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Commit 02a20d4f authored by Christophe JAILLET's avatar Christophe JAILLET Committed by Jakub Kicinski
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enic: switch from 'pci_' to 'dma_' API



The wrappers in include/linux/pci-dma-compat.h should go away.

The patch has been generated with the coccinelle script below and has been
hand modified to replace GFP_ with a correct flag.
It has been compile tested.

When memory is allocated in 'vnic_dev_classifier()', 'vnic_dev_fw_info()',
'vnic_dev_notify_set()' and 'vnic_dev_stats_dump()' (vnic_dev.c) GFP_ATOMIC
must be used because its callers take a spinlock before calling these
functions.

When memory is allocated in '__enic_set_rsskey()' and 'enic_set_rsscpu()'
GFP_ATOMIC must be used because they can be called with a spinlock.
The call chain is:
  enic_reset                         <-- takes 'enic->enic_api_lock'
    --> enic_set_rss_nic_cfg
      --> enic_set_rsskey
        --> __enic_set_rsskey        <-- uses dma_alloc_coherent
      --> enic_set_rsscpu            <-- uses dma_alloc_coherent

When memory is allocated in 'vnic_dev_init_prov2()' GFP_ATOMIC must be used
because a spinlock is hidden in the ENIC_DEVCMD_PROXY_BY_INDEX macro, when
this function is called in 'enic_set_port_profile()'.

When memory is allocated in 'vnic_dev_alloc_desc_ring()' GFP_KERNEL can be
used because it is only called from 5 functions ('vnic_dev_init_devcmd2()',
'vnic_cq_alloc()', 'vnic_rq_alloc()', 'vnic_wq_alloc()' and
'enic_wq_devcmd2_alloc()'.

  'vnic_dev_init_devcmd2()': already uses GFP_KERNEL and no lock is taken
     in the between.
  'enic_wq_devcmd2_alloc()': is called from ' vnic_dev_init_devcmd2()'
     which already uses GFP_KERNEL and no lock is taken in the between.
  'vnic_cq_alloc()', 'vnic_rq_alloc()', 'vnic_wq_alloc()': are called
     from 'enic_alloc_vnic_resources()'
'enic_alloc_vnic_resources()' has only 2 call chains:

  1) enic_probe
      --> enic_dev_init
        --> enic_alloc_vnic_resources
'enic_probe()' is a probe function and no lock is taken in the between

  2) enic_set_ringparam
      --> enic_alloc_vnic_resources
'enic_set_ringparam()' is a .set_ringparam function (see struct
ethtool_ops). It seems to only take a mutex and no spinlock.

So all paths are safe to use GFP_KERNEL.

@@
@@
-    PCI_DMA_BIDIRECTIONAL
+    DMA_BIDIRECTIONAL

@@
@@
-    PCI_DMA_TODEVICE
+    DMA_TO_DEVICE

@@
@@
-    PCI_DMA_FROMDEVICE
+    DMA_FROM_DEVICE

@@
@@
-    PCI_DMA_NONE
+    DMA_NONE

@@
expression e1, e2, e3;
@@
-    pci_alloc_consistent(e1, e2, e3)
+    dma_alloc_coherent(&e1->dev, e2, e3, GFP_)

@@
expression e1, e2, e3;
@@
-    pci_zalloc_consistent(e1, e2, e3)
+    dma_alloc_coherent(&e1->dev, e2, e3, GFP_)

@@
expression e1, e2, e3, e4;
@@
-    pci_free_consistent(e1, e2, e3, e4)
+    dma_free_coherent(&e1->dev, e2, e3, e4)

@@
expression e1, e2, e3, e4;
@@
-    pci_map_single(e1, e2, e3, e4)
+    dma_map_single(&e1->dev, e2, e3, e4)

@@
expression e1, e2, e3, e4;
@@
-    pci_unmap_single(e1, e2, e3, e4)
+    dma_unmap_single(&e1->dev, e2, e3, e4)

@@
expression e1, e2, e3, e4, e5;
@@
-    pci_map_page(e1, e2, e3, e4, e5)
+    dma_map_page(&e1->dev, e2, e3, e4, e5)

@@
expression e1, e2, e3, e4;
@@
-    pci_unmap_page(e1, e2, e3, e4)
+    dma_unmap_page(&e1->dev, e2, e3, e4)

@@
expression e1, e2, e3, e4;
@@
-    pci_map_sg(e1, e2, e3, e4)
+    dma_map_sg(&e1->dev, e2, e3, e4)

@@
expression e1, e2, e3, e4;
@@
-    pci_unmap_sg(e1, e2, e3, e4)
+    dma_unmap_sg(&e1->dev, e2, e3, e4)

@@
expression e1, e2, e3, e4;
@@
-    pci_dma_sync_single_for_cpu(e1, e2, e3, e4)
+    dma_sync_single_for_cpu(&e1->dev, e2, e3, e4)

@@
expression e1, e2, e3, e4;
@@
-    pci_dma_sync_single_for_device(e1, e2, e3, e4)
+    dma_sync_single_for_device(&e1->dev, e2, e3, e4)

@@
expression e1, e2, e3, e4;
@@
-    pci_dma_sync_sg_for_cpu(e1, e2, e3, e4)
+    dma_sync_sg_for_cpu(&e1->dev, e2, e3, e4)

@@
expression e1, e2, e3, e4;
@@
-    pci_dma_sync_sg_for_device(e1, e2, e3, e4)
+    dma_sync_sg_for_device(&e1->dev, e2, e3, e4)

@@
expression e1, e2;
@@
-    pci_dma_mapping_error(e1, e2)
+    dma_mapping_error(&e1->dev, e2)

@@
expression e1, e2;
@@
-    pci_set_dma_mask(e1, e2)
+    dma_set_mask(&e1->dev, e2)

@@
expression e1, e2;
@@
-    pci_set_consistent_dma_mask(e1, e2)
+    dma_set_coherent_mask(&e1->dev, e2)

Signed-off-by: default avatarChristophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 3e813d61
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