ext4: remove unneeded check for error allocating bio_post_read_ctx

Since allocating an object from a mempool never fails when
__GFP_DIRECT_RECLAIM (which is included in GFP_NOFS) is set, the check
for failure to allocate a bio_post_read_ctx is unnecessary.  Remove it.

Also remove the redundant assignment to ->bi_private.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20191231181256.47770-1-ebiggers@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This commit is contained in:
Eric Biggers 2019-12-31 12:12:56 -06:00 committed by Theodore Ts'o
parent 68e45330e3
commit fd5fe25356
1 changed files with 8 additions and 17 deletions

View File

@ -189,12 +189,11 @@ static inline bool ext4_need_verity(const struct inode *inode, pgoff_t idx)
idx < DIV_ROUND_UP(inode->i_size, PAGE_SIZE); idx < DIV_ROUND_UP(inode->i_size, PAGE_SIZE);
} }
static struct bio_post_read_ctx *get_bio_post_read_ctx(struct inode *inode, static void ext4_set_bio_post_read_ctx(struct bio *bio,
struct bio *bio, const struct inode *inode,
pgoff_t first_idx) pgoff_t first_idx)
{ {
unsigned int post_read_steps = 0; unsigned int post_read_steps = 0;
struct bio_post_read_ctx *ctx = NULL;
if (IS_ENCRYPTED(inode) && S_ISREG(inode->i_mode)) if (IS_ENCRYPTED(inode) && S_ISREG(inode->i_mode))
post_read_steps |= 1 << STEP_DECRYPT; post_read_steps |= 1 << STEP_DECRYPT;
@ -203,14 +202,14 @@ static struct bio_post_read_ctx *get_bio_post_read_ctx(struct inode *inode,
post_read_steps |= 1 << STEP_VERITY; post_read_steps |= 1 << STEP_VERITY;
if (post_read_steps) { if (post_read_steps) {
ctx = mempool_alloc(bio_post_read_ctx_pool, GFP_NOFS); /* Due to the mempool, this never fails. */
if (!ctx) struct bio_post_read_ctx *ctx =
return ERR_PTR(-ENOMEM); mempool_alloc(bio_post_read_ctx_pool, GFP_NOFS);
ctx->bio = bio; ctx->bio = bio;
ctx->enabled_steps = post_read_steps; ctx->enabled_steps = post_read_steps;
bio->bi_private = ctx; bio->bi_private = ctx;
} }
return ctx;
} }
static inline loff_t ext4_readpage_limit(struct inode *inode) static inline loff_t ext4_readpage_limit(struct inode *inode)
@ -371,24 +370,16 @@ int ext4_mpage_readpages(struct address_space *mapping,
bio = NULL; bio = NULL;
} }
if (bio == NULL) { if (bio == NULL) {
struct bio_post_read_ctx *ctx;
/* /*
* bio_alloc will _always_ be able to allocate a bio if * bio_alloc will _always_ be able to allocate a bio if
* __GFP_DIRECT_RECLAIM is set, see bio_alloc_bioset(). * __GFP_DIRECT_RECLAIM is set, see bio_alloc_bioset().
*/ */
bio = bio_alloc(GFP_KERNEL, bio = bio_alloc(GFP_KERNEL,
min_t(int, nr_pages, BIO_MAX_PAGES)); min_t(int, nr_pages, BIO_MAX_PAGES));
ctx = get_bio_post_read_ctx(inode, bio, page->index); ext4_set_bio_post_read_ctx(bio, inode, page->index);
if (IS_ERR(ctx)) {
bio_put(bio);
bio = NULL;
goto set_error_page;
}
bio_set_dev(bio, bdev); bio_set_dev(bio, bdev);
bio->bi_iter.bi_sector = blocks[0] << (blkbits - 9); bio->bi_iter.bi_sector = blocks[0] << (blkbits - 9);
bio->bi_end_io = mpage_end_io; bio->bi_end_io = mpage_end_io;
bio->bi_private = ctx;
bio_set_op_attrs(bio, REQ_OP_READ, bio_set_op_attrs(bio, REQ_OP_READ,
is_readahead ? REQ_RAHEAD : 0); is_readahead ? REQ_RAHEAD : 0);
} }