Message ID | 20210729233235.1508920-2-kw@linux.com (mailing list archive) |
---|---|
State | Not Applicable |
Delegated to: | Bjorn Helgaas |
Headers | show |
Series | Allow deferred execution of iomem_get_mapping() | expand |
On Thu, Jul 29, 2021 at 11:32:34PM +0000, Krzysztof Wilczyński wrote: > Defer invocation of the iomem_get_mapping() to the sysfs open callback > so that it can be executed as needed when the binary sysfs object has > been accessed. > > To do that, convert the "mapping" member of the struct bin_attribute > from a pointer to the struct address_space into a function pointer with > a signature that requires the same return type, and then updates the > sysfs_kf_bin_open() to invoke provided function should the function > pointer be valid. > > Also, convert every invocation of iomem_get_mapping() into a function > pointer assignment, therefore allowing for the iomem_get_mapping() > invocation to be deferred to when the sysfs open callback runs. > > Thus, this change removes the need for the fs_initcalls to complete > before any other sub-system that uses the iomem_get_mapping() would be > able to invoke it safely without leading to a failure and an Oops > related to an invalid iomem_get_mapping() access. > > Suggested-by: Dan Williams <dan.j.williams@intel.com> > Signed-off-by: Dan Williams <dan.j.williams@intel.com> > Signed-off-by: Krzysztof Wilczyński <kw@linux.com> > Reviewed-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> > --- > drivers/pci/pci-sysfs.c | 6 +++--- > fs/sysfs/file.c | 2 +- > include/linux/sysfs.h | 2 +- > 3 files changed, 5 insertions(+), 5 deletions(-) > > diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c > index 5d63df7c1820..76e5545d0e73 100644 > --- a/drivers/pci/pci-sysfs.c > +++ b/drivers/pci/pci-sysfs.c > @@ -965,7 +965,7 @@ void pci_create_legacy_files(struct pci_bus *b) > b->legacy_io->read = pci_read_legacy_io; > b->legacy_io->write = pci_write_legacy_io; > b->legacy_io->mmap = pci_mmap_legacy_io; > - b->legacy_io->mapping = iomem_get_mapping(); > + b->legacy_io->mapping = iomem_get_mapping; > pci_adjust_legacy_attr(b, pci_mmap_io); > error = device_create_bin_file(&b->dev, b->legacy_io); > if (error) > @@ -978,7 +978,7 @@ void pci_create_legacy_files(struct pci_bus *b) > b->legacy_mem->size = 1024*1024; > b->legacy_mem->attr.mode = 0600; > b->legacy_mem->mmap = pci_mmap_legacy_mem; > - b->legacy_io->mapping = iomem_get_mapping(); > + b->legacy_io->mapping = iomem_get_mapping; > pci_adjust_legacy_attr(b, pci_mmap_mem); > error = device_create_bin_file(&b->dev, b->legacy_mem); > if (error) > @@ -1195,7 +1195,7 @@ static int pci_create_attr(struct pci_dev *pdev, int num, int write_combine) > } > } > if (res_attr->mmap) > - res_attr->mapping = iomem_get_mapping(); > + res_attr->mapping = iomem_get_mapping; > res_attr->attr.name = res_attr_name; > res_attr->attr.mode = 0600; > res_attr->size = pci_resource_len(pdev, num); > diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c > index 9aefa7779b29..a3ee4c32a264 100644 > --- a/fs/sysfs/file.c > +++ b/fs/sysfs/file.c > @@ -175,7 +175,7 @@ static int sysfs_kf_bin_open(struct kernfs_open_file *of) > struct bin_attribute *battr = of->kn->priv; > > if (battr->mapping) > - of->file->f_mapping = battr->mapping; > + of->file->f_mapping = battr->mapping(); > > return 0; > } > diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h > index a12556a4b93a..d5bcc897583c 100644 > --- a/include/linux/sysfs.h > +++ b/include/linux/sysfs.h > @@ -176,7 +176,7 @@ struct bin_attribute { > struct attribute attr; > size_t size; > void *private; > - struct address_space *mapping; > + struct address_space *(*mapping)(void); > ssize_t (*read)(struct file *, struct kobject *, struct bin_attribute *, > char *, loff_t, size_t); > ssize_t (*write)(struct file *, struct kobject *, struct bin_attribute *, > -- > 2.32.0 >
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c index 5d63df7c1820..76e5545d0e73 100644 --- a/drivers/pci/pci-sysfs.c +++ b/drivers/pci/pci-sysfs.c @@ -965,7 +965,7 @@ void pci_create_legacy_files(struct pci_bus *b) b->legacy_io->read = pci_read_legacy_io; b->legacy_io->write = pci_write_legacy_io; b->legacy_io->mmap = pci_mmap_legacy_io; - b->legacy_io->mapping = iomem_get_mapping(); + b->legacy_io->mapping = iomem_get_mapping; pci_adjust_legacy_attr(b, pci_mmap_io); error = device_create_bin_file(&b->dev, b->legacy_io); if (error) @@ -978,7 +978,7 @@ void pci_create_legacy_files(struct pci_bus *b) b->legacy_mem->size = 1024*1024; b->legacy_mem->attr.mode = 0600; b->legacy_mem->mmap = pci_mmap_legacy_mem; - b->legacy_io->mapping = iomem_get_mapping(); + b->legacy_io->mapping = iomem_get_mapping; pci_adjust_legacy_attr(b, pci_mmap_mem); error = device_create_bin_file(&b->dev, b->legacy_mem); if (error) @@ -1195,7 +1195,7 @@ static int pci_create_attr(struct pci_dev *pdev, int num, int write_combine) } } if (res_attr->mmap) - res_attr->mapping = iomem_get_mapping(); + res_attr->mapping = iomem_get_mapping; res_attr->attr.name = res_attr_name; res_attr->attr.mode = 0600; res_attr->size = pci_resource_len(pdev, num); diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c index 9aefa7779b29..a3ee4c32a264 100644 --- a/fs/sysfs/file.c +++ b/fs/sysfs/file.c @@ -175,7 +175,7 @@ static int sysfs_kf_bin_open(struct kernfs_open_file *of) struct bin_attribute *battr = of->kn->priv; if (battr->mapping) - of->file->f_mapping = battr->mapping; + of->file->f_mapping = battr->mapping(); return 0; } diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h index a12556a4b93a..d5bcc897583c 100644 --- a/include/linux/sysfs.h +++ b/include/linux/sysfs.h @@ -176,7 +176,7 @@ struct bin_attribute { struct attribute attr; size_t size; void *private; - struct address_space *mapping; + struct address_space *(*mapping)(void); ssize_t (*read)(struct file *, struct kobject *, struct bin_attribute *, char *, loff_t, size_t); ssize_t (*write)(struct file *, struct kobject *, struct bin_attribute *,