linux-sg2042/drivers/scsi/mpt3sas
Arnd Bergmann 6f9e09fd64 scsi: mpt3sas: clarify mmio pointer types
The newly added code mixes up phys_addr_t/resource_size_t with dma_addr_t
and void pointers, as seen from these compiler warning:

drivers/scsi/mpt3sas/mpt3sas_base.c: In function '_base_get_chain_phys':
drivers/scsi/mpt3sas/mpt3sas_base.c:235:21: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
  base_chain_phys  = (void *)ioc->chip_phys + MPI_FRAME_START_OFFSET +
                     ^
drivers/scsi/mpt3sas/mpt3sas_base.c: In function '_clone_sg_entries':
drivers/scsi/mpt3sas/mpt3sas_base.c:427:20: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
    sgel->Address = (dma_addr_t)dst_addr_phys;
                    ^
drivers/scsi/mpt3sas/mpt3sas_base.c:438:7: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
       (dma_addr_t)buff_ptr_phys;
       ^
drivers/scsi/mpt3sas/mpt3sas_base.c:444:10: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
          (dma_addr_t)buff_ptr_phys;

Both dma_addr_t and phys_addr_t may be wider than a pointer, so we must
avoid the conversion to pointer types. This also helps readability.

A second problem is treating MMIO addresses from a 'struct resource'
as addresses that can be used for DMA on that device. In almost all
cases, those are the same, but on some of the more obscure architectures,
PCI memory address 0 is mapped into the CPU address space at a nonzero
offset. I don't have a good fix for that, so I'm adding a comment here,
plus a WARN_ON() that triggers whenever the phys_addr_t number is
outside of the low 32-bit address space and causes a straight overflow
when assigned to the 32-bit sgel->Address.

Fixes: 182ac784b4 ("scsi: mpt3sas: Introduce Base function for cloning.")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Sreekanth Reddy <Sreekanth.Reddy@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-03-06 13:06:10 -05:00
..
mpi scsi: mpt3sas: Add PCI device ID for Andromeda. 2018-02-27 22:26:12 -05:00
Kconfig mpt3sas: fix Kconfig dependency problem for mpt2sas back compatibility 2015-12-03 09:31:23 -08:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
mpt3sas_base.c scsi: mpt3sas: clarify mmio pointer types 2018-03-06 13:06:10 -05:00
mpt3sas_base.h scsi: mpt3sas: clarify mmio pointer types 2018-03-06 13:06:10 -05:00
mpt3sas_config.c scsi: mpt3sas: Do not use 32-bit atomic request descriptor for Ventura controllers. 2018-02-27 22:26:16 -05:00
mpt3sas_ctl.c scsi: mpt3sas: Do not use 32-bit atomic request descriptor for Ventura controllers. 2018-02-27 22:26:16 -05:00
mpt3sas_ctl.h scripts/spelling.txt: add "overwritting" pattern and fix typo instances 2017-02-27 18:43:47 -08:00
mpt3sas_debug.h mpt2sas, mpt3sas: Remove SCSI_MPTXSAS_LOGGING entry from Kconfig 2015-11-11 18:31:14 -05:00
mpt3sas_scsih.c scsi: mpt3sas: Do not use 32-bit atomic request descriptor for Ventura controllers. 2018-02-27 22:26:16 -05:00
mpt3sas_transport.c scsi: mpt3sas: Do not use 32-bit atomic request descriptor for Ventura controllers. 2018-02-27 22:26:16 -05:00
mpt3sas_trigger_diag.c mpt2sas, mpt3sas: Update attribution language to Avago 2015-01-13 16:27:27 +01:00
mpt3sas_trigger_diag.h mpt2sas, mpt3sas: Update attribution language to Avago 2015-01-13 16:27:27 +01:00
mpt3sas_warpdrive.c scsi: mpt3sas: lockless command submission 2018-01-10 23:25:04 -05:00