Subject: [merged] scsi_debug-fix-do_device_access-with-wrap-around-range.patch removed from -mm tree To: akinobu.mita@xxxxxxxxx,JBottomley@xxxxxxxxxxxxx,davem@xxxxxxxxxxxxx,dgilbert@xxxxxxxxxxxx,herbert@xxxxxxxxxxxxxxxxxxx,horia.geanta@xxxxxxxxxxxxx,imre.deak@xxxxxxxxx,tj@xxxxxxxxxx,mm-commits@xxxxxxxxxxxxxxx From: akpm@xxxxxxxxxxxxxxxxxxxx Date: Tue, 09 Jul 2013 16:22:37 -0700 The patch titled Subject: scsi_debug: fix do_device_access() with wrap around range has been removed from the -mm tree. Its filename was scsi_debug-fix-do_device_access-with-wrap-around-range.patch This patch was dropped because it was merged into mainline or a subsystem tree ------------------------------------------------------ From: Akinobu Mita <akinobu.mita@xxxxxxxxx> Subject: scsi_debug: fix do_device_access() with wrap around range do_device_access() is a function that abstracts copying SG list from/to ramdisk storage (fake_storep). It must deal with the ranges exceeding actual fake_storep size, because such ranges are valid if virtual_gb is set greater than zero, and they should be treated as fake_storep is repeatedly mirrored up to virtual size. Unfortunately, it can't deal with the range which wraps around the end of fake_storep. A wrap around range is copied by two sg_copy_{from,to}_buffer() calls, but sg_copy_{from,to}_buffer() can't copy from/to in the middle of SG list, therefore the second call can't copy correctly. This fixes it by using sg_pcopy_{from,to}_buffer() that can copy from/to the middle of SG list. This also simplifies the assignment of sdb->resid in fill_from_dev_buffer(). Because fill_from_dev_buffer() is now only called once per command execution cycle. So it is not necessary to take care to decrease sdb->resid if fill_from_dev_buffer() is called more than once. Signed-off-by: Akinobu Mita <akinobu.mita@xxxxxxxxx> Cc: "David S. Miller" <davem@xxxxxxxxxxxxx> Cc: "James E.J. Bottomley" <JBottomley@xxxxxxxxxxxxx> Cc: Douglas Gilbert <dgilbert@xxxxxxxxxxxx> Cc: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> Cc: Horia Geanta <horia.geanta@xxxxxxxxxxxxx> Cc: Imre Deak <imre.deak@xxxxxxxxx> Cc: Tejun Heo <tj@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- drivers/scsi/scsi_debug.c | 48 +++++++++++++++++++++++++++--------- 1 file changed, 37 insertions(+), 11 deletions(-) diff -puN drivers/scsi/scsi_debug.c~scsi_debug-fix-do_device_access-with-wrap-around-range drivers/scsi/scsi_debug.c --- a/drivers/scsi/scsi_debug.c~scsi_debug-fix-do_device_access-with-wrap-around-range +++ a/drivers/scsi/scsi_debug.c @@ -439,10 +439,7 @@ static int fill_from_dev_buffer(struct s act_len = sg_copy_from_buffer(sdb->table.sgl, sdb->table.nents, arr, arr_len); - if (sdb->resid) - sdb->resid -= act_len; - else - sdb->resid = scsi_bufflen(scp) - act_len; + sdb->resid = scsi_bufflen(scp) - act_len; return 0; } @@ -1693,24 +1690,48 @@ static int check_device_access_params(st return 0; } +/* Returns number of bytes copied or -1 if error. */ static int do_device_access(struct scsi_cmnd *scmd, struct sdebug_dev_info *devi, unsigned long long lba, unsigned int num, int write) { int ret; unsigned long long block, rest = 0; - int (*func)(struct scsi_cmnd *, unsigned char *, int); + struct scsi_data_buffer *sdb; + enum dma_data_direction dir; + size_t (*func)(struct scatterlist *, unsigned int, void *, size_t, + off_t); + + if (write) { + sdb = scsi_out(scmd); + dir = DMA_TO_DEVICE; + func = sg_pcopy_to_buffer; + } else { + sdb = scsi_in(scmd); + dir = DMA_FROM_DEVICE; + func = sg_pcopy_from_buffer; + } - func = write ? fetch_to_dev_buffer : fill_from_dev_buffer; + if (!sdb->length) + return 0; + if (!(scsi_bidi_cmnd(scmd) || scmd->sc_data_direction == dir)) + return -1; block = do_div(lba, sdebug_store_sectors); if (block + num > sdebug_store_sectors) rest = block + num - sdebug_store_sectors; - ret = func(scmd, fake_storep + (block * scsi_debug_sector_size), - (num - rest) * scsi_debug_sector_size); - if (!ret && rest) - ret = func(scmd, fake_storep, rest * scsi_debug_sector_size); + ret = func(sdb->table.sgl, sdb->table.nents, + fake_storep + (block * scsi_debug_sector_size), + (num - rest) * scsi_debug_sector_size, 0); + if (ret != (num - rest) * scsi_debug_sector_size) + return ret; + + if (rest) { + ret += func(sdb->table.sgl, sdb->table.nents, + fake_storep, rest * scsi_debug_sector_size, + (num - rest) * scsi_debug_sector_size); + } return ret; } @@ -1849,7 +1870,12 @@ static int resp_read(struct scsi_cmnd *S read_lock_irqsave(&atomic_rw, iflags); ret = do_device_access(SCpnt, devip, lba, num, 0); read_unlock_irqrestore(&atomic_rw, iflags); - return ret; + if (ret == -1) + return DID_ERROR << 16; + + scsi_in(SCpnt)->resid = scsi_bufflen(SCpnt) - ret; + + return 0; } void dump_sector(unsigned char *buf, int len) _ Patches currently in -mm which might be from akinobu.mita@xxxxxxxxx are origin.patch linux-next.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html