diff options
Diffstat (limited to 'fs/exofs/super.c')
| -rw-r--r-- | fs/exofs/super.c | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/fs/exofs/super.c b/fs/exofs/super.c index 78f5ad633d3b..e87510f4749e 100644 --- a/fs/exofs/super.c +++ b/fs/exofs/super.c @@ -390,6 +390,23 @@ static int _read_and_match_data_map(struct exofs_sb_info *sbi, unsigned numdevs, return 0; } +static unsigned __ra_pages(struct exofs_layout *layout) +{ + const unsigned _MIN_RA = 32; /* min 128K read-ahead */ + unsigned ra_pages = layout->group_width * layout->stripe_unit / + PAGE_SIZE; + unsigned max_io_pages = exofs_max_io_pages(layout, ~0); + + ra_pages *= 2; /* two stripes */ + if (ra_pages < _MIN_RA) + ra_pages = roundup(_MIN_RA, ra_pages / 2); + + if (ra_pages > max_io_pages) + ra_pages = max_io_pages; + + return ra_pages; +} + /* @odi is valid only as long as @fscb_dev is valid */ static int exofs_devs_2_odi(struct exofs_dt_device_info *dt_dev, struct osd_dev_info *odi) @@ -623,6 +640,7 @@ static int exofs_fill_super(struct super_block *sb, void *data, int silent) } /* set up operation vectors */ + sbi->bdi.ra_pages = __ra_pages(&sbi->layout); sb->s_bdi = &sbi->bdi; sb->s_fs_info = sbi; sb->s_op = &exofs_sops; |