forked from Minki/linux
f32d7ac20a
Since fscrypt users can now indicated if fscrypt_encrypt_page() should use a bounce page, we can delay the bounce page pool initialization util it is really needed. That is until fscrypt_operations has no FS_CFLG_OWN_PAGES flag set. Signed-off-by: David Gstir <david@sigma-star.at> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
617 lines
16 KiB
C
617 lines
16 KiB
C
/*
|
|
* This contains encryption functions for per-file encryption.
|
|
*
|
|
* Copyright (C) 2015, Google, Inc.
|
|
* Copyright (C) 2015, Motorola Mobility
|
|
*
|
|
* Written by Michael Halcrow, 2014.
|
|
*
|
|
* Filename encryption additions
|
|
* Uday Savagaonkar, 2014
|
|
* Encryption policy handling additions
|
|
* Ildar Muslukhov, 2014
|
|
* Add fscrypt_pullback_bio_page()
|
|
* Jaegeuk Kim, 2015.
|
|
*
|
|
* This has not yet undergone a rigorous security audit.
|
|
*
|
|
* The usage of AES-XTS should conform to recommendations in NIST
|
|
* Special Publication 800-38E and IEEE P1619/D16.
|
|
*/
|
|
|
|
#include <linux/pagemap.h>
|
|
#include <linux/mempool.h>
|
|
#include <linux/module.h>
|
|
#include <linux/scatterlist.h>
|
|
#include <linux/ratelimit.h>
|
|
#include <linux/bio.h>
|
|
#include <linux/dcache.h>
|
|
#include <linux/namei.h>
|
|
#include "fscrypt_private.h"
|
|
|
|
static unsigned int num_prealloc_crypto_pages = 32;
|
|
static unsigned int num_prealloc_crypto_ctxs = 128;
|
|
|
|
module_param(num_prealloc_crypto_pages, uint, 0444);
|
|
MODULE_PARM_DESC(num_prealloc_crypto_pages,
|
|
"Number of crypto pages to preallocate");
|
|
module_param(num_prealloc_crypto_ctxs, uint, 0444);
|
|
MODULE_PARM_DESC(num_prealloc_crypto_ctxs,
|
|
"Number of crypto contexts to preallocate");
|
|
|
|
static mempool_t *fscrypt_bounce_page_pool = NULL;
|
|
|
|
static LIST_HEAD(fscrypt_free_ctxs);
|
|
static DEFINE_SPINLOCK(fscrypt_ctx_lock);
|
|
|
|
static struct workqueue_struct *fscrypt_read_workqueue;
|
|
static DEFINE_MUTEX(fscrypt_init_mutex);
|
|
|
|
static struct kmem_cache *fscrypt_ctx_cachep;
|
|
struct kmem_cache *fscrypt_info_cachep;
|
|
|
|
/**
|
|
* fscrypt_release_ctx() - Releases an encryption context
|
|
* @ctx: The encryption context to release.
|
|
*
|
|
* If the encryption context was allocated from the pre-allocated pool, returns
|
|
* it to that pool. Else, frees it.
|
|
*
|
|
* If there's a bounce page in the context, this frees that.
|
|
*/
|
|
void fscrypt_release_ctx(struct fscrypt_ctx *ctx)
|
|
{
|
|
unsigned long flags;
|
|
|
|
if (ctx->flags & FS_WRITE_PATH_FL && ctx->w.bounce_page) {
|
|
mempool_free(ctx->w.bounce_page, fscrypt_bounce_page_pool);
|
|
ctx->w.bounce_page = NULL;
|
|
}
|
|
ctx->w.control_page = NULL;
|
|
if (ctx->flags & FS_CTX_REQUIRES_FREE_ENCRYPT_FL) {
|
|
kmem_cache_free(fscrypt_ctx_cachep, ctx);
|
|
} else {
|
|
spin_lock_irqsave(&fscrypt_ctx_lock, flags);
|
|
list_add(&ctx->free_list, &fscrypt_free_ctxs);
|
|
spin_unlock_irqrestore(&fscrypt_ctx_lock, flags);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(fscrypt_release_ctx);
|
|
|
|
/**
|
|
* fscrypt_get_ctx() - Gets an encryption context
|
|
* @inode: The inode for which we are doing the crypto
|
|
* @gfp_flags: The gfp flag for memory allocation
|
|
*
|
|
* Allocates and initializes an encryption context.
|
|
*
|
|
* Return: An allocated and initialized encryption context on success; error
|
|
* value or NULL otherwise.
|
|
*/
|
|
struct fscrypt_ctx *fscrypt_get_ctx(const struct inode *inode, gfp_t gfp_flags)
|
|
{
|
|
struct fscrypt_ctx *ctx = NULL;
|
|
struct fscrypt_info *ci = inode->i_crypt_info;
|
|
unsigned long flags;
|
|
|
|
if (ci == NULL)
|
|
return ERR_PTR(-ENOKEY);
|
|
|
|
/*
|
|
* We first try getting the ctx from a free list because in
|
|
* the common case the ctx will have an allocated and
|
|
* initialized crypto tfm, so it's probably a worthwhile
|
|
* optimization. For the bounce page, we first try getting it
|
|
* from the kernel allocator because that's just about as fast
|
|
* as getting it from a list and because a cache of free pages
|
|
* should generally be a "last resort" option for a filesystem
|
|
* to be able to do its job.
|
|
*/
|
|
spin_lock_irqsave(&fscrypt_ctx_lock, flags);
|
|
ctx = list_first_entry_or_null(&fscrypt_free_ctxs,
|
|
struct fscrypt_ctx, free_list);
|
|
if (ctx)
|
|
list_del(&ctx->free_list);
|
|
spin_unlock_irqrestore(&fscrypt_ctx_lock, flags);
|
|
if (!ctx) {
|
|
ctx = kmem_cache_zalloc(fscrypt_ctx_cachep, gfp_flags);
|
|
if (!ctx)
|
|
return ERR_PTR(-ENOMEM);
|
|
ctx->flags |= FS_CTX_REQUIRES_FREE_ENCRYPT_FL;
|
|
} else {
|
|
ctx->flags &= ~FS_CTX_REQUIRES_FREE_ENCRYPT_FL;
|
|
}
|
|
ctx->flags &= ~FS_WRITE_PATH_FL;
|
|
return ctx;
|
|
}
|
|
EXPORT_SYMBOL(fscrypt_get_ctx);
|
|
|
|
/**
|
|
* page_crypt_complete() - completion callback for page crypto
|
|
* @req: The asynchronous cipher request context
|
|
* @res: The result of the cipher operation
|
|
*/
|
|
static void page_crypt_complete(struct crypto_async_request *req, int res)
|
|
{
|
|
struct fscrypt_completion_result *ecr = req->data;
|
|
|
|
if (res == -EINPROGRESS)
|
|
return;
|
|
ecr->res = res;
|
|
complete(&ecr->completion);
|
|
}
|
|
|
|
typedef enum {
|
|
FS_DECRYPT = 0,
|
|
FS_ENCRYPT,
|
|
} fscrypt_direction_t;
|
|
|
|
static int do_page_crypto(const struct inode *inode,
|
|
fscrypt_direction_t rw, u64 lblk_num,
|
|
struct page *src_page, struct page *dest_page,
|
|
unsigned int len, unsigned int offs,
|
|
gfp_t gfp_flags)
|
|
{
|
|
struct {
|
|
__le64 index;
|
|
u8 padding[FS_XTS_TWEAK_SIZE - sizeof(__le64)];
|
|
} xts_tweak;
|
|
struct skcipher_request *req = NULL;
|
|
DECLARE_FS_COMPLETION_RESULT(ecr);
|
|
struct scatterlist dst, src;
|
|
struct fscrypt_info *ci = inode->i_crypt_info;
|
|
struct crypto_skcipher *tfm = ci->ci_ctfm;
|
|
int res = 0;
|
|
|
|
BUG_ON(len == 0);
|
|
|
|
req = skcipher_request_alloc(tfm, gfp_flags);
|
|
if (!req) {
|
|
printk_ratelimited(KERN_ERR
|
|
"%s: crypto_request_alloc() failed\n",
|
|
__func__);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
skcipher_request_set_callback(
|
|
req, CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
|
|
page_crypt_complete, &ecr);
|
|
|
|
BUILD_BUG_ON(sizeof(xts_tweak) != FS_XTS_TWEAK_SIZE);
|
|
xts_tweak.index = cpu_to_le64(lblk_num);
|
|
memset(xts_tweak.padding, 0, sizeof(xts_tweak.padding));
|
|
|
|
sg_init_table(&dst, 1);
|
|
sg_set_page(&dst, dest_page, len, offs);
|
|
sg_init_table(&src, 1);
|
|
sg_set_page(&src, src_page, len, offs);
|
|
skcipher_request_set_crypt(req, &src, &dst, len, &xts_tweak);
|
|
if (rw == FS_DECRYPT)
|
|
res = crypto_skcipher_decrypt(req);
|
|
else
|
|
res = crypto_skcipher_encrypt(req);
|
|
if (res == -EINPROGRESS || res == -EBUSY) {
|
|
BUG_ON(req->base.data != &ecr);
|
|
wait_for_completion(&ecr.completion);
|
|
res = ecr.res;
|
|
}
|
|
skcipher_request_free(req);
|
|
if (res) {
|
|
printk_ratelimited(KERN_ERR
|
|
"%s: crypto_skcipher_encrypt() returned %d\n",
|
|
__func__, res);
|
|
return res;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static struct page *alloc_bounce_page(struct fscrypt_ctx *ctx, gfp_t gfp_flags)
|
|
{
|
|
ctx->w.bounce_page = mempool_alloc(fscrypt_bounce_page_pool, gfp_flags);
|
|
if (ctx->w.bounce_page == NULL)
|
|
return ERR_PTR(-ENOMEM);
|
|
ctx->flags |= FS_WRITE_PATH_FL;
|
|
return ctx->w.bounce_page;
|
|
}
|
|
|
|
/**
|
|
* fscypt_encrypt_page() - Encrypts a page
|
|
* @inode: The inode for which the encryption should take place
|
|
* @page: The page to encrypt. Must be locked for bounce-page
|
|
* encryption.
|
|
* @len: Length of data to encrypt in @page and encrypted
|
|
* data in returned page.
|
|
* @offs: Offset of data within @page and returned
|
|
* page holding encrypted data.
|
|
* @lblk_num: Logical block number. This must be unique for multiple
|
|
* calls with same inode, except when overwriting
|
|
* previously written data.
|
|
* @gfp_flags: The gfp flag for memory allocation
|
|
*
|
|
* Encrypts @page using the ctx encryption context. Performs encryption
|
|
* either in-place or into a newly allocated bounce page.
|
|
* Called on the page write path.
|
|
*
|
|
* Bounce page allocation is the default.
|
|
* In this case, the contents of @page are encrypted and stored in an
|
|
* allocated bounce page. @page has to be locked and the caller must call
|
|
* fscrypt_restore_control_page() on the returned ciphertext page to
|
|
* release the bounce buffer and the encryption context.
|
|
*
|
|
* In-place encryption is used by setting the FS_CFLG_OWN_PAGES flag in
|
|
* fscrypt_operations. Here, the input-page is returned with its content
|
|
* encrypted.
|
|
*
|
|
* Return: A page with the encrypted content on success. Else, an
|
|
* error value or NULL.
|
|
*/
|
|
struct page *fscrypt_encrypt_page(const struct inode *inode,
|
|
struct page *page,
|
|
unsigned int len,
|
|
unsigned int offs,
|
|
u64 lblk_num, gfp_t gfp_flags)
|
|
|
|
{
|
|
struct fscrypt_ctx *ctx;
|
|
struct page *ciphertext_page = page;
|
|
int err;
|
|
|
|
BUG_ON(len % FS_CRYPTO_BLOCK_SIZE != 0);
|
|
|
|
if (inode->i_sb->s_cop->flags & FS_CFLG_OWN_PAGES) {
|
|
/* with inplace-encryption we just encrypt the page */
|
|
err = do_page_crypto(inode, FS_ENCRYPT, lblk_num,
|
|
page, ciphertext_page,
|
|
len, offs, gfp_flags);
|
|
if (err)
|
|
return ERR_PTR(err);
|
|
|
|
return ciphertext_page;
|
|
}
|
|
|
|
BUG_ON(!PageLocked(page));
|
|
|
|
ctx = fscrypt_get_ctx(inode, gfp_flags);
|
|
if (IS_ERR(ctx))
|
|
return (struct page *)ctx;
|
|
|
|
/* The encryption operation will require a bounce page. */
|
|
ciphertext_page = alloc_bounce_page(ctx, gfp_flags);
|
|
if (IS_ERR(ciphertext_page))
|
|
goto errout;
|
|
|
|
ctx->w.control_page = page;
|
|
err = do_page_crypto(inode, FS_ENCRYPT, lblk_num,
|
|
page, ciphertext_page,
|
|
len, offs, gfp_flags);
|
|
if (err) {
|
|
ciphertext_page = ERR_PTR(err);
|
|
goto errout;
|
|
}
|
|
SetPagePrivate(ciphertext_page);
|
|
set_page_private(ciphertext_page, (unsigned long)ctx);
|
|
lock_page(ciphertext_page);
|
|
return ciphertext_page;
|
|
|
|
errout:
|
|
fscrypt_release_ctx(ctx);
|
|
return ciphertext_page;
|
|
}
|
|
EXPORT_SYMBOL(fscrypt_encrypt_page);
|
|
|
|
/**
|
|
* fscrypt_decrypt_page() - Decrypts a page in-place
|
|
* @inode: The corresponding inode for the page to decrypt.
|
|
* @page: The page to decrypt. Must be locked in case
|
|
* it is a writeback page (FS_CFLG_OWN_PAGES unset).
|
|
* @len: Number of bytes in @page to be decrypted.
|
|
* @offs: Start of data in @page.
|
|
* @lblk_num: Logical block number.
|
|
*
|
|
* Decrypts page in-place using the ctx encryption context.
|
|
*
|
|
* Called from the read completion callback.
|
|
*
|
|
* Return: Zero on success, non-zero otherwise.
|
|
*/
|
|
int fscrypt_decrypt_page(const struct inode *inode, struct page *page,
|
|
unsigned int len, unsigned int offs, u64 lblk_num)
|
|
{
|
|
if (!(inode->i_sb->s_cop->flags & FS_CFLG_OWN_PAGES))
|
|
BUG_ON(!PageLocked(page));
|
|
|
|
return do_page_crypto(inode, FS_DECRYPT, lblk_num, page, page, len,
|
|
offs, GFP_NOFS);
|
|
}
|
|
EXPORT_SYMBOL(fscrypt_decrypt_page);
|
|
|
|
int fscrypt_zeroout_range(const struct inode *inode, pgoff_t lblk,
|
|
sector_t pblk, unsigned int len)
|
|
{
|
|
struct fscrypt_ctx *ctx;
|
|
struct page *ciphertext_page = NULL;
|
|
struct bio *bio;
|
|
int ret, err = 0;
|
|
|
|
BUG_ON(inode->i_sb->s_blocksize != PAGE_SIZE);
|
|
|
|
ctx = fscrypt_get_ctx(inode, GFP_NOFS);
|
|
if (IS_ERR(ctx))
|
|
return PTR_ERR(ctx);
|
|
|
|
ciphertext_page = alloc_bounce_page(ctx, GFP_NOWAIT);
|
|
if (IS_ERR(ciphertext_page)) {
|
|
err = PTR_ERR(ciphertext_page);
|
|
goto errout;
|
|
}
|
|
|
|
while (len--) {
|
|
err = do_page_crypto(inode, FS_ENCRYPT, lblk,
|
|
ZERO_PAGE(0), ciphertext_page,
|
|
PAGE_SIZE, 0, GFP_NOFS);
|
|
if (err)
|
|
goto errout;
|
|
|
|
bio = bio_alloc(GFP_NOWAIT, 1);
|
|
if (!bio) {
|
|
err = -ENOMEM;
|
|
goto errout;
|
|
}
|
|
bio->bi_bdev = inode->i_sb->s_bdev;
|
|
bio->bi_iter.bi_sector =
|
|
pblk << (inode->i_sb->s_blocksize_bits - 9);
|
|
bio_set_op_attrs(bio, REQ_OP_WRITE, 0);
|
|
ret = bio_add_page(bio, ciphertext_page,
|
|
inode->i_sb->s_blocksize, 0);
|
|
if (ret != inode->i_sb->s_blocksize) {
|
|
/* should never happen! */
|
|
WARN_ON(1);
|
|
bio_put(bio);
|
|
err = -EIO;
|
|
goto errout;
|
|
}
|
|
err = submit_bio_wait(bio);
|
|
if ((err == 0) && bio->bi_error)
|
|
err = -EIO;
|
|
bio_put(bio);
|
|
if (err)
|
|
goto errout;
|
|
lblk++;
|
|
pblk++;
|
|
}
|
|
err = 0;
|
|
errout:
|
|
fscrypt_release_ctx(ctx);
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL(fscrypt_zeroout_range);
|
|
|
|
/*
|
|
* Validate dentries for encrypted directories to make sure we aren't
|
|
* potentially caching stale data after a key has been added or
|
|
* removed.
|
|
*/
|
|
static int fscrypt_d_revalidate(struct dentry *dentry, unsigned int flags)
|
|
{
|
|
struct dentry *dir;
|
|
struct fscrypt_info *ci;
|
|
int dir_has_key, cached_with_key;
|
|
|
|
if (flags & LOOKUP_RCU)
|
|
return -ECHILD;
|
|
|
|
dir = dget_parent(dentry);
|
|
if (!d_inode(dir)->i_sb->s_cop->is_encrypted(d_inode(dir))) {
|
|
dput(dir);
|
|
return 0;
|
|
}
|
|
|
|
ci = d_inode(dir)->i_crypt_info;
|
|
if (ci && ci->ci_keyring_key &&
|
|
(ci->ci_keyring_key->flags & ((1 << KEY_FLAG_INVALIDATED) |
|
|
(1 << KEY_FLAG_REVOKED) |
|
|
(1 << KEY_FLAG_DEAD))))
|
|
ci = NULL;
|
|
|
|
/* this should eventually be an flag in d_flags */
|
|
spin_lock(&dentry->d_lock);
|
|
cached_with_key = dentry->d_flags & DCACHE_ENCRYPTED_WITH_KEY;
|
|
spin_unlock(&dentry->d_lock);
|
|
dir_has_key = (ci != NULL);
|
|
dput(dir);
|
|
|
|
/*
|
|
* If the dentry was cached without the key, and it is a
|
|
* negative dentry, it might be a valid name. We can't check
|
|
* if the key has since been made available due to locking
|
|
* reasons, so we fail the validation so ext4_lookup() can do
|
|
* this check.
|
|
*
|
|
* We also fail the validation if the dentry was created with
|
|
* the key present, but we no longer have the key, or vice versa.
|
|
*/
|
|
if ((!cached_with_key && d_is_negative(dentry)) ||
|
|
(!cached_with_key && dir_has_key) ||
|
|
(cached_with_key && !dir_has_key))
|
|
return 0;
|
|
return 1;
|
|
}
|
|
|
|
const struct dentry_operations fscrypt_d_ops = {
|
|
.d_revalidate = fscrypt_d_revalidate,
|
|
};
|
|
EXPORT_SYMBOL(fscrypt_d_ops);
|
|
|
|
/*
|
|
* Call fscrypt_decrypt_page on every single page, reusing the encryption
|
|
* context.
|
|
*/
|
|
static void completion_pages(struct work_struct *work)
|
|
{
|
|
struct fscrypt_ctx *ctx =
|
|
container_of(work, struct fscrypt_ctx, r.work);
|
|
struct bio *bio = ctx->r.bio;
|
|
struct bio_vec *bv;
|
|
int i;
|
|
|
|
bio_for_each_segment_all(bv, bio, i) {
|
|
struct page *page = bv->bv_page;
|
|
int ret = fscrypt_decrypt_page(page->mapping->host, page,
|
|
PAGE_SIZE, 0, page->index);
|
|
|
|
if (ret) {
|
|
WARN_ON_ONCE(1);
|
|
SetPageError(page);
|
|
} else {
|
|
SetPageUptodate(page);
|
|
}
|
|
unlock_page(page);
|
|
}
|
|
fscrypt_release_ctx(ctx);
|
|
bio_put(bio);
|
|
}
|
|
|
|
void fscrypt_decrypt_bio_pages(struct fscrypt_ctx *ctx, struct bio *bio)
|
|
{
|
|
INIT_WORK(&ctx->r.work, completion_pages);
|
|
ctx->r.bio = bio;
|
|
queue_work(fscrypt_read_workqueue, &ctx->r.work);
|
|
}
|
|
EXPORT_SYMBOL(fscrypt_decrypt_bio_pages);
|
|
|
|
void fscrypt_pullback_bio_page(struct page **page, bool restore)
|
|
{
|
|
struct fscrypt_ctx *ctx;
|
|
struct page *bounce_page;
|
|
|
|
/* The bounce data pages are unmapped. */
|
|
if ((*page)->mapping)
|
|
return;
|
|
|
|
/* The bounce data page is unmapped. */
|
|
bounce_page = *page;
|
|
ctx = (struct fscrypt_ctx *)page_private(bounce_page);
|
|
|
|
/* restore control page */
|
|
*page = ctx->w.control_page;
|
|
|
|
if (restore)
|
|
fscrypt_restore_control_page(bounce_page);
|
|
}
|
|
EXPORT_SYMBOL(fscrypt_pullback_bio_page);
|
|
|
|
void fscrypt_restore_control_page(struct page *page)
|
|
{
|
|
struct fscrypt_ctx *ctx;
|
|
|
|
ctx = (struct fscrypt_ctx *)page_private(page);
|
|
set_page_private(page, (unsigned long)NULL);
|
|
ClearPagePrivate(page);
|
|
unlock_page(page);
|
|
fscrypt_release_ctx(ctx);
|
|
}
|
|
EXPORT_SYMBOL(fscrypt_restore_control_page);
|
|
|
|
static void fscrypt_destroy(void)
|
|
{
|
|
struct fscrypt_ctx *pos, *n;
|
|
|
|
list_for_each_entry_safe(pos, n, &fscrypt_free_ctxs, free_list)
|
|
kmem_cache_free(fscrypt_ctx_cachep, pos);
|
|
INIT_LIST_HEAD(&fscrypt_free_ctxs);
|
|
mempool_destroy(fscrypt_bounce_page_pool);
|
|
fscrypt_bounce_page_pool = NULL;
|
|
}
|
|
|
|
/**
|
|
* fscrypt_initialize() - allocate major buffers for fs encryption.
|
|
* @cop_flags: fscrypt operations flags
|
|
*
|
|
* We only call this when we start accessing encrypted files, since it
|
|
* results in memory getting allocated that wouldn't otherwise be used.
|
|
*
|
|
* Return: Zero on success, non-zero otherwise.
|
|
*/
|
|
int fscrypt_initialize(unsigned int cop_flags)
|
|
{
|
|
int i, res = -ENOMEM;
|
|
|
|
/*
|
|
* No need to allocate a bounce page pool if there already is one or
|
|
* this FS won't use it.
|
|
*/
|
|
if (cop_flags & FS_CFLG_OWN_PAGES || fscrypt_bounce_page_pool)
|
|
return 0;
|
|
|
|
mutex_lock(&fscrypt_init_mutex);
|
|
if (fscrypt_bounce_page_pool)
|
|
goto already_initialized;
|
|
|
|
for (i = 0; i < num_prealloc_crypto_ctxs; i++) {
|
|
struct fscrypt_ctx *ctx;
|
|
|
|
ctx = kmem_cache_zalloc(fscrypt_ctx_cachep, GFP_NOFS);
|
|
if (!ctx)
|
|
goto fail;
|
|
list_add(&ctx->free_list, &fscrypt_free_ctxs);
|
|
}
|
|
|
|
fscrypt_bounce_page_pool =
|
|
mempool_create_page_pool(num_prealloc_crypto_pages, 0);
|
|
if (!fscrypt_bounce_page_pool)
|
|
goto fail;
|
|
|
|
already_initialized:
|
|
mutex_unlock(&fscrypt_init_mutex);
|
|
return 0;
|
|
fail:
|
|
fscrypt_destroy();
|
|
mutex_unlock(&fscrypt_init_mutex);
|
|
return res;
|
|
}
|
|
|
|
/**
|
|
* fscrypt_init() - Set up for fs encryption.
|
|
*/
|
|
static int __init fscrypt_init(void)
|
|
{
|
|
fscrypt_read_workqueue = alloc_workqueue("fscrypt_read_queue",
|
|
WQ_HIGHPRI, 0);
|
|
if (!fscrypt_read_workqueue)
|
|
goto fail;
|
|
|
|
fscrypt_ctx_cachep = KMEM_CACHE(fscrypt_ctx, SLAB_RECLAIM_ACCOUNT);
|
|
if (!fscrypt_ctx_cachep)
|
|
goto fail_free_queue;
|
|
|
|
fscrypt_info_cachep = KMEM_CACHE(fscrypt_info, SLAB_RECLAIM_ACCOUNT);
|
|
if (!fscrypt_info_cachep)
|
|
goto fail_free_ctx;
|
|
|
|
return 0;
|
|
|
|
fail_free_ctx:
|
|
kmem_cache_destroy(fscrypt_ctx_cachep);
|
|
fail_free_queue:
|
|
destroy_workqueue(fscrypt_read_workqueue);
|
|
fail:
|
|
return -ENOMEM;
|
|
}
|
|
module_init(fscrypt_init)
|
|
|
|
/**
|
|
* fscrypt_exit() - Shutdown the fs encryption system
|
|
*/
|
|
static void __exit fscrypt_exit(void)
|
|
{
|
|
fscrypt_destroy();
|
|
|
|
if (fscrypt_read_workqueue)
|
|
destroy_workqueue(fscrypt_read_workqueue);
|
|
kmem_cache_destroy(fscrypt_ctx_cachep);
|
|
kmem_cache_destroy(fscrypt_info_cachep);
|
|
}
|
|
module_exit(fscrypt_exit);
|
|
|
|
MODULE_LICENSE("GPL");
|