[PATCH] USB Storage: more sddr09 cleanups

This is the third of three patches to prepare the sddr09 subdriver for
conversion to the Sim-SCSI framework.  This patch (as596) moves the
computation of the LBA to the start of the read/write routines, so that
addresses completely beyond the end of the device can be detected and
reported differently from transfers that are partially within the
device's capacity.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Andries Brouwer <Andries.Brouwer@cwi.nl>
Signed-off-by: Matthew Dharm <mdharm-usb@one-eyed-alien.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/storage/sddr09.c b/drivers/usb/storage/sddr09.c
index 760fe9362b6d96f4ca1bb43e3cf25ac1e262a00c..b8e7802c871d91237908d5afd7f403448c849932 100644 (file)
--- a/drivers/usb/storage/sddr09.c
+++ b/drivers/usb/storage/sddr09.c
@@ -711,6 +711,13 @@ sddr09_read_data(struct us_data *us,
        unsigned int len, index, offset;
        int result;
 
+       // Figure out the initial LBA and page
+       lba = address >> info->blockshift;
+       page = (address & info->blockmask);
+       maxlba = info->capacity >> (info->pageshift + info->blockshift);
+       if (lba >= maxlba)
+               return -EIO;
+
        // Since we only read in one block at a time, we have to create
        // a bounce buffer and move the data a piece at a time between the
        // bounce buffer and the actual transfer buffer.
@@ -722,11 +729,6 @@ sddr09_read_data(struct us_data *us,
                return -ENOMEM;
        }
 
-       // Figure out the initial LBA and page
-       lba = address >> info->blockshift;
-       page = (address & info->blockmask);
-       maxlba = info->capacity >> (info->pageshift + info->blockshift);
-
        // This could be made much more efficient by checking for
        // contiguous LBA's. Another exercise left to the student.
 
@@ -928,13 +930,20 @@ sddr09_write_data(struct us_data *us,
                  unsigned int sectors) {
 
        struct sddr09_card_info *info = (struct sddr09_card_info *) us->extra;
-       unsigned int lba, page, pages;
+       unsigned int lba, maxlba, page, pages;
        unsigned int pagelen, blocklen;
        unsigned char *blockbuffer;
        unsigned char *buffer;
        unsigned int len, index, offset;
        int result;
 
+       // Figure out the initial LBA and page
+       lba = address >> info->blockshift;
+       page = (address & info->blockmask);
+       maxlba = info->capacity >> (info->pageshift + info->blockshift);
+       if (lba >= maxlba)
+               return -EIO;
+
        // blockbuffer is used for reading in the old data, overwriting
        // with the new data, and performing ECC calculations
 
@@ -961,10 +970,6 @@ sddr09_write_data(struct us_data *us,
                return -ENOMEM;
        }
 
-       // Figure out the initial LBA and page
-       lba = address >> info->blockshift;
-       page = (address & info->blockmask);
-
        result = 0;
        index = offset = 0;
 
@@ -975,6 +980,14 @@ sddr09_write_data(struct us_data *us,
                pages = min(sectors, info->blocksize - page);
                len = (pages << info->pageshift);
 
+               /* Not overflowing capacity? */
+               if (lba >= maxlba) {
+                       US_DEBUGP("Error: Requested lba %u exceeds "
+                                 "maximum %u\n", lba, maxlba);
+                       result = -EIO;
+                       break;
+               }
+
                // Get the data from the transfer buffer
                usb_stor_access_xfer_buf(buffer, len, us->srb,
                                &index, &offset, FROM_XFER_BUF);