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-rw-r--r--fs/libfs.c46
1 files changed, 27 insertions, 19 deletions
diff --git a/fs/libfs.c b/fs/libfs.c
index 6e68b700958d..b004dfadd891 100644
--- a/fs/libfs.c
+++ b/fs/libfs.c
@@ -341,13 +341,10 @@ int simple_prepare_write(struct file *file, struct page *page,
341 unsigned from, unsigned to) 341 unsigned from, unsigned to)
342{ 342{
343 if (!PageUptodate(page)) { 343 if (!PageUptodate(page)) {
344 if (to - from != PAGE_CACHE_SIZE) { 344 if (to - from != PAGE_CACHE_SIZE)
345 void *kaddr = kmap_atomic(page, KM_USER0); 345 zero_user_segments(page,
346 memset(kaddr, 0, from); 346 0, from,
347 memset(kaddr + to, 0, PAGE_CACHE_SIZE - to); 347 to, PAGE_CACHE_SIZE);
348 flush_dcache_page(page);
349 kunmap_atomic(kaddr, KM_USER0);
350 }
351 } 348 }
352 return 0; 349 return 0;
353} 350}
@@ -586,8 +583,8 @@ int simple_transaction_release(struct inode *inode, struct file *file)
586/* Simple attribute files */ 583/* Simple attribute files */
587 584
588struct simple_attr { 585struct simple_attr {
589 u64 (*get)(void *); 586 int (*get)(void *, u64 *);
590 void (*set)(void *, u64); 587 int (*set)(void *, u64);
591 char get_buf[24]; /* enough to store a u64 and "\n\0" */ 588 char get_buf[24]; /* enough to store a u64 and "\n\0" */
592 char set_buf[24]; 589 char set_buf[24];
593 void *data; 590 void *data;
@@ -598,7 +595,7 @@ struct simple_attr {
598/* simple_attr_open is called by an actual attribute open file operation 595/* simple_attr_open is called by an actual attribute open file operation
599 * to set the attribute specific access operations. */ 596 * to set the attribute specific access operations. */
600int simple_attr_open(struct inode *inode, struct file *file, 597int simple_attr_open(struct inode *inode, struct file *file,
601 u64 (*get)(void *), void (*set)(void *, u64), 598 int (*get)(void *, u64 *), int (*set)(void *, u64),
602 const char *fmt) 599 const char *fmt)
603{ 600{
604 struct simple_attr *attr; 601 struct simple_attr *attr;
@@ -618,7 +615,7 @@ int simple_attr_open(struct inode *inode, struct file *file,
618 return nonseekable_open(inode, file); 615 return nonseekable_open(inode, file);
619} 616}
620 617
621int simple_attr_close(struct inode *inode, struct file *file) 618int simple_attr_release(struct inode *inode, struct file *file)
622{ 619{
623 kfree(file->private_data); 620 kfree(file->private_data);
624 return 0; 621 return 0;
@@ -637,15 +634,24 @@ ssize_t simple_attr_read(struct file *file, char __user *buf,
637 if (!attr->get) 634 if (!attr->get)
638 return -EACCES; 635 return -EACCES;
639 636
640 mutex_lock(&attr->mutex); 637 ret = mutex_lock_interruptible(&attr->mutex);
641 if (*ppos) /* continued read */ 638 if (ret)
639 return ret;
640
641 if (*ppos) { /* continued read */
642 size = strlen(attr->get_buf); 642 size = strlen(attr->get_buf);
643 else /* first read */ 643 } else { /* first read */
644 u64 val;
645 ret = attr->get(attr->data, &val);
646 if (ret)
647 goto out;
648
644 size = scnprintf(attr->get_buf, sizeof(attr->get_buf), 649 size = scnprintf(attr->get_buf, sizeof(attr->get_buf),
645 attr->fmt, 650 attr->fmt, (unsigned long long)val);
646 (unsigned long long)attr->get(attr->data)); 651 }
647 652
648 ret = simple_read_from_buffer(buf, len, ppos, attr->get_buf, size); 653 ret = simple_read_from_buffer(buf, len, ppos, attr->get_buf, size);
654out:
649 mutex_unlock(&attr->mutex); 655 mutex_unlock(&attr->mutex);
650 return ret; 656 return ret;
651} 657}
@@ -660,11 +666,13 @@ ssize_t simple_attr_write(struct file *file, const char __user *buf,
660 ssize_t ret; 666 ssize_t ret;
661 667
662 attr = file->private_data; 668 attr = file->private_data;
663
664 if (!attr->set) 669 if (!attr->set)
665 return -EACCES; 670 return -EACCES;
666 671
667 mutex_lock(&attr->mutex); 672 ret = mutex_lock_interruptible(&attr->mutex);
673 if (ret)
674 return ret;
675
668 ret = -EFAULT; 676 ret = -EFAULT;
669 size = min(sizeof(attr->set_buf) - 1, len); 677 size = min(sizeof(attr->set_buf) - 1, len);
670 if (copy_from_user(attr->set_buf, buf, size)) 678 if (copy_from_user(attr->set_buf, buf, size))
@@ -796,6 +804,6 @@ EXPORT_SYMBOL(simple_transaction_get);
796EXPORT_SYMBOL(simple_transaction_read); 804EXPORT_SYMBOL(simple_transaction_read);
797EXPORT_SYMBOL(simple_transaction_release); 805EXPORT_SYMBOL(simple_transaction_release);
798EXPORT_SYMBOL_GPL(simple_attr_open); 806EXPORT_SYMBOL_GPL(simple_attr_open);
799EXPORT_SYMBOL_GPL(simple_attr_close); 807EXPORT_SYMBOL_GPL(simple_attr_release);
800EXPORT_SYMBOL_GPL(simple_attr_read); 808EXPORT_SYMBOL_GPL(simple_attr_read);
801EXPORT_SYMBOL_GPL(simple_attr_write); 809EXPORT_SYMBOL_GPL(simple_attr_write);