ++++++++++++++++++++-----------------
 1 file changed, 20 insertions(+), 17 deletions(-)
common/usb_storage.c +5 -1
index faad237..bdc306f 100644
@@ -150,12 +150,17 @@ struct us_data {
 	unsigned int	irqpipe;	 	/* pipe for release_irq */
 	unsigned char	irqmaxp;		/* max packed for irq Pipe */
 	unsigned char	irqinterval;		/* Intervall for IRQ Pipe */
-	unsigned long	max_xfer_blk;		/* Max blocks per xfer */
 	ccb		*srb;			/* current srb */
 	trans_reset	transport_reset;	/* reset routine */
 	trans_cmnd	transport;		/* transport routine */
 };
 
+/*
+ * The U-Boot EHCI driver cannot handle more than 5 page aligned buffers
+ * of 4096 bytes in a transfer without running itself out of qt_buffers
+ */
+#define USB_MAX_XFER_BLK(start, blksz)	(((4096 * 5) - (start % 4096)) /
Quoted 1 line

blksz) +

Can't something in include/common.h around line 900 can't be used?

btw put braces around (start) in the macro and around (blksz) .

[...]

The rest is good, thanks! :-)

Best regards,
Marek Vasut

#11 lore raw

PATCH v2 1/1 usb_storage: fix ehci driver max transfer size

Am 10.07.2012 04:12, schrieb Marek Vasut:

Quoted 38 lines
Quoted 7 lines

The commit 5dd95cf93dfffa1d19a1928990852aac9f55b9d9 'usb_storage:
Fix EHCI "out of buffer pointers" with CD-ROM' introduce a bug in usb_storage as it wrongly assumes that every transfer can use 4096 bytes per qt_buffer. This is wrong if the start address of the data is not page aligned to 4096 bytes and leads to 'EHCI timed out on TD' messages because of 'out of buffer pointers' in ehci_td_buffer function.

Yes, this can be simply confirmed even with USB stick by loading to unaligned address. It'll make the buffers overflow too.

Quoted 28 lines

The bug appears during load of a fragmented file and read from or write to an unaligned memory address.

---
Changes for v2:
- Replace fixed worst case calculation with dynamic computation based on start address of transfer

  common/usb_storage.c |   37 ++++++++++++++++++++-----------------
  1 file changed, 20 insertions(+), 17 deletions(-)
common/usb_storage.c +0 -1
index faad237..bdc306f 100644
@@ -150,12 +150,17 @@ struct us_data {
  	unsigned int	irqpipe;	 	/* pipe for release_irq */
  	unsigned char	irqmaxp;		/* max packed for irq Pipe */
  	unsigned char	irqinterval;		/* Intervall for IRQ Pipe */
-	unsigned long	max_xfer_blk;		/* Max blocks per xfer */
  	ccb		*srb;			/* current srb */
  	trans_reset	transport_reset;	/* reset routine */
  	trans_cmnd	transport;		/* transport routine */
  };
 
Quoted 7 lines
Quoted 6 lines
common/usb_storage.c +5 -0
+/*
+ * The U-Boot EHCI driver cannot handle more than 5 page aligned buffers
+ * of 4096 bytes in a transfer without running itself out of qt_buffers
+ */
+#define USB_MAX_XFER_BLK(start, blksz)	(((4096 * 5) - (start % 4096)) /

blksz) +

Can't something in include/common.h around line 900 can't be used?

If you mean the round functions I don't need them, as I need the leftover of 4096 and I need to divide round down the count.

Quoted 1 line

btw put braces around (start) in the macro and around (blksz) .

I will send a v3 tonight.

Regards,
Stefan

#12 lore raw

PATCH v2 1/1 usb_storage: fix ehci driver max transfer size

Dear Stefan Herbrechtsmeier,

Quoted 55 lines

Am 10.07.2012 04:12, schrieb Marek Vasut:

Quoted 45 lines
Quoted 7 lines

The commit 5dd95cf93dfffa1d19a1928990852aac9f55b9d9 'usb_storage:
Fix EHCI "out of buffer pointers" with CD-ROM' introduce a bug in usb_storage as it wrongly assumes that every transfer can use 4096 bytes per qt_buffer. This is wrong if the start address of the data is not page aligned to 4096 bytes and leads to 'EHCI timed out on TD' messages because of 'out of buffer pointers' in ehci_td_buffer function.

Yes, this can be simply confirmed even with USB stick by loading to unaligned address. It'll make the buffers overflow too.

Quoted 34 lines

The bug appears during load of a fragmented file and read from or write to an unaligned memory address.

---

Changes for v2:
- Replace fixed worst case calculation with dynamic

computation based on start address of transfer

  common/usb_storage.c |   37 ++++++++++++++++++++-----------------
  1 file changed, 20 insertions(+), 17 deletions(-)
common/usb_storage.c +0 -1
index faad237..bdc306f 100644
@@ -150,12 +150,17 @@ struct us_data {
 
  	unsigned int	irqpipe;	 	/* pipe for release_irq */
  	unsigned char	irqmaxp;		/* max packed for irq Pipe */
  	unsigned char	irqinterval;		/* Intervall for IRQ Pipe */
 
-	unsigned long	max_xfer_blk;		/* Max blocks per xfer */
 
  	ccb		*srb;			/* current srb */
  	trans_reset	transport_reset;	/* reset routine */
  	trans_cmnd	transport;		/* transport routine */
 
  };
Quoted 8 lines
Quoted 6 lines
common/usb_storage.c +2 -0
+/*
+ * The U-Boot EHCI driver cannot handle more than 5 page aligned

buffers + * of 4096 bytes in a transfer without running itself out of qt_buffers + */
+#define USB_MAX_XFER_BLK(start, blksz) (((4096 * 5) - (start % 4096)) /
blksz) +

Can't something in include/common.h around line 900 can't be used?

Quoted 6 lines

If you mean the round functions I don't need them, as I need the leftover of 4096 and I need to divide round down the count.

Quoted 1 line

btw put braces around (start) in the macro and around (blksz) .

I will send a v3 tonight.

Ok then, I think this is just perfect than and it should definitelly hit this release :-)

Thank you very much, sorry for pestering you too much and adding delays. Shame on my maintaining skills.

Quoted 2 lines

Regards,
Stefan

Best regards,
Marek Vasut

#13 lore raw

PATCH v2 1/1 usb_storage: fix ehci driver max transfer size

In reply to Stefan Herbrechtsmeier

The commit 5dd95cf93dfffa1d19a1928990852aac9f55b9d9 'usb_storage:
Fix EHCI "out of buffer pointers" with CD-ROM' introduce a bug in usb_storage as it wrongly assumes that every transfer can use 4096 bytes per qt_buffer. This is wrong if the start address of the data is not page aligned to 4096 bytes and leads to 'EHCI timed out on TD' messages because of 'out of buffer pointers' in ehci_td_buffer function.

The bug appears during load of a fragmented file and read from or write to an unaligned memory address.

---
Changes for v2:
- Replace fixed worst case calculation with dynamic computation based on start address of transfer
Changes for v3:
- Add parentheses within macro around parameters

 common/usb_storage.c |   38 +++++++++++++++++++++-----------------
 1 file changed, 21 insertions(+), 17 deletions(-)
common/usb_storage.c +21 -17
index faad237..c528979 100644
@@ -150,12 +150,18 @@ struct us_data {
 	unsigned int	irqpipe;	 	/* pipe for release_irq */
 	unsigned char	irqmaxp;		/* max packed for irq Pipe */
 	unsigned char	irqinterval;		/* Intervall for IRQ Pipe */
-	unsigned long	max_xfer_blk;		/* Max blocks per xfer */
 	ccb		*srb;			/* current srb */
 	trans_reset	transport_reset;	/* reset routine */
 	trans_cmnd	transport;		/* transport routine */
 };
 
+/*
+ * The U-Boot EHCI driver cannot handle more than 5 page aligned buffers
+ * of 4096 bytes in a transfer without running itself out of qt_buffers
+ */
+#define USB_MAX_XFER_BLK(start, blksz) \
+	(((4096 * 5) - ((start) % 4096)) / (blksz))
+
 static struct us_data usb_stor[USB_MAX_STOR_DEV];
 
 
@@ -1041,7 +1047,7 @@ static void usb_bin_fixup(struct usb_device_descriptor descriptor,
 unsigned long usb_stor_read(int device, unsigned long blknr,
 			    unsigned long blkcnt, void *buffer)
 {
-	unsigned long start, blks, buf_addr;
+	unsigned long start, blks, buf_addr, max_xfer_blk;
 	unsigned short smallblks;
 	struct usb_device *dev;
 	struct us_data *ss;
@@ -1083,12 +1089,14 @@ unsigned long usb_stor_read(int device, unsigned long blknr,
 		/* XXX need some comment here */
 		retry = 2;
 		srb->pdata = (unsigned char *)buf_addr;
-		if (blks > ss->max_xfer_blk)
-			smallblks = ss->max_xfer_blk;
+		max_xfer_blk = USB_MAX_XFER_BLK(buf_addr,
+						usb_dev_desc[device].blksz);
+		if (blks > max_xfer_blk)
+			smallblks = (unsigned short) max_xfer_blk;
 		else
 			smallblks = (unsigned short) blks;
 retry_it:
-		if (smallblks == ss->max_xfer_blk)
+		if (smallblks == max_xfer_blk)
 			usb_show_progress();
 		srb->datalen = usb_dev_desc[device].blksz * smallblks;
 		srb->pdata = (unsigned char *)buf_addr;
@@ -1109,7 +1117,7 @@ retry_it:
 			start, smallblks, buf_addr);
 
 	usb_disable_asynch(0); /* asynch transfer allowed */
-	if (blkcnt >= ss->max_xfer_blk)
+	if (blkcnt >= max_xfer_blk)
 		debug("\n");
 	return blkcnt;
 }
@@ -1117,7 +1125,7 @@ retry_it:
 unsigned long usb_stor_write(int device, unsigned long blknr,
 				unsigned long blkcnt, const void *buffer)
 {
-	unsigned long start, blks, buf_addr;
+	unsigned long start, blks, buf_addr, max_xfer_blk;
 	unsigned short smallblks;
 	struct usb_device *dev;
 	struct us_data *ss;
@@ -1162,12 +1170,14 @@ unsigned long usb_stor_write(int device, unsigned long blknr,
 		 */
 		retry = 2;
 		srb->pdata = (unsigned char *)buf_addr;
-		if (blks > ss->max_xfer_blk)
-			smallblks = ss->max_xfer_blk;
+		max_xfer_blk = USB_MAX_XFER_BLK(buf_addr,
+						usb_dev_desc[device].blksz);
+		if (blks > max_xfer_blk)
+			smallblks = (unsigned short) max_xfer_blk;
 		else
 			smallblks = (unsigned short) blks;
 retry_it:
-		if (smallblks == ss->max_xfer_blk)
+		if (smallblks == max_xfer_blk)
 			usb_show_progress();
 		srb->datalen = usb_dev_desc[device].blksz * smallblks;
 		srb->pdata = (unsigned char *)buf_addr;
@@ -1188,7 +1198,7 @@ retry_it:
 			start, smallblks, buf_addr);
 
 	usb_disable_asynch(0); /* asynch transfer allowed */
-	if (blkcnt >= ss->max_xfer_blk)
+	if (blkcnt >= max_xfer_blk)
 		debug("\n");
 	return blkcnt;
 
@@ -1415,12 +1425,6 @@ int usb_stor_get_info(struct usb_device *dev, struct us_data *ss,
 	USB_STOR_PRINTF(" address %d\n", dev_desc->target);
 	USB_STOR_PRINTF("partype: %d\n", dev_desc->part_type);
 
-	/*
-	 * The U-Boot EHCI driver cannot handle more than 4096 * 5 bytes in a
-	 * transfer without running itself out of qt_buffers.
-	 */
-	ss->max_xfer_blk = (4096 * 5) / dev_desc->blksz;
-
 	init_part(dev_desc);
 
 	USB_STOR_PRINTF("partype: %d\n", dev_desc->part_type);
Signature · 1 line
1.7.9.5
#14 lore raw

PATCH v2 1/1 usb_storage: fix ehci driver max transfer size

Dear Stefan Herbrechtsmeier,

Quoted 8 lines

The commit 5dd95cf93dfffa1d19a1928990852aac9f55b9d9 'usb_storage:
Fix EHCI "out of buffer pointers" with CD-ROM' introduce a bug in usb_storage as it wrongly assumes that every transfer can use 4096 bytes per qt_buffer. This is wrong if the start address of the data is not page aligned to 4096 bytes and leads to 'EHCI timed out on TD' messages because of 'out of buffer pointers' in ehci_td_buffer function.

Quoted 5 lines

The bug appears during load of a fragmented file and read from or write to an unaligned memory address.

This one is good :-)

Thank you, Stefan! For your contribution and your patience.

I'll test it on friday and I'll talk to WD to include it in current release. The fix looks very reasonable. Though I'd like to get some tests done. Tom, Ilya, can you possibly try this on your toys please?
[...]

Best regards,
Marek Vasut

#15 lore raw

PATCH v2 1/1 usb_storage: fix ehci driver max transfer size

Hi,

The patch is good in the sense it does fix the real problem. But I wonder if it's a good idea to expose lower layer details (like size/number of buffers per EHCI TD) to upper layer driver? I know EHCI is most common USB HCD but we have drivers for a bunch of others... How about them?

Regards, Ilya.

#16 lore raw

PATCH v2 1/1 usb_storage: fix ehci driver max transfer size

Dear Ilya Yanok,

Quoted 6 lines

Hi,

The patch is good in the sense it does fix the real problem. But I wonder if it's a good idea to expose lower layer details (like size/number of buffers per EHCI TD) to upper layer driver? I know EHCI is most common USB HCD but we have drivers for a bunch of others... How about them?

No, it's not ... it's yet another usb-is-full-of-crap-in-uboot kind of bugs :-(

I'd like to queue this for the current release, we can work on proper rework for -next. Agreed?

Quoted 1 line

Regards, Ilya.

Best regards,
Marek Vasut

#17 lore raw

PATCH v2 1/1 usb_storage: fix ehci driver max transfer size

Dear Marek,

Quoted 7 lines · Marek Vasut
Quoted 3 lines

The patch is good in the sense it does fix the real problem. But I wonder if it's a good idea to expose lower layer details (like size/number of buffers per EHCI TD) to upper layer driver? I know EHCI is most common

USB

Quoted 1 line

HCD but we have drivers for a bunch of others... How about them?

Quoted 7 lines

No, it's not ... it's yet another usb-is-full-of-crap-in-uboot kind of bugs :-(

I'd like to queue this for the current release, we can work on proper rework for
-next. Agreed?

Agreed,

Regards, Ilya.

#18 lore raw

PATCH v2 1/1 usb_storage: fix ehci driver max transfer size

Dear Ilya Yanok,

Quoted 12 lines

Dear Marek,

Quoted 9 lines · Marek Vasut
Quoted 4 lines

The patch is good in the sense it does fix the real problem. But I wonder if it's a good idea to expose lower layer details (like size/number of buffers per EHCI TD) to upper layer driver? I know EHCI is most common

USB

Quoted 1 line

HCD but we have drivers for a bunch of others... How about them?

Quoted 8 lines
Quoted 6 lines

No, it's not ... it's yet another usb-is-full-of-crap-in-uboot kind of bugs :-(

I'd like to queue this for the current release, we can work on proper rework for
-next. Agreed?

Agreed,

Thanks! I'm marking this important in my mailbox to avoid missing that we need to fix this. Ilya, can you check the driver model papers and see if we can somehow integrate this into that?

Quoted 1 line

Regards, Ilya.

Best regards,
Marek Vasut

#19 lore raw

PATCH v2 1/1 usb_storage: fix ehci driver max transfer size

Dear Marek,

Quoted 7 lines · Marek Vasut

Thanks! I'm marking this important in my mailbox to avoid missing that we need
to fix this. Ilya, can you check the driver model papers and see if we can somehow integrate this into that?

I will try to.

Regards, Ilya.

Applied
#20 lore raw

PATCH v2 1/1 usb_storage: fix ehci driver max transfer size

In reply to Stefan Herbrechtsmeier

Dear Wolfgang Denk,

Quoted 8 lines

The commit 5dd95cf93dfffa1d19a1928990852aac9f55b9d9 'usb_storage:
Fix EHCI "out of buffer pointers" with CD-ROM' introduce a bug in usb_storage as it wrongly assumes that every transfer can use 4096 bytes per qt_buffer. This is wrong if the start address of the data is not page aligned to 4096 bytes and leads to 'EHCI timed out on TD' messages because of 'out of buffer pointers' in ehci_td_buffer function.

Quoted 5 lines

The bug appears during load of a fragmented file and read from or write to an unaligned memory address.

I'd like to get this patch:

http://patchwork.ozlabs.org/patch/170256/

applied into current release. If you consider a pullRQ is better, I'll prepare one.

Best regards,
Marek Vasut

#21 lore raw

PATCH v2 1/1 usb_storage: fix ehci driver max transfer size

In reply to Stefan Herbrechtsmeier

Dear Stefan Herbrechtsmeier,

Quoted 8 lines

The commit 5dd95cf93dfffa1d19a1928990852aac9f55b9d9 'usb_storage:
Fix EHCI "out of buffer pointers" with CD-ROM' introduce a bug in usb_storage as it wrongly assumes that every transfer can use 4096 bytes per qt_buffer. This is wrong if the start address of the data is not page aligned to 4096 bytes and leads to 'EHCI timed out on TD' messages because of 'out of buffer pointers' in ehci_td_buffer function.

Quoted 5 lines

The bug appears during load of a fragmented file and read from or write to an unaligned memory address.

[...]

I applied this and pushed into u-boot-usb. Thanks again for finding and fixing this.

I'm still uncertain if we should add it into current release so late, probably not though. Therefore I'll queue it for next, ok?

Best regards,
Marek Vasut

#22 lore raw

PATCH v2 1/1 usb_storage: fix ehci driver max transfer size

Am 18.07.2012 14:50, schrieb Marek Vasut:

Quoted 13 lines
Quoted 8 lines

The commit 5dd95cf93dfffa1d19a1928990852aac9f55b9d9 'usb_storage:
Fix EHCI "out of buffer pointers" with CD-ROM' introduce a bug in usb_storage as it wrongly assumes that every transfer can use 4096 bytes per qt_buffer. This is wrong if the start address of the data is not page aligned to 4096 bytes and leads to 'EHCI timed out on TD' messages because of 'out of buffer pointers' in ehci_td_buffer function.

Quoted 5 lines

The bug appears during load of a fragmented file and read from or write to an unaligned memory address.

Quoted 7 lines

[...]

I applied this and pushed into u-boot-usb. Thanks again for finding and fixing this.

I'm still uncertain if we should add it into current release so late, probably not though. Therefore I'll queue it for next, ok?

Given that there was nobody other than me with the problem until now, it should be okay.

Regards,
Stefan