From 93bb8e352a9136a56dd26762bf54cf6554cfa96c Mon Sep 17 00:00:00 2001 From: Krzysztof Wilczyński Date: Thu, 29 Jul 2021 23:32:34 +0000 Subject: sysfs: Invoke iomem_get_mapping() from the sysfs open callback MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 Reviewed-by: Dan Williams Acked-by: Bjorn Helgaas Signed-off-by: Dan Williams Signed-off-by: Krzysztof Wilczyński Link: https://lore.kernel.org/r/20210729233235.1508920-2-kw@linux.com Signed-off-by: Greg Kroah-Hartman --- fs/sysfs/file.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs/sysfs') 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; } -- cgit v1.2.3-58-ga151 From f06aff924f975881a6abf91d2af0078fc8cd37bf Mon Sep 17 00:00:00 2001 From: Krzysztof Wilczyński Date: Thu, 29 Jul 2021 23:32:35 +0000 Subject: sysfs: Rename struct bin_attribute member to f_mapping MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit There are two users of iomem_get_mapping(), the struct file and struct bin_attribute. The former has a member called "f_mapping" and the latter has a member called "mapping", and both are poniters to struct address_space. Rename struct bin_attribute member to "f_mapping" to keep both meaning and the usage consistent with other users of iomem_get_mapping(). Acked-by: Bjorn Helgaas Signed-off-by: Krzysztof Wilczyński Link: https://lore.kernel.org/r/20210729233235.1508920-3-kw@linux.com Signed-off-by: Greg Kroah-Hartman --- drivers/pci/pci-sysfs.c | 6 +++--- fs/sysfs/file.c | 4 ++-- include/linux/sysfs.h | 2 +- 3 files changed, 6 insertions(+), 6 deletions(-) (limited to 'fs/sysfs') diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c index 76e5545d0e73..f65382915f01 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->f_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->f_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->f_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 a3ee4c32a264..d019d6ac6ad0 100644 --- a/fs/sysfs/file.c +++ b/fs/sysfs/file.c @@ -174,8 +174,8 @@ 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(); + if (battr->f_mapping) + of->file->f_mapping = battr->f_mapping(); return 0; } diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h index d5bcc897583c..e3f1e8ac1f85 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)(void); + struct address_space *(*f_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 *, -- cgit v1.2.3-58-ga151