diff options
Diffstat (limited to 'fs/cachefiles/cache.c')
| -rw-r--r-- | fs/cachefiles/cache.c | 17 |
1 files changed, 11 insertions, 6 deletions
diff --git a/fs/cachefiles/cache.c b/fs/cachefiles/cache.c index ce4d4785003c..7077f72e6f47 100644 --- a/fs/cachefiles/cache.c +++ b/fs/cachefiles/cache.c @@ -49,11 +49,19 @@ int cachefiles_add_cache(struct cachefiles_cache *cache) goto error_unsupported; } - /* check parameters */ + /* Check features of the backing filesystem: + * - Directories must support looking up and directory creation + * - We create tmpfiles to handle invalidation + * - We use xattrs to store metadata + * - We need to be able to query the amount of space available + * - We want to be able to sync the filesystem when stopping the cache + * - We use DIO to/from pages, so the blocksize mustn't be too big. + */ ret = -EOPNOTSUPP; if (d_is_negative(root) || !d_backing_inode(root)->i_op->lookup || !d_backing_inode(root)->i_op->mkdir || + !d_backing_inode(root)->i_op->tmpfile || !(d_backing_inode(root)->i_opflags & IOP_XATTR) || !root->d_sb->s_op->statfs || !root->d_sb->s_op->sync_fs || @@ -84,9 +92,7 @@ int cachefiles_add_cache(struct cachefiles_cache *cache) goto error_unsupported; cache->bsize = stats.f_bsize; - cache->bshift = 0; - if (stats.f_bsize < PAGE_SIZE) - cache->bshift = PAGE_SHIFT - ilog2(stats.f_bsize); + cache->bshift = ilog2(stats.f_bsize); _debug("blksize %u (shift %u)", cache->bsize, cache->bshift); @@ -106,7 +112,6 @@ int cachefiles_add_cache(struct cachefiles_cache *cache) (unsigned long long) cache->fcull, (unsigned long long) cache->fstop); - stats.f_blocks >>= cache->bshift; do_div(stats.f_blocks, 100); cache->bstop = stats.f_blocks * cache->bstop_percent; cache->bcull = stats.f_blocks * cache->bcull_percent; @@ -209,7 +214,7 @@ int cachefiles_has_space(struct cachefiles_cache *cache, return ret; } - b_avail = stats.f_bavail >> cache->bshift; + b_avail = stats.f_bavail; b_writing = atomic_long_read(&cache->b_writing); if (b_avail > b_writing) b_avail -= b_writing; |