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Date: Fri, 04 Sep 2009 12:26:40 -0700
From: ebiederm@...ssion.com (Eric W. Biederman)
To: Andrew Morton <akpm@...ux-foundation.org>
Cc: <linux-mm@...ck.org>, <linux-kernel@...r.kernel.org>,
<linux-fsdevel@...r.kernel.org>,
Alexey Dobriyan <adobriyan@...il.com>,
Greg Kroah-Hartman <gregkh@...e.de>, Tejun Heo <tj@...nel.org>
Subject: [PATCH 2/4] sysfs: Use revoke_file_mappings
Now that we have a generic helper simply sysfs by using it.
This requires a bit of a logic change because revoke_file_mappings
does proper clean up of the vmas which means it will call
fput which can call release, which grabs sysfs_bin_lock. So I remove
each bin_buffer from the list and drop sysfs_bin_lock before calling
revoke_file_mappings.
Signed-off-by: Eric W. Biederman <ebiederm@...stanetworks.com>
---
fs/sysfs/bin.c | 210 ++++----------------------------------------------------
1 files changed, 13 insertions(+), 197 deletions(-)
diff --git a/fs/sysfs/bin.c b/fs/sysfs/bin.c
index 2524714..530459f 100644
--- a/fs/sysfs/bin.c
+++ b/fs/sysfs/bin.c
@@ -39,8 +39,6 @@ static DEFINE_MUTEX(sysfs_bin_lock);
struct bin_buffer {
struct mutex mutex;
void *buffer;
- int mmapped;
- struct vm_operations_struct *vm_ops;
struct file *file;
struct hlist_node list;
};
@@ -175,175 +173,6 @@ static ssize_t write(struct file *file, const char __user *userbuf,
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 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)
- return VM_FAULT_SIGBUS;
-
- if (!bb->vm_ops->page_mkwrite)
- return 0;
-
- if (!sysfs_get_active_two(attr_sd))
- return VM_FAULT_SIGBUS;
-
- ret = bb->vm_ops->page_mkwrite(vma, vmf);
-
- 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;
-}
-
-#ifdef CONFIG_NUMA
-static int bin_set_policy(struct vm_area_struct *vma, struct mempolicy *new)
-{
- 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->set_policy)
- return 0;
-
- if (!sysfs_get_active_two(attr_sd))
- return -EINVAL;
-
- ret = bb->vm_ops->set_policy(vma, new);
-
- sysfs_put_active_two(attr_sd);
- return ret;
-}
-
-static struct mempolicy *bin_get_policy(struct vm_area_struct *vma,
- unsigned long addr)
-{
- struct file *file = vma->vm_file;
- struct bin_buffer *bb = file->private_data;
- struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
- struct mempolicy *pol;
-
- if (!bb->vm_ops || !bb->vm_ops->get_policy)
- return vma->vm_policy;
-
- if (!sysfs_get_active_two(attr_sd))
- return vma->vm_policy;
-
- pol = bb->vm_ops->get_policy(vma, addr);
-
- sysfs_put_active_two(attr_sd);
- return pol;
-}
-
-static int 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 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->migrate)
- return 0;
-
- if (!sysfs_get_active_two(attr_sd))
- return 0;
-
- ret = bb->vm_ops->migrate(vma, from, to, flags);
-
- sysfs_put_active_two(attr_sd);
- return ret;
-}
-#endif
-
-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,
-#ifdef CONFIG_NUMA
- .set_policy = bin_set_policy,
- .get_policy = bin_get_policy,
- .migrate = bin_migrate,
-#endif
-};
-
static int mmap(struct file *file, struct vm_area_struct *vma)
{
struct bin_buffer *bb = file->private_data;
@@ -367,22 +196,7 @@ static int mmap(struct file *file, struct vm_area_struct *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 (bb->mmapped && bb->vm_ops != vma->vm_ops)
- goto out_put;
-
rc = 0;
- bb->mmapped = 1;
- bb->vm_ops = vma->vm_ops;
- vma->vm_ops = &bin_vm_ops;
out_put:
sysfs_put_active_two(attr_sd);
out_unlock:
@@ -440,7 +254,7 @@ static int release(struct inode * inode, struct file * file)
struct bin_buffer *bb = file->private_data;
mutex_lock(&sysfs_bin_lock);
- hlist_del(&bb->list);
+ hlist_del_init(&bb->list);
mutex_unlock(&sysfs_bin_lock);
kfree(bb->buffer);
@@ -461,20 +275,22 @@ const struct file_operations bin_fops = {
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);
+ do {
+ bb = NULL;
+ mutex_lock(&sysfs_bin_lock);
+ if (!hlist_empty(&attr_sd->s_bin_attr.buffers)) {
+ bb = hlist_entry(attr_sd->s_bin_attr.buffers.first,
+ struct bin_buffer, list);
+ hlist_del_init(&bb->list);
+ }
+ mutex_unlock(&sysfs_bin_lock);
+ if (bb)
+ revoke_file_mappings(bb->file);
+ } while (bb);
}
/**
--
1.6.2.5
--
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