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Merge branch 'splice-2.6.22' of git://git.kernel.dk/data/git/linux-2.6-block

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* 'splice-2.6.22' of git://git.kernel.dk/data/git/linux-2.6-block:
  splice: __generic_file_splice_read: fix read/truncate race
  splice: __generic_file_splice_read: fix i_size_read() length checks
  splice: move balance_dirty_pages_ratelimited() outside of splice actor
  pipe: move pipe_inode_info structure decleration up before it's used
  splice: remove do_splice_direct() symbol export
  splice: move inode size check into generic_file_splice_read()
This commit is contained in:
Linus Torvalds 2007-06-11 11:31:05 -07:00
commit 5212c555be
2 changed files with 50 additions and 50 deletions
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70
fs/splice.c
View File

@ -272,7 +272,6 @@ __generic_file_splice_read(struct file *in, loff_t *ppos,
struct page *page;
pgoff_t index, end_index;
loff_t isize;
size_t total_len;
int error, page_nr;
struct splice_pipe_desc spd = {
.pages = pages,
@ -298,7 +297,6 @@ __generic_file_splice_read(struct file *in, loff_t *ppos,
* Now fill in the holes:
*/
error = 0;
total_len = 0;
/*
* Lookup the (hopefully) full range of pages we need.
@ -415,43 +413,47 @@ __generic_file_splice_read(struct file *in, loff_t *ppos,
break;
}
}
fill_it:
/*
* i_size must be checked after PageUptodate.
*/
isize = i_size_read(mapping->host);
end_index = (isize - 1) >> PAGE_CACHE_SHIFT;
if (unlikely(!isize || index > end_index))
break;
/*
* if this is the last page, see if we need to shrink
* the length and stop
*/
if (end_index == index) {
unsigned int plen;
/*
* i_size must be checked after ->readpage().
* max good bytes in this page
*/
isize = i_size_read(mapping->host);
end_index = (isize - 1) >> PAGE_CACHE_SHIFT;
if (unlikely(!isize || index > end_index))
plen = ((isize - 1) & ~PAGE_CACHE_MASK) + 1;
if (plen <= loff)
break;
/*
* if this is the last page, see if we need to shrink
* the length and stop
* force quit after adding this page
*/
if (end_index == index) {
loff = PAGE_CACHE_SIZE - (isize & ~PAGE_CACHE_MASK);
if (total_len + loff > isize)
break;
/*
* force quit after adding this page
*/
len = this_len;
this_len = min(this_len, loff);
loff = 0;
}
this_len = min(this_len, plen - loff);
len = this_len;
}
fill_it:
partial[page_nr].offset = loff;
partial[page_nr].len = this_len;
len -= this_len;
total_len += this_len;
loff = 0;
spd.nr_pages++;
index++;
}
/*
* Release any pages at the end, if we quit early. 'i' is how far
* Release any pages at the end, if we quit early. 'page_nr' is how far
* we got, 'nr_pages' is how many pages are in the map.
*/
while (page_nr < nr_pages)
@ -478,10 +480,18 @@ ssize_t generic_file_splice_read(struct file *in, loff_t *ppos,
{
ssize_t spliced;
int ret;
loff_t isize, left;
isize = i_size_read(in->f_mapping->host);
if (unlikely(*ppos >= isize))
return 0;
left = isize - *ppos;
if (unlikely(left < len))
len = left;
ret = 0;
spliced = 0;
while (len) {
ret = __generic_file_splice_read(in, ppos, pipe, len, flags);
@ -644,7 +654,6 @@ find_page:
* accessed, we are now done!
*/
mark_page_accessed(page);
balance_dirty_pages_ratelimited(mapping);
out:
page_cache_release(page);
unlock_page(page);
@ -815,6 +824,7 @@ generic_file_splice_write_nolock(struct pipe_inode_info *pipe, struct file *out,
if (err)
ret = err;
}
balance_dirty_pages_ratelimited(mapping);
}
return ret;
@ -868,6 +878,7 @@ generic_file_splice_write(struct pipe_inode_info *pipe, struct file *out,
if (err)
ret = err;
}
balance_dirty_pages_ratelimited(mapping);
}
return ret;
@ -922,7 +933,6 @@ static long do_splice_to(struct file *in, loff_t *ppos,
struct pipe_inode_info *pipe, size_t len,
unsigned int flags)
{
loff_t isize, left;
int ret;
if (unlikely(!in->f_op || !in->f_op->splice_read))
@ -935,14 +945,6 @@ static long do_splice_to(struct file *in, loff_t *ppos,
if (unlikely(ret < 0))
return ret;
isize = i_size_read(in->f_mapping->host);
if (unlikely(*ppos >= isize))
return 0;
left = isize - *ppos;
if (unlikely(left < len))
len = left;
return in->f_op->splice_read(in, ppos, pipe, len, flags);
}
@ -1058,8 +1060,6 @@ out_release:
return ret;
}
EXPORT_SYMBOL(do_splice_direct);
/*
* After the inode slimming patch, i_pipe/i_bdev/i_cdev share the same
* location, so checking ->i_pipe is not enough to verify that this is a

30
include/linux/pipe_fs_i.h
View File

@ -16,6 +16,21 @@ struct pipe_buffer {
unsigned int flags;
};
struct pipe_inode_info {
wait_queue_head_t wait;
unsigned int nrbufs, curbuf;
struct page *tmp_page;
unsigned int readers;
unsigned int writers;
unsigned int waiting_writers;
unsigned int r_counter;
unsigned int w_counter;
struct fasync_struct *fasync_readers;
struct fasync_struct *fasync_writers;
struct inode *inode;
struct pipe_buffer bufs[PIPE_BUFFERS];
};
/*
* Note on the nesting of these functions:
*
@ -38,21 +53,6 @@ struct pipe_buf_operations {
void (*get)(struct pipe_inode_info *, struct pipe_buffer *);
};
struct pipe_inode_info {
wait_queue_head_t wait;
unsigned int nrbufs, curbuf;
struct page *tmp_page;
unsigned int readers;
unsigned int writers;
unsigned int waiting_writers;
unsigned int r_counter;
unsigned int w_counter;
struct fasync_struct *fasync_readers;
struct fasync_struct *fasync_writers;
struct inode *inode;
struct pipe_buffer bufs[PIPE_BUFFERS];
};
/* Differs from PIPE_BUF in that PIPE_SIZE is the length of the actual
memory allocation, whereas PIPE_BUF makes atomicity guarantees. */
#define PIPE_SIZE PAGE_SIZE