diff options
Diffstat (limited to 'fs/sysfs/bin.c')
| -rw-r--r-- | fs/sysfs/bin.c | 184 |
1 files changed, 171 insertions, 13 deletions
diff --git a/fs/sysfs/bin.c b/fs/sysfs/bin.c index f2c478c3424..96cc2bf6a84 100644 --- a/fs/sysfs/bin.c +++ b/fs/sysfs/bin.c @@ -21,15 +21,28 @@ #include <linux/module.h> #include <linux/slab.h> #include <linux/mutex.h> +#include <linux/mm.h> #include <asm/uaccess.h> #include "sysfs.h" +/* + * There's one bin_buffer for each open file. + * + * filp->private_data points to bin_buffer and + * sysfs_dirent->s_bin_attr.buffers points to a the bin_buffer s + * sysfs_dirent->s_bin_attr.buffers is protected by sysfs_bin_lock + */ +static DEFINE_MUTEX(sysfs_bin_lock); + struct bin_buffer { - struct mutex mutex; - void *buffer; - int mmapped; + struct mutex mutex; + void *buffer; + int mmapped; + struct vm_operations_struct *vm_ops; + struct file *file; + struct hlist_node list; }; static int @@ -168,29 +181,148 @@ out_free: return count; } +static void bin_vma_open(struct vm_area_struct *vma) +{ + struct file *file = vma->vm_file; + struct bin_buffer *bb = file->private_data; + struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata; + + if (!bb->vm_ops || !bb->vm_ops->open) + return; + + if (!sysfs_get_active_two(attr_sd)) + return; + + bb->vm_ops->open(vma); + + sysfs_put_active_two(attr_sd); +} + +static void bin_vma_close(struct vm_area_struct *vma) +{ + struct file *file = vma->vm_file; + struct bin_buffer *bb = file->private_data; + struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata; + + if (!bb->vm_ops || !bb->vm_ops->close) + return; + + if (!sysfs_get_active_two(attr_sd)) + return; + + bb->vm_ops->close(vma); + + sysfs_put_active_two(attr_sd); +} + +static int bin_fault(struct vm_area_struct *vma, struct vm_fault *vmf) +{ + struct file *file = vma->vm_file; + struct bin_buffer *bb = file->private_data; + struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata; + int ret; + + if (!bb->vm_ops || !bb->vm_ops->fault) + return VM_FAULT_SIGBUS; + + if (!sysfs_get_active_two(attr_sd)) + return VM_FAULT_SIGBUS; + + ret = bb->vm_ops->fault(vma, vmf); + + sysfs_put_active_two(attr_sd); + return ret; +} + +static int bin_page_mkwrite(struct vm_area_struct *vma, struct page *page) +{ + struct file *file = vma->vm_file; + struct bin_buffer *bb = file->private_data; + struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata; + int ret; + + if (!bb->vm_ops || !bb->vm_ops->page_mkwrite) + return -EINVAL; + + if (!sysfs_get_active_two(attr_sd)) + return -EINVAL; + + ret = bb->vm_ops->page_mkwrite(vma, page); + + sysfs_put_active_two(attr_sd); + return ret; +} + +static int bin_access(struct vm_area_struct *vma, unsigned long addr, + void *buf, int len, int write) +{ + struct file *file = vma->vm_file; + struct bin_buffer *bb = file->private_data; + struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata; + int ret; + + if (!bb->vm_ops || !bb->vm_ops->access) + return -EINVAL; + + if (!sysfs_get_active_two(attr_sd)) + return -EINVAL; + + ret = bb->vm_ops->access(vma, addr, buf, len, write); + + sysfs_put_active_two(attr_sd); + return ret; +} + +static struct vm_operations_struct bin_vm_ops = { + .open = bin_vma_open, + .close = bin_vma_close, + .fault = bin_fault, + .page_mkwrite = bin_page_mkwrite, + .access = bin_access, +}; + static int mmap(struct file *file, struct vm_area_struct *vma) { struct bin_buffer *bb = file->private_data; struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata; struct bin_attribute *attr = attr_sd->s_bin_attr.bin_attr; struct kobject *kobj = attr_sd->s_parent->s_dir.kobj; + struct vm_operations_struct *vm_ops; int rc; mutex_lock(&bb->mutex); /* need attr_sd for attr, its parent for kobj */ + rc = -ENODEV; if (!sysfs_get_active_two(attr_sd)) - return -ENODEV; + goto out_unlock; rc = -EINVAL; - if (attr->mmap) - rc = attr->mmap(kobj, attr, vma); + if (!attr->mmap) + goto out_put; - if (rc == 0 && !bb->mmapped) - bb->mmapped = 1; - else - sysfs_put_active_two(attr_sd); + rc = attr->mmap(kobj, attr, vma); + vm_ops = vma->vm_ops; + vma->vm_ops = &bin_vm_ops; + if (rc) + goto out_put; + rc = -EINVAL; + if (bb->mmapped && bb->vm_ops != vma->vm_ops) + goto out_put; + +#ifdef CONFIG_NUMA + rc = -EINVAL; + if (vm_ops && ((vm_ops->set_policy || vm_ops->get_policy || vm_ops->migrate))) + goto out_put; +#endif + + rc = 0; + bb->mmapped = 1; + bb->vm_ops = vm_ops; +out_put: + sysfs_put_active_two(attr_sd); +out_unlock: mutex_unlock(&bb->mutex); return rc; @@ -223,8 +355,13 @@ static int open(struct inode * inode, struct file * file) goto err_out; mutex_init(&bb->mutex); + bb->file = file; file->private_data = bb; + mutex_lock(&sysfs_bin_lock); + hlist_add_head(&bb->list, &attr_sd->s_bin_attr.buffers); + mutex_unlock(&sysfs_bin_lock); + /* open succeeded, put active references */ sysfs_put_active_two(attr_sd); return 0; @@ -237,11 +374,12 @@ static int open(struct inode * inode, struct file * file) static int release(struct inode * inode, struct file * file) { - struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata; struct bin_buffer *bb = file->private_data; - if (bb->mmapped) - sysfs_put_active_two(attr_sd); + mutex_lock(&sysfs_bin_lock); + hlist_del(&bb->list); + mutex_unlock(&sysfs_bin_lock); + kfree(bb->buffer); kfree(bb); return 0; @@ -256,6 +394,26 @@ const struct file_operations bin_fops = { .release = release, }; + +void unmap_bin_file(struct sysfs_dirent *attr_sd) +{ + struct bin_buffer *bb; + struct hlist_node *tmp; + + if (sysfs_type(attr_sd) != SYSFS_KOBJ_BIN_ATTR) + return; + + mutex_lock(&sysfs_bin_lock); + + hlist_for_each_entry(bb, tmp, &attr_sd->s_bin_attr.buffers, list) { + struct inode *inode = bb->file->f_path.dentry->d_inode; + + unmap_mapping_range(inode->i_mapping, 0, 0, 1); + } + + mutex_unlock(&sysfs_bin_lock); +} + /** * sysfs_create_bin_file - create binary file for object. * @kobj: object. |