if (unlikely(IS_ERR(page))) {
if (PTR_ERR(page) == -ENODATA) {
/* sparse */
- page = virt_to_page(empty_zero_page);
+ page = ZERO_PAGE(0);
} else {
desc->error = PTR_ERR(page);
goto out;
}
- } else
- BUG_ON(!PageUptodate(page));
+ }
/* If users can be writing to this page using arbitrary
* virtual addresses, take care about potential aliasing
flush_dcache_page(page);
/*
- * Ok, we have the page, and it's up-to-date, so
- * now we can copy it to user space...
+ * Ok, we have the page, so now we can copy it to user space...
*
* The actor routine returns how many bytes were actually used..
* NOTE! This may not be the same as how much of a user buffer
file_accessed(filp);
}
-/*
- * This is the "read()" routine for all filesystems
- * that uses the get_xip_page address space operation.
- */
-static ssize_t
-__xip_file_aio_read(struct kiocb *iocb, const struct iovec *iov,
- unsigned long nr_segs, loff_t *ppos)
-{
- struct file *filp = iocb->ki_filp;
- ssize_t retval;
- unsigned long seg;
- size_t count;
-
- count = 0;
- for (seg = 0; seg < nr_segs; seg++) {
- const struct iovec *iv = &iov[seg];
-
- /*
- * If any segment has a negative length, or the cumulative
- * length ever wraps negative then return -EINVAL.
- */
- count += iv->iov_len;
- if (unlikely((ssize_t)(count|iv->iov_len) < 0))
- return -EINVAL;
- if (access_ok(VERIFY_WRITE, iv->iov_base, iv->iov_len))
- continue;
- if (seg == 0)
- return -EFAULT;
- nr_segs = seg;
- count -= iv->iov_len; /* This segment is no good */
- break;
- }
-
- retval = 0;
- if (count) {
- for (seg = 0; seg < nr_segs; seg++) {
- read_descriptor_t desc;
-
- desc.written = 0;
- desc.arg.buf = iov[seg].iov_base;
- desc.count = iov[seg].iov_len;
- if (desc.count == 0)
- continue;
- desc.error = 0;
- do_xip_mapping_read(filp->f_mapping, &filp->f_ra, filp,
- ppos, &desc, file_read_actor);
- retval += desc.written;
- if (!retval) {
- retval = desc.error;
- break;
- }
- }
- }
- return retval;
-}
-
ssize_t
-xip_file_aio_read(struct kiocb *iocb, char __user *buf, size_t count,
- loff_t pos)
+xip_file_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos)
{
- struct iovec local_iov = { .iov_base = buf, .iov_len = count };
+ read_descriptor_t desc;
- BUG_ON(iocb->ki_pos != pos);
- return __xip_file_aio_read(iocb, &local_iov, 1, &iocb->ki_pos);
-}
-EXPORT_SYMBOL_GPL(xip_file_aio_read);
+ if (!access_ok(VERIFY_WRITE, buf, len))
+ return -EFAULT;
-ssize_t
-xip_file_readv(struct file *filp, const struct iovec *iov,
- unsigned long nr_segs, loff_t *ppos)
-{
- struct kiocb kiocb;
+ desc.written = 0;
+ desc.arg.buf = buf;
+ desc.count = len;
+ desc.error = 0;
- init_sync_kiocb(&kiocb, filp);
- return __xip_file_aio_read(&kiocb, iov, nr_segs, ppos);
+ do_xip_mapping_read(filp->f_mapping, &filp->f_ra, filp,
+ ppos, &desc, file_read_actor);
+
+ if (desc.written)
+ return desc.written;
+ else
+ return desc.error;
}
-EXPORT_SYMBOL_GPL(xip_file_readv);
+EXPORT_SYMBOL_GPL(xip_file_read);
ssize_t
xip_file_sendfile(struct file *in_file, loff_t *ppos,
* xip_write
*
* This function walks all vmas of the address_space and unmaps the
- * empty_zero_page when found at pgoff. Should it go in rmap.c?
+ * ZERO_PAGE when found at pgoff. Should it go in rmap.c?
*/
static void
__xip_unmap (struct address_space * mapping,
unsigned long address;
pte_t *pte;
pte_t pteval;
+ spinlock_t *ptl;
+ struct page *page;
spin_lock(&mapping->i_mmap_lock);
vma_prio_tree_foreach(vma, &iter, &mapping->i_mmap, pgoff, pgoff) {
address = vma->vm_start +
((pgoff - vma->vm_pgoff) << PAGE_SHIFT);
BUG_ON(address < vma->vm_start || address >= vma->vm_end);
- /*
- * We need the page_table_lock to protect us from page faults,
- * munmap, fork, etc...
- */
- pte = page_check_address(virt_to_page(empty_zero_page), mm,
- address);
- if (!IS_ERR(pte)) {
+ page = ZERO_PAGE(address);
+ pte = page_check_address(page, mm, address, &ptl);
+ if (pte) {
/* Nuke the page table entry. */
- flush_cache_page(vma, address, pte_pfn(pte));
+ flush_cache_page(vma, address, pte_pfn(*pte));
pteval = ptep_clear_flush(vma, address, pte);
+ page_remove_rmap(page);
+ dec_mm_counter(mm, file_rss);
BUG_ON(pte_dirty(pteval));
- pte_unmap(pte);
- spin_unlock(&mm->page_table_lock);
+ pte_unmap_unlock(pte, ptl);
+ page_cache_release(page);
}
}
spin_unlock(&mapping->i_mmap_lock);
page = mapping->a_ops->get_xip_page(mapping, pgoff*(PAGE_SIZE/512), 0);
if (!IS_ERR(page)) {
- BUG_ON(!PageUptodate(page));
- return page;
+ goto out;
}
if (PTR_ERR(page) != -ENODATA)
return NULL;
pgoff*(PAGE_SIZE/512), 1);
if (IS_ERR(page))
return NULL;
- BUG_ON(!PageUptodate(page));
/* unmap page at pgoff from all other vmas */
__xip_unmap(mapping, pgoff);
} else {
- /* not shared and writable, use empty_zero_page */
- page = virt_to_page(empty_zero_page);
+ /* not shared and writable, use ZERO_PAGE() */
+ page = ZERO_PAGE(address);
}
+out:
+ page_cache_get(page);
return page;
}
EXPORT_SYMBOL_GPL(xip_file_mmap);
static ssize_t
-do_xip_file_write(struct kiocb *iocb, const struct iovec *iov,
- unsigned long nr_segs, loff_t pos, loff_t *ppos,
- size_t count)
+__xip_file_write(struct file *filp, const char __user *buf,
+ size_t count, loff_t pos, loff_t *ppos)
{
- struct file *file = iocb->ki_filp;
- struct address_space * mapping = file->f_mapping;
+ struct address_space * mapping = filp->f_mapping;
struct address_space_operations *a_ops = mapping->a_ops;
struct inode *inode = mapping->host;
long status = 0;
struct page *page;
size_t bytes;
- const struct iovec *cur_iov = iov; /* current iovec */
- size_t iov_base = 0; /* offset in the current iovec */
- char __user *buf;
ssize_t written = 0;
BUG_ON(!mapping->a_ops->get_xip_page);
- buf = iov->iov_base;
do {
unsigned long index;
unsigned long offset;
fault_in_pages_readable(buf, bytes);
page = a_ops->get_xip_page(mapping,
- index*(PAGE_SIZE/512), 0);
+ index*(PAGE_SIZE/512), 0);
if (IS_ERR(page) && (PTR_ERR(page) == -ENODATA)) {
/* we allocate a new page unmap it */
page = a_ops->get_xip_page(mapping,
- index*(PAGE_SIZE/512), 1);
+ index*(PAGE_SIZE/512), 1);
if (!IS_ERR(page))
- /* unmap page at pgoff from all other vmas */
- __xip_unmap(mapping, index);
-
+ /* unmap page at pgoff from all other vmas */
+ __xip_unmap(mapping, index);
}
if (IS_ERR(page)) {
break;
}
- BUG_ON(!PageUptodate(page));
-
- if (likely(nr_segs == 1))
- copied = filemap_copy_from_user(page, offset,
- buf, bytes);
- else
- copied = filemap_copy_from_user_iovec(page, offset,
- cur_iov, iov_base, bytes);
+ copied = filemap_copy_from_user(page, offset, buf, bytes);
flush_dcache_page(page);
if (likely(copied > 0)) {
status = copied;
count -= status;
pos += status;
buf += status;
- if (unlikely(nr_segs > 1))
- filemap_set_next_iovec(&cur_iov,
- &iov_base, status);
}
}
if (unlikely(copied != bytes))
*ppos = pos;
/*
* No need to use i_size_read() here, the i_size
- * cannot change under us because we hold i_sem.
+ * cannot change under us because we hold i_mutex.
*/
if (pos > inode->i_size) {
i_size_write(inode, pos);
return written ? written : status;
}
-static ssize_t
-xip_file_aio_write_nolock(struct kiocb *iocb, const struct iovec *iov,
- unsigned long nr_segs, loff_t *ppos)
+ssize_t
+xip_file_write(struct file *filp, const char __user *buf, size_t len,
+ loff_t *ppos)
{
- struct file *file = iocb->ki_filp;
- struct address_space * mapping = file->f_mapping;
- size_t ocount; /* original count */
- size_t count; /* after file limit checks */
- struct inode *inode = mapping->host;
- unsigned long seg;
- loff_t pos;
- ssize_t written;
- ssize_t err;
+ struct address_space *mapping = filp->f_mapping;
+ struct inode *inode = mapping->host;
+ size_t count;
+ loff_t pos;
+ ssize_t ret;
- ocount = 0;
- for (seg = 0; seg < nr_segs; seg++) {
- const struct iovec *iv = &iov[seg];
+ mutex_lock(&inode->i_mutex);
- /*
- * If any segment has a negative length, or the cumulative
- * length ever wraps negative then return -EINVAL.
- */
- ocount += iv->iov_len;
- if (unlikely((ssize_t)(ocount|iv->iov_len) < 0))
- return -EINVAL;
- if (access_ok(VERIFY_READ, iv->iov_base, iv->iov_len))
- continue;
- if (seg == 0)
- return -EFAULT;
- nr_segs = seg;
- ocount -= iv->iov_len; /* This segment is no good */
- break;
+ if (!access_ok(VERIFY_READ, buf, len)) {
+ ret=-EFAULT;
+ goto out_up;
}
- count = ocount;
pos = *ppos;
+ count = len;
vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE);
- written = 0;
-
- err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
- if (err)
- goto out;
+ /* We can write back this queue in page reclaim */
+ current->backing_dev_info = mapping->backing_dev_info;
+ ret = generic_write_checks(filp, &pos, &count, S_ISBLK(inode->i_mode));
+ if (ret)
+ goto out_backing;
if (count == 0)
- goto out;
+ goto out_backing;
- err = remove_suid(file->f_dentry);
- if (err)
- goto out;
+ ret = remove_suid(filp->f_dentry);
+ if (ret)
+ goto out_backing;
- inode_update_time(inode, 1);
+ file_update_time(filp);
- /* use execute in place to copy directly to disk */
- written = do_xip_file_write (iocb, iov,
- nr_segs, pos, ppos, count);
- out:
- return written ? written : err;
-}
+ ret = __xip_file_write (filp, buf, count, pos, ppos);
-static ssize_t
-__xip_file_write_nolock(struct file *file, const struct iovec *iov,
- unsigned long nr_segs, loff_t *ppos)
-{
- struct kiocb kiocb;
-
- init_sync_kiocb(&kiocb, file);
- return xip_file_aio_write_nolock(&kiocb, iov, nr_segs, ppos);
-}
-
-ssize_t
-xip_file_aio_write(struct kiocb *iocb, const char __user *buf,
- size_t count, loff_t pos)
-{
- struct file *file = iocb->ki_filp;
- struct address_space *mapping = file->f_mapping;
- struct inode *inode = mapping->host;
- ssize_t ret;
- struct iovec local_iov = { .iov_base = (void __user *)buf,
- .iov_len = count };
-
- BUG_ON(iocb->ki_pos != pos);
-
- down(&inode->i_sem);
- ret = xip_file_aio_write_nolock(iocb, &local_iov, 1, &iocb->ki_pos);
- up(&inode->i_sem);
- return ret;
-}
-EXPORT_SYMBOL_GPL(xip_file_aio_write);
-
-ssize_t xip_file_writev(struct file *file, const struct iovec *iov,
- unsigned long nr_segs, loff_t *ppos)
-{
- struct address_space *mapping = file->f_mapping;
- struct inode *inode = mapping->host;
- ssize_t ret;
-
- down(&inode->i_sem);
- ret = __xip_file_write_nolock(file, iov, nr_segs, ppos);
- up(&inode->i_sem);
+ out_backing:
+ current->backing_dev_info = NULL;
+ out_up:
+ mutex_unlock(&inode->i_mutex);
return ret;
}
-EXPORT_SYMBOL_GPL(xip_file_writev);
+EXPORT_SYMBOL_GPL(xip_file_write);
/*
* truncate a page used for execute in place
unsigned length;
struct page *page;
void *kaddr;
- int err;
BUG_ON(!mapping->a_ops->get_xip_page);
page = mapping->a_ops->get_xip_page(mapping,
index*(PAGE_SIZE/512), 0);
- err = -ENOMEM;
if (!page)
- goto out;
+ return -ENOMEM;
if (unlikely(IS_ERR(page))) {
- if (PTR_ERR(page) == -ENODATA) {
+ if (PTR_ERR(page) == -ENODATA)
/* Hole? No need to truncate */
return 0;
- } else {
- err = PTR_ERR(page);
- goto out;
- }
- } else
- BUG_ON(!PageUptodate(page));
+ else
+ return PTR_ERR(page);
+ }
kaddr = kmap_atomic(page, KM_USER0);
memset(kaddr + offset, 0, length);
kunmap_atomic(kaddr, KM_USER0);
flush_dcache_page(page);
- err = 0;
-out:
- return err;
+ return 0;
}
EXPORT_SYMBOL_GPL(xip_truncate_page);