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Diffstat (limited to 'mm/filemap.c')
-rw-r--r--mm/filemap.c249
1 files changed, 25 insertions, 224 deletions
diff --git a/mm/filemap.c b/mm/filemap.c
index 26b992d169e..0876cc57255 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -1302,8 +1302,8 @@ static int fastcall page_cache_read(struct file * file, unsigned long offset)
/**
* filemap_fault - read in file data for page fault handling
- * @vma: user vma (not used)
- * @fdata: the applicable fault_data
+ * @vma: vma in which the fault was taken
+ * @vmf: struct vm_fault containing details of the fault
*
* filemap_fault() is invoked via the vma operations vector for a
* mapped memory region to read in file data during a page fault.
@@ -1312,7 +1312,7 @@ static int fastcall page_cache_read(struct file * file, unsigned long offset)
* it in the page cache, and handles the special cases reasonably without
* having a lot of duplicated code.
*/
-struct page *filemap_fault(struct vm_area_struct *vma, struct fault_data *fdata)
+int filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
{
int error;
struct file *file = vma->vm_file;
@@ -1322,13 +1322,12 @@ struct page *filemap_fault(struct vm_area_struct *vma, struct fault_data *fdata)
struct page *page;
unsigned long size;
int did_readaround = 0;
+ int ret;
- fdata->type = VM_FAULT_MINOR;
-
- BUG_ON(!(vma->vm_flags & VM_CAN_INVALIDATE));
+ ret = VM_FAULT_MINOR;
size = (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
- if (fdata->pgoff >= size)
+ if (vmf->pgoff >= size)
goto outside_data_content;
/* If we don't want any read-ahead, don't bother */
@@ -1342,18 +1341,18 @@ struct page *filemap_fault(struct vm_area_struct *vma, struct fault_data *fdata)
* For sequential accesses, we use the generic readahead logic.
*/
if (VM_SequentialReadHint(vma))
- page_cache_readahead(mapping, ra, file, fdata->pgoff, 1);
+ page_cache_readahead(mapping, ra, file, vmf->pgoff, 1);
/*
* Do we have something in the page cache already?
*/
retry_find:
- page = find_lock_page(mapping, fdata->pgoff);
+ page = find_lock_page(mapping, vmf->pgoff);
if (!page) {
unsigned long ra_pages;
if (VM_SequentialReadHint(vma)) {
- handle_ra_miss(mapping, ra, fdata->pgoff);
+ handle_ra_miss(mapping, ra, vmf->pgoff);
goto no_cached_page;
}
ra->mmap_miss++;
@@ -1370,7 +1369,7 @@ retry_find:
* check did_readaround, as this is an inner loop.
*/
if (!did_readaround) {
- fdata->type = VM_FAULT_MAJOR;
+ ret = VM_FAULT_MAJOR;
count_vm_event(PGMAJFAULT);
}
did_readaround = 1;
@@ -1378,11 +1377,11 @@ retry_find:
if (ra_pages) {
pgoff_t start = 0;
- if (fdata->pgoff > ra_pages / 2)
- start = fdata->pgoff - ra_pages / 2;
+ if (vmf->pgoff > ra_pages / 2)
+ start = vmf->pgoff - ra_pages / 2;
do_page_cache_readahead(mapping, file, start, ra_pages);
}
- page = find_lock_page(mapping, fdata->pgoff);
+ page = find_lock_page(mapping, vmf->pgoff);
if (!page)
goto no_cached_page;
}
@@ -1399,7 +1398,7 @@ retry_find:
/* Must recheck i_size under page lock */
size = (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
- if (unlikely(fdata->pgoff >= size)) {
+ if (unlikely(vmf->pgoff >= size)) {
unlock_page(page);
goto outside_data_content;
}
@@ -1408,24 +1407,24 @@ retry_find:
* Found the page and have a reference on it.
*/
mark_page_accessed(page);
- return page;
+ vmf->page = page;
+ return ret | FAULT_RET_LOCKED;
outside_data_content:
/*
* An external ptracer can access pages that normally aren't
* accessible..
*/
- if (vma->vm_mm == current->mm) {
- fdata->type = VM_FAULT_SIGBUS;
- return NULL;
- }
+ if (vma->vm_mm == current->mm)
+ return VM_FAULT_SIGBUS;
+
/* Fall through to the non-read-ahead case */
no_cached_page:
/*
* We're only likely to ever get here if MADV_RANDOM is in
* effect.
*/
- error = page_cache_read(file, fdata->pgoff);
+ error = page_cache_read(file, vmf->pgoff);
/*
* The page we want has now been added to the page cache.
@@ -1441,15 +1440,13 @@ no_cached_page:
* to schedule I/O.
*/
if (error == -ENOMEM)
- fdata->type = VM_FAULT_OOM;
- else
- fdata->type = VM_FAULT_SIGBUS;
- return NULL;
+ return VM_FAULT_OOM;
+ return VM_FAULT_SIGBUS;
page_not_uptodate:
/* IO error path */
if (!did_readaround) {
- fdata->type = VM_FAULT_MAJOR;
+ ret = VM_FAULT_MAJOR;
count_vm_event(PGMAJFAULT);
}
@@ -1468,206 +1465,10 @@ page_not_uptodate:
/* Things didn't work out. Return zero to tell the mm layer so. */
shrink_readahead_size_eio(file, ra);
- fdata->type = VM_FAULT_SIGBUS;
- return NULL;
+ return VM_FAULT_SIGBUS;
}
EXPORT_SYMBOL(filemap_fault);
-/*
- * filemap_nopage and filemap_populate are legacy exports that are not used
- * in tree. Scheduled for removal.
- */
-struct page *filemap_nopage(struct vm_area_struct *area,
- unsigned long address, int *type)
-{
- struct page *page;
- struct fault_data fdata;
- fdata.address = address;
- fdata.pgoff = ((address - area->vm_start) >> PAGE_CACHE_SHIFT)
- + area->vm_pgoff;
- fdata.flags = 0;
-
- page = filemap_fault(area, &fdata);
- if (type)
- *type = fdata.type;
-
- return page;
-}
-EXPORT_SYMBOL(filemap_nopage);
-
-static struct page * filemap_getpage(struct file *file, unsigned long pgoff,
- int nonblock)
-{
- struct address_space *mapping = file->f_mapping;
- struct page *page;
- int error;
-
- /*
- * Do we have something in the page cache already?
- */
-retry_find:
- page = find_get_page(mapping, pgoff);
- if (!page) {
- if (nonblock)
- return NULL;
- goto no_cached_page;
- }
-
- /*
- * Ok, found a page in the page cache, now we need to check
- * that it's up-to-date.
- */
- if (!PageUptodate(page)) {
- if (nonblock) {
- page_cache_release(page);
- return NULL;
- }
- goto page_not_uptodate;
- }
-
-success:
- /*
- * Found the page and have a reference on it.
- */
- mark_page_accessed(page);
- return page;
-
-no_cached_page:
- error = page_cache_read(file, pgoff);
-
- /*
- * The page we want has now been added to the page cache.
- * In the unlikely event that someone removed it in the
- * meantime, we'll just come back here and read it again.
- */
- if (error >= 0)
- goto retry_find;
-
- /*
- * An error return from page_cache_read can result if the
- * system is low on memory, or a problem occurs while trying
- * to schedule I/O.
- */
- return NULL;
-
-page_not_uptodate:
- lock_page(page);
-
- /* Did it get truncated while we waited for it? */
- if (!page->mapping) {
- unlock_page(page);
- goto err;
- }
-
- /* Did somebody else get it up-to-date? */
- if (PageUptodate(page)) {
- unlock_page(page);
- goto success;
- }
-
- error = mapping->a_ops->readpage(file, page);
- if (!error) {
- wait_on_page_locked(page);
- if (PageUptodate(page))
- goto success;
- } else if (error == AOP_TRUNCATED_PAGE) {
- page_cache_release(page);
- goto retry_find;
- }
-
- /*
- * Umm, take care of errors if the page isn't up-to-date.
- * Try to re-read it _once_. We do this synchronously,
- * because there really aren't any performance issues here
- * and we need to check for errors.
- */
- lock_page(page);
-
- /* Somebody truncated the page on us? */
- if (!page->mapping) {
- unlock_page(page);
- goto err;
- }
- /* Somebody else successfully read it in? */
- if (PageUptodate(page)) {
- unlock_page(page);
- goto success;
- }
-
- ClearPageError(page);
- error = mapping->a_ops->readpage(file, page);
- if (!error) {
- wait_on_page_locked(page);
- if (PageUptodate(page))
- goto success;
- } else if (error == AOP_TRUNCATED_PAGE) {
- page_cache_release(page);
- goto retry_find;
- }
-
- /*
- * Things didn't work out. Return zero to tell the
- * mm layer so, possibly freeing the page cache page first.
- */
-err:
- page_cache_release(page);
-
- return NULL;
-}
-
-int filemap_populate(struct vm_area_struct *vma, unsigned long addr,
- unsigned long len, pgprot_t prot, unsigned long pgoff,
- int nonblock)
-{
- struct file *file = vma->vm_file;
- struct address_space *mapping = file->f_mapping;
- struct inode *inode = mapping->host;
- unsigned long size;
- struct mm_struct *mm = vma->vm_mm;
- struct page *page;
- int err;
-
- if (!nonblock)
- force_page_cache_readahead(mapping, vma->vm_file,
- pgoff, len >> PAGE_CACHE_SHIFT);
-
-repeat:
- size = (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
- if (pgoff + (len >> PAGE_CACHE_SHIFT) > size)
- return -EINVAL;
-
- page = filemap_getpage(file, pgoff, nonblock);
-
- /* XXX: This is wrong, a filesystem I/O error may have happened. Fix that as
- * done in shmem_populate calling shmem_getpage */
- if (!page && !nonblock)
- return -ENOMEM;
-
- if (page) {
- err = install_page(mm, vma, addr, page, prot);
- if (err) {
- page_cache_release(page);
- return err;
- }
- } else if (vma->vm_flags & VM_NONLINEAR) {
- /* No page was found just because we can't read it in now (being
- * here implies nonblock != 0), but the page may exist, so set
- * the PTE to fault it in later. */
- err = install_file_pte(mm, vma, addr, pgoff, prot);
- if (err)
- return err;
- }
-
- len -= PAGE_SIZE;
- addr += PAGE_SIZE;
- pgoff++;
- if (len)
- goto repeat;
-
- return 0;
-}
-EXPORT_SYMBOL(filemap_populate);
-
struct vm_operations_struct generic_file_vm_ops = {
.fault = filemap_fault,
};
@@ -1682,7 +1483,7 @@ int generic_file_mmap(struct file * file, struct vm_area_struct * vma)
return -ENOEXEC;
file_accessed(file);
vma->vm_ops = &generic_file_vm_ops;
- vma->vm_flags |= VM_CAN_INVALIDATE | VM_CAN_NONLINEAR;
+ vma->vm_flags |= VM_CAN_NONLINEAR;
return 0;
}