Re: [PATCH v5 16/16] usb: gadget: UMS: fix 64-bit division on ARM32

[Caleb Connolly]

Hi Mattijs,

On 02/04/2024 09:24, Mattijs Korpershoek wrote:
Hi Caleb,
Thank you for the patch.

On jeu., mars 28, 2024 at 17:59, Caleb Connolly <caleb.conno...@linaro.org> 
wrote:

The patch introducing support for dynamic sector sizes changed the types
used in some divisions, resulting in the compiler attempting to use
libgcc helpers (__aeabi_ldivmod). Replace these divisions with calls to
lldiv() to handle this correctly.

Fixes: 74e56e0c5065 ("usb: gadget: UMS: support multiple sector sizes")
Signed-off-by: Caleb Connolly <caleb.conno...@linaro.org>

I believe I applied this already via [1]

Oh yes of course, I'm not sure quite how this patch ended up in my 
outbox, apologies for any confusion.

I plan to send your work to Tom this week.

Sorry for the delay!

No problem at all.

Thanks,

[1] https://lore.kernel.org/r/87a5mqei67....@baylibre.com

---
Cc: Mattijs Korpershoek <mkorpersh...@baylibre.com>
---
  drivers/usb/gadget/f_mass_storage.c | 13 +++++++------
  1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/drivers/usb/gadget/f_mass_storage.c 
b/drivers/usb/gadget/f_mass_storage.c
index d880928044f4..ef90c7ec7fb5 100644
--- a/drivers/usb/gadget/f_mass_storage.c
+++ b/drivers/usb/gadget/f_mass_storage.c
@@ -239,8 +239,9 @@
  /* #define VERBOSE_DEBUG */
  /* #define DUMP_MSGS */
  
  #include <config.h>
+#include <div64.h>
  #include <hexdump.h>
  #include <log.h>
  #include <malloc.h>
  #include <common.h>
@@ -768,10 +769,10 @@ static int do_read(struct fsg_common *common)
                }
  
  		/* Perform the read */
                rc = ums[common->lun].read_sector(&ums[common->lun],
-                                     file_offset / curlun->blksize,
-                                     amount / curlun->blksize,
+                                     lldiv(file_offset, curlun->blksize),
+                                     lldiv(amount, curlun->blksize),
                                      (char __user *)bh->buf);
                if (!rc)
                        return -EIO;
  
@@ -942,10 +943,10 @@ static int do_write(struct fsg_common *common)
                        amount = bh->outreq->actual;
  
  			/* Perform the write */
                        rc = ums[common->lun].write_sector(&ums[common->lun],
-                                              file_offset / curlun->blksize,
-                                              amount / curlun->blksize,
+                                              lldiv(file_offset, 
curlun->blksize),
+                                              lldiv(amount, curlun->blksize),
                                               (char __user *)bh->buf);
                        if (!rc)
                                return -EIO;
                        nwritten = rc * curlun->blksize;
@@ -1058,10 +1059,10 @@ static int do_verify(struct fsg_common *common)
                }
  
  		/* Perform the read */
                rc = ums[common->lun].read_sector(&ums[common->lun],
-                                     file_offset / curlun->blksize,
-                                     amount / curlun->blksize,
+                                     lldiv(file_offset, curlun->blksize),
+                                     lldiv(amount, curlun->blksize),
                                      (char __user *)bh->buf);
                if (!rc)
                        return -EIO;
                nread = rc * curlun->blksize;

--
2.44.0

--
// Caleb (they/them)