qla1280: user pci_map_single
Subsystems (2)
PATCH 2/3 qla1280: user pci_map_single
drivers/scsi/qla1280.c +12 -20
@@ -1571,16 +1465,12 @@ qla1280_done(struct scsi_qla_host *ha)/* Release memory used for this I/O */ if (cmd->use_sg) { -dprintk (3 ,"S/G unmap_sg cmd=%p\n" , cmd); -pci_unmap_sg (ha->pdev, cmd->request_buffer, - cmd->use_sg, cmd->sc_data_direction); + cmd->use_sg, cmd->sc_data_direction); }else if (cmd->request_bufflen) { -/*dprintk(1, "No S/G unmap_single cmd=%x saved_dma_handle=%lx\n", -cmd, sp->saved_dma_handle); */ - -pci_unmap_page (ha->pdev, sp->saved_dma_handle, - cmd->request_bufflen, cmd->sc_data_direction); +pci_unmap_single (ha->pdev, sp->saved_dma_handle, + cmd->request_bufflen, + cmd->sc_data_direction); }/* Call the mid-level driver interrupt handler */
@@ -3354,14 +3244,11 @@ qla1280_64bit_start_scsi(struct scsi_qla REQUEST_ENTRY_SIZE); } }else {/* No scatter gather data transfer */ -struct page *page =virt_to_page (cmd->request_buffer); -unsigned long off = (unsigned long )cmd->request_buffer & ~PAGE_MASK ; - - dma_handle =pci_map_page (ha->pdev, page, off, - cmd->request_bufflen, - cmd->sc_data_direction); + dma_handle =pci_map_single (ha->pdev, + cmd->request_buffer, + cmd->request_bufflen, + cmd->sc_data_direction); -/* save dma_handle for pci_unmap_page */ sp->saved_dma_handle = dma_handle;#if defined(CONFIG_IA64_GENERIC ) || defined(CONFIG_IA64_SGI_SN2 )if (ha->flags.use_pci_vchannel)
@@ -3636,11 +3523,10 @@ qla1280_32bit_start_scsi(struct scsi_qla REQUEST_ENTRY_SIZE); } }else {/* No S/G data transfer */ -struct page *page =virt_to_page (cmd->request_buffer); -unsigned long off = (unsigned long )cmd->request_buffer & ~PAGE_MASK ; - dma_handle =pci_map_page (ha->pdev, page, off, - cmd->request_bufflen, - cmd->sc_data_direction); + dma_handle =pci_map_single (ha->pdev, + cmd->request_buffer, + cmd->request_bufflen, + cmd->sc_data_direction); sp->saved_dma_handle = dma_handle; *dword_ptr++ =cpu_to_le32 (pci_dma_lo32 (dma_handle));
Christoph,
When pci_map_page was originally introduced it was meant to deprecate pci_map_single, at least thats what my memory tells me.
If pci_map_single is suddenly recommended again we can change it back to that, but I don't really see the gain.
Cheers,
Jes
Quoted 4 lines · Jes Sorensen
Christoph,
When
pci_map_pagewas originally introduced it was meant to deprecatepci_map_single, at least thats what my memory tells me.
No, it's for rather different uses. pci_map_page would be nice to get rid of in favour of pci_map_sg OTOH..
Quoted 2 lines
If
pci_map_singleis suddenly recommended again we can change it back to that, but I don't really see the gain.
it's a micro-speedup by avoiding totally useless address arithmetics. You first convert a buffer to page + offset and then it needs to be converted back, e.g. in include/asm-ia64/dma-mapping.h:
#define dma_map_page(dev, pg, off, size, dir) \
dma_map_single(dev, page_address(pg) + (off), (size), (dir))(pci_map_page is mapped to dma_map_page)
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"Christoph" == Christoph Hellwig <[email protected]> writes:
Christoph> On Fri, Feb 18, 2005 at 04:48:00AM -0500, Jes Sorensen
Quoted 4 lines · Christoph> wrote:
Quoted 4 lines
Christoph,
When
pci_map_pagewas originally introduced it was meant to deprecatepci_map_single, at least thats what my memory tells me.
Christoph> No, it's for rather different uses. pci_map_page would be Christoph> nice to get rid of in favour of pci_map_sg OTOH..
I guess things have changed a bit since it was introduced. Anyway go ahead and push the patch.
Cheers,
Jes