#include <linux/limits.h>
#include <linux/uaccess.h>
#include <linux/seq_file.h>
+#include <linux/mm.h>
#include "sysfs.h"
struct mutex mutex;
int event;
struct list_head list;
+
+ bool mmapped;
+ const struct vm_operations_struct *vm_ops;
};
static bool sysfs_is_bin(struct sysfs_dirent *sd)
{
struct kobject *kobj = sd->s_parent->s_dir.kobj;
- lockdep_assert_held(sd);
+ if (!sysfs_ignore_lockdep(sd))
+ lockdep_assert_held(sd);
return kobj->ktype ? kobj->ktype->sysfs_ops : NULL;
}
return 0;
}
+/*
+ * Read method for bin files. As reading a bin file can have side-effects,
+ * the exact offset and bytes specified in read(2) call should be passed to
+ * the read callback making it difficult to use seq_file. Implement
+ * simplistic custom buffering for bin files.
+ */
+static ssize_t sysfs_bin_read(struct file *file, char __user *userbuf,
+ size_t bytes, loff_t *off)
+{
+ struct sysfs_open_file *of = sysfs_of(file);
+ struct bin_attribute *battr = of->sd->s_bin_attr.bin_attr;
+ struct kobject *kobj = of->sd->s_parent->s_dir.kobj;
+ loff_t size = file_inode(file)->i_size;
+ int count = min_t(size_t, bytes, PAGE_SIZE);
+ loff_t offs = *off;
+ char *buf;
+
+ if (!bytes)
+ return 0;
+
+ if (size) {
+ if (offs > size)
+ return 0;
+ if (offs + count > size)
+ count = size - offs;
+ }
+
+ buf = kmalloc(count, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ /* need of->sd for battr, its parent for kobj */
+ mutex_lock(&of->mutex);
+ if (!sysfs_get_active(of->sd)) {
+ count = -ENODEV;
+ mutex_unlock(&of->mutex);
+ goto out_free;
+ }
+
+ if (battr->read)
+ count = battr->read(file, kobj, battr, buf, offs, count);
+ else
+ count = -EIO;
+
+ sysfs_put_active(of->sd);
+ mutex_unlock(&of->mutex);
+
+ if (count < 0)
+ goto out_free;
+
+ if (copy_to_user(userbuf, buf, count)) {
+ count = -EFAULT;
+ goto out_free;
+ }
+
+ pr_debug("offs = %lld, *off = %lld, count = %d\n", offs, *off, count);
+
+ *off = offs + count;
+
+ out_free:
+ kfree(buf);
+ return count;
+}
+
/**
* flush_write_buffer - push buffer to kobject
* @of: open file
return len;
}
+static void sysfs_bin_vma_open(struct vm_area_struct *vma)
+{
+ struct file *file = vma->vm_file;
+ struct sysfs_open_file *of = sysfs_of(file);
+
+ if (!of->vm_ops)
+ return;
+
+ if (!sysfs_get_active(of->sd))
+ return;
+
+ if (of->vm_ops->open)
+ of->vm_ops->open(vma);
+
+ sysfs_put_active(of->sd);
+}
+
+static int sysfs_bin_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
+{
+ struct file *file = vma->vm_file;
+ struct sysfs_open_file *of = sysfs_of(file);
+ int ret;
+
+ if (!of->vm_ops)
+ return VM_FAULT_SIGBUS;
+
+ if (!sysfs_get_active(of->sd))
+ return VM_FAULT_SIGBUS;
+
+ ret = VM_FAULT_SIGBUS;
+ if (of->vm_ops->fault)
+ ret = of->vm_ops->fault(vma, vmf);
+
+ sysfs_put_active(of->sd);
+ return ret;
+}
+
+static int sysfs_bin_page_mkwrite(struct vm_area_struct *vma,
+ struct vm_fault *vmf)
+{
+ struct file *file = vma->vm_file;
+ struct sysfs_open_file *of = sysfs_of(file);
+ int ret;
+
+ if (!of->vm_ops)
+ return VM_FAULT_SIGBUS;
+
+ if (!sysfs_get_active(of->sd))
+ return VM_FAULT_SIGBUS;
+
+ ret = 0;
+ if (of->vm_ops->page_mkwrite)
+ ret = of->vm_ops->page_mkwrite(vma, vmf);
+ else
+ file_update_time(file);
+
+ sysfs_put_active(of->sd);
+ return ret;
+}
+
+static int sysfs_bin_access(struct vm_area_struct *vma, unsigned long addr,
+ void *buf, int len, int write)
+{
+ struct file *file = vma->vm_file;
+ struct sysfs_open_file *of = sysfs_of(file);
+ int ret;
+
+ if (!of->vm_ops)
+ return -EINVAL;
+
+ if (!sysfs_get_active(of->sd))
+ return -EINVAL;
+
+ ret = -EINVAL;
+ if (of->vm_ops->access)
+ ret = of->vm_ops->access(vma, addr, buf, len, write);
+
+ sysfs_put_active(of->sd);
+ return ret;
+}
+
+#ifdef CONFIG_NUMA
+static int sysfs_bin_set_policy(struct vm_area_struct *vma,
+ struct mempolicy *new)
+{
+ struct file *file = vma->vm_file;
+ struct sysfs_open_file *of = sysfs_of(file);
+ int ret;
+
+ if (!of->vm_ops)
+ return 0;
+
+ if (!sysfs_get_active(of->sd))
+ return -EINVAL;
+
+ ret = 0;
+ if (of->vm_ops->set_policy)
+ ret = of->vm_ops->set_policy(vma, new);
+
+ sysfs_put_active(of->sd);
+ return ret;
+}
+
+static struct mempolicy *sysfs_bin_get_policy(struct vm_area_struct *vma,
+ unsigned long addr)
+{
+ struct file *file = vma->vm_file;
+ struct sysfs_open_file *of = sysfs_of(file);
+ struct mempolicy *pol;
+
+ if (!of->vm_ops)
+ return vma->vm_policy;
+
+ if (!sysfs_get_active(of->sd))
+ return vma->vm_policy;
+
+ pol = vma->vm_policy;
+ if (of->vm_ops->get_policy)
+ pol = of->vm_ops->get_policy(vma, addr);
+
+ sysfs_put_active(of->sd);
+ return pol;
+}
+
+static int sysfs_bin_migrate(struct vm_area_struct *vma, const nodemask_t *from,
+ const nodemask_t *to, unsigned long flags)
+{
+ struct file *file = vma->vm_file;
+ struct sysfs_open_file *of = sysfs_of(file);
+ int ret;
+
+ if (!of->vm_ops)
+ return 0;
+
+ if (!sysfs_get_active(of->sd))
+ return 0;
+
+ ret = 0;
+ if (of->vm_ops->migrate)
+ ret = of->vm_ops->migrate(vma, from, to, flags);
+
+ sysfs_put_active(of->sd);
+ return ret;
+}
+#endif
+
+static const struct vm_operations_struct sysfs_bin_vm_ops = {
+ .open = sysfs_bin_vma_open,
+ .fault = sysfs_bin_fault,
+ .page_mkwrite = sysfs_bin_page_mkwrite,
+ .access = sysfs_bin_access,
+#ifdef CONFIG_NUMA
+ .set_policy = sysfs_bin_set_policy,
+ .get_policy = sysfs_bin_get_policy,
+ .migrate = sysfs_bin_migrate,
+#endif
+};
+
+static int sysfs_bin_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ struct sysfs_open_file *of = sysfs_of(file);
+ struct bin_attribute *battr = of->sd->s_bin_attr.bin_attr;
+ struct kobject *kobj = of->sd->s_parent->s_dir.kobj;
+ int rc;
+
+ mutex_lock(&of->mutex);
+
+ /* need of->sd for battr, its parent for kobj */
+ rc = -ENODEV;
+ if (!sysfs_get_active(of->sd))
+ goto out_unlock;
+
+ rc = -EINVAL;
+ if (!battr->mmap)
+ goto out_put;
+
+ rc = battr->mmap(file, kobj, battr, vma);
+ if (rc)
+ goto out_put;
+
+ /*
+ * PowerPC's pci_mmap of legacy_mem uses shmem_zero_setup()
+ * to satisfy versions of X which crash if the mmap fails: that
+ * substitutes a new vm_file, and we don't then want bin_vm_ops.
+ */
+ if (vma->vm_file != file)
+ goto out_put;
+
+ rc = -EINVAL;
+ if (of->mmapped && of->vm_ops != vma->vm_ops)
+ goto out_put;
+
+ /*
+ * It is not possible to successfully wrap close.
+ * So error if someone is trying to use close.
+ */
+ rc = -EINVAL;
+ if (vma->vm_ops && vma->vm_ops->close)
+ goto out_put;
+
+ rc = 0;
+ of->mmapped = 1;
+ of->vm_ops = vma->vm_ops;
+ vma->vm_ops = &sysfs_bin_vm_ops;
+out_put:
+ sysfs_put_active(of->sd);
+out_unlock:
+ mutex_unlock(&of->mutex);
+
+ return rc;
+}
+
/**
* sysfs_get_open_dirent - get or create sysfs_open_dirent
* @sd: target sysfs_dirent
mutex_lock(&sysfs_open_file_mutex);
spin_lock_irqsave(&sysfs_open_dirent_lock, flags);
- list_del(&of->list);
+ if (of)
+ list_del(&of->list);
+
if (atomic_dec_and_test(&od->refcnt))
sd->s_attr.open = NULL;
else
struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
struct kobject *kobj = attr_sd->s_parent->s_dir.kobj;
struct sysfs_open_file *of;
- const struct sysfs_ops *ops;
+ bool has_read, has_write;
int error = -EACCES;
/* need attr_sd for attr and ops, its parent for kobj */
if (!sysfs_get_active(attr_sd))
return -ENODEV;
- /* every kobject with an attribute needs a ktype assigned */
- ops = sysfs_file_ops(attr_sd);
- if (WARN(!ops, KERN_ERR
- "missing sysfs attribute operations for kobject: %s\n",
- kobject_name(kobj)))
- goto err_out;
+ if (sysfs_is_bin(attr_sd)) {
+ struct bin_attribute *battr = attr_sd->s_bin_attr.bin_attr;
- /* File needs write support.
- * The inode's perms must say it's ok,
- * and we must have a store method.
- */
- if (file->f_mode & FMODE_WRITE) {
- if (!(inode->i_mode & S_IWUGO) || !ops->store)
- goto err_out;
- }
+ has_read = battr->read || battr->mmap;
+ has_write = battr->write || battr->mmap;
+ } else {
+ const struct sysfs_ops *ops = sysfs_file_ops(attr_sd);
- /* File needs read support.
- * The inode's perms must say it's ok, and we there
- * must be a show method for it.
- */
- if (file->f_mode & FMODE_READ) {
- if (!(inode->i_mode & S_IRUGO) || !ops->show)
+ /* every kobject with an attribute needs a ktype assigned */
+ if (WARN(!ops, KERN_ERR
+ "missing sysfs attribute operations for kobject: %s\n",
+ kobject_name(kobj)))
goto err_out;
+
+ has_read = ops->show;
+ has_write = ops->store;
}
+ /* check perms and supported operations */
+ if ((file->f_mode & FMODE_WRITE) &&
+ (!(inode->i_mode & S_IWUGO) || !has_write))
+ goto err_out;
+
+ if ((file->f_mode & FMODE_READ) &&
+ (!(inode->i_mode & S_IRUGO) || !has_read))
+ goto err_out;
+
/* allocate a sysfs_open_file for the file */
error = -ENOMEM;
of = kzalloc(sizeof(struct sysfs_open_file), GFP_KERNEL);
of->file = file;
/*
- * Always instantiate seq_file even if read access is not
- * implemented or requested. This unifies private data access and
- * most files are readable anyway.
+ * Always instantiate seq_file even if read access doesn't use
+ * seq_file or is not requested. This unifies private data access
+ * and readable regular files are the vast majority anyway.
*/
- error = single_open(file, sysfs_seq_show, of);
+ if (sysfs_is_bin(attr_sd))
+ error = single_open(file, NULL, of);
+ else
+ error = single_open(file, sysfs_seq_show, of);
if (error)
goto err_free;
return 0;
}
+void sysfs_unmap_bin_file(struct sysfs_dirent *sd)
+{
+ struct sysfs_open_dirent *od;
+ struct sysfs_open_file *of;
+
+ if (!sysfs_is_bin(sd))
+ return;
+
+ spin_lock_irq(&sysfs_open_dirent_lock);
+ od = sd->s_attr.open;
+ if (od)
+ atomic_inc(&od->refcnt);
+ spin_unlock_irq(&sysfs_open_dirent_lock);
+ if (!od)
+ return;
+
+ mutex_lock(&sysfs_open_file_mutex);
+ list_for_each_entry(of, &od->files, list) {
+ struct inode *inode = file_inode(of->file);
+ unmap_mapping_range(inode->i_mapping, 0, 0, 1);
+ }
+ mutex_unlock(&sysfs_open_file_mutex);
+
+ sysfs_put_open_dirent(sd, NULL);
+}
+
/* Sysfs attribute files are pollable. The idea is that you read
* the content and then you use 'poll' or 'select' to wait for
* the content to change. When the content changes (assuming the
};
const struct file_operations sysfs_bin_operations = {
+ .read = sysfs_bin_read,
.write = sysfs_write_file,
.llseek = generic_file_llseek,
+ .mmap = sysfs_bin_mmap,
+ .open = sysfs_open_file,
+ .release = sysfs_release,
+ .poll = sysfs_poll,
};
int sysfs_add_file_mode_ns(struct sysfs_dirent *dir_sd,
}
EXPORT_SYMBOL_GPL(sysfs_remove_file_from_group);
+/**
+ * sysfs_create_bin_file - create binary file for object.
+ * @kobj: object.
+ * @attr: attribute descriptor.
+ */
+int sysfs_create_bin_file(struct kobject *kobj,
+ const struct bin_attribute *attr)
+{
+ BUG_ON(!kobj || !kobj->sd || !attr);
+
+ return sysfs_add_file(kobj->sd, &attr->attr, SYSFS_KOBJ_BIN_ATTR);
+}
+EXPORT_SYMBOL_GPL(sysfs_create_bin_file);
+
+/**
+ * sysfs_remove_bin_file - remove binary file for object.
+ * @kobj: object.
+ * @attr: attribute descriptor.
+ */
+void sysfs_remove_bin_file(struct kobject *kobj,
+ const struct bin_attribute *attr)
+{
+ sysfs_hash_and_remove(kobj->sd, attr->attr.name, NULL);
+}
+EXPORT_SYMBOL_GPL(sysfs_remove_bin_file);
+
struct sysfs_schedule_callback_struct {
struct list_head workq_list;
struct kobject *kobj;
projects / karo-tx-linux.git / blobdiff