---
name: "page_cache_sync_readahead"
section: "9"
platform: "linux"
package: "linux-manual-4.9"
version: "4.9.228-1"
release: "Debian 9 (Stretch)"
platforms: ["linux"]
url: "https://new.carta.tech/page_cache_sync_readahead"
---

# page\_cache\_sync\_readahead(9)

generic file readahead

## NAME

page\_cache\_sync\_readahead - generic file readahead

## SYNOPSIS

**void page\_cache\_sync\_readahead(struct address\_space \*** *mapping***, struct file\_ra\_state \*** *ra***, struct file \*** *filp***, pgoff\_t** *offset***, unsigned long** *req\_size***);**

## ARGUMENTS

*mapping*

address\_space which holds the pagecache and I/O vectors

*ra*

file\_ra\_state which holds the readahead state

*filp*

passed on to -\>**readpage** and -\>**readpages**

*offset*

start offset into *mapping*, in pagecache page-sized units

*req\_size*

hint: total size of the read which the caller is performing in pagecache pages

## DESCRIPTION

**page\_cache\_sync\_readahead** should be called when a cache miss happened: it will submit the read. The readahead logic may decide to piggyback more pages onto the read request if access patterns suggest it will improve performance.

## COPYRIGHT