diff options
Diffstat (limited to 'fs/overlayfs/file.c')
| -rw-r--r-- | fs/overlayfs/file.c | 162 |
1 files changed, 148 insertions, 14 deletions
diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c index e235a635d9ec..a5317216de73 100644 --- a/fs/overlayfs/file.c +++ b/fs/overlayfs/file.c @@ -9,8 +9,19 @@ #include <linux/xattr.h> #include <linux/uio.h> #include <linux/uaccess.h> +#include <linux/splice.h> +#include <linux/mm.h> +#include <linux/fs.h> #include "overlayfs.h" +struct ovl_aio_req { + struct kiocb iocb; + struct kiocb *orig_iocb; + struct fd fd; +}; + +static struct kmem_cache *ovl_aio_request_cachep; + static char ovl_whatisit(struct inode *inode, struct inode *realinode) { if (realinode != ovl_inode_upper(inode)) @@ -146,7 +157,7 @@ static loff_t ovl_llseek(struct file *file, loff_t offset, int whence) struct inode *inode = file_inode(file); struct fd real; const struct cred *old_cred; - ssize_t ret; + loff_t ret; /* * The two special cases below do not need to involve real fs, @@ -171,7 +182,7 @@ static loff_t ovl_llseek(struct file *file, loff_t offset, int whence) * limitations that are more strict than ->s_maxbytes for specific * files, so we use the real file to perform seeks. */ - inode_lock(inode); + ovl_inode_lock(inode); real.file->f_pos = file->f_pos; old_cred = ovl_override_creds(inode->i_sb); @@ -179,7 +190,7 @@ static loff_t ovl_llseek(struct file *file, loff_t offset, int whence) revert_creds(old_cred); file->f_pos = real.file->f_pos; - inode_unlock(inode); + ovl_inode_unlock(inode); fdput(real); @@ -225,6 +236,33 @@ static rwf_t ovl_iocb_to_rwf(struct kiocb *iocb) return flags; } +static void ovl_aio_cleanup_handler(struct ovl_aio_req *aio_req) +{ + struct kiocb *iocb = &aio_req->iocb; + struct kiocb *orig_iocb = aio_req->orig_iocb; + + if (iocb->ki_flags & IOCB_WRITE) { + struct inode *inode = file_inode(orig_iocb->ki_filp); + + file_end_write(iocb->ki_filp); + ovl_copyattr(ovl_inode_real(inode), inode); + } + + orig_iocb->ki_pos = iocb->ki_pos; + fdput(aio_req->fd); + kmem_cache_free(ovl_aio_request_cachep, aio_req); +} + +static void ovl_aio_rw_complete(struct kiocb *iocb, long res, long res2) +{ + struct ovl_aio_req *aio_req = container_of(iocb, + struct ovl_aio_req, iocb); + struct kiocb *orig_iocb = aio_req->orig_iocb; + + ovl_aio_cleanup_handler(aio_req); + orig_iocb->ki_complete(orig_iocb, res, res2); +} + static ssize_t ovl_read_iter(struct kiocb *iocb, struct iov_iter *iter) { struct file *file = iocb->ki_filp; @@ -240,10 +278,28 @@ static ssize_t ovl_read_iter(struct kiocb *iocb, struct iov_iter *iter) return ret; old_cred = ovl_override_creds(file_inode(file)->i_sb); - ret = vfs_iter_read(real.file, iter, &iocb->ki_pos, - ovl_iocb_to_rwf(iocb)); + if (is_sync_kiocb(iocb)) { + ret = vfs_iter_read(real.file, iter, &iocb->ki_pos, + ovl_iocb_to_rwf(iocb)); + } else { + struct ovl_aio_req *aio_req; + + ret = -ENOMEM; + aio_req = kmem_cache_zalloc(ovl_aio_request_cachep, GFP_KERNEL); + if (!aio_req) + goto out; + + aio_req->fd = real; + real.flags = 0; + aio_req->orig_iocb = iocb; + kiocb_clone(&aio_req->iocb, iocb, real.file); + aio_req->iocb.ki_complete = ovl_aio_rw_complete; + ret = vfs_iocb_iter_read(real.file, &aio_req->iocb, iter); + if (ret != -EIOCBQUEUED) + ovl_aio_cleanup_handler(aio_req); + } +out: revert_creds(old_cred); - ovl_file_accessed(file); fdput(real); @@ -274,15 +330,33 @@ static ssize_t ovl_write_iter(struct kiocb *iocb, struct iov_iter *iter) goto out_unlock; old_cred = ovl_override_creds(file_inode(file)->i_sb); - file_start_write(real.file); - ret = vfs_iter_write(real.file, iter, &iocb->ki_pos, - ovl_iocb_to_rwf(iocb)); - file_end_write(real.file); + if (is_sync_kiocb(iocb)) { + file_start_write(real.file); + ret = vfs_iter_write(real.file, iter, &iocb->ki_pos, + ovl_iocb_to_rwf(iocb)); + file_end_write(real.file); + /* Update size */ + ovl_copyattr(ovl_inode_real(inode), inode); + } else { + struct ovl_aio_req *aio_req; + + ret = -ENOMEM; + aio_req = kmem_cache_zalloc(ovl_aio_request_cachep, GFP_KERNEL); + if (!aio_req) + goto out; + + file_start_write(real.file); + aio_req->fd = real; + real.flags = 0; + aio_req->orig_iocb = iocb; + kiocb_clone(&aio_req->iocb, iocb, real.file); + aio_req->iocb.ki_complete = ovl_aio_rw_complete; + ret = vfs_iocb_iter_write(real.file, &aio_req->iocb, iter); + if (ret != -EIOCBQUEUED) + ovl_aio_cleanup_handler(aio_req); + } +out: revert_creds(old_cred); - - /* Update size */ - ovl_copyattr(ovl_inode_real(inode), inode); - fdput(real); out_unlock: @@ -291,6 +365,48 @@ out_unlock: return ret; } +static ssize_t ovl_splice_read(struct file *in, loff_t *ppos, + struct pipe_inode_info *pipe, size_t len, + unsigned int flags) +{ + ssize_t ret; + struct fd real; + const struct cred *old_cred; + + ret = ovl_real_fdget(in, &real); + if (ret) + return ret; + + old_cred = ovl_override_creds(file_inode(in)->i_sb); + ret = generic_file_splice_read(real.file, ppos, pipe, len, flags); + revert_creds(old_cred); + + ovl_file_accessed(in); + fdput(real); + return ret; +} + +static ssize_t +ovl_splice_write(struct pipe_inode_info *pipe, struct file *out, + loff_t *ppos, size_t len, unsigned int flags) +{ + struct fd real; + const struct cred *old_cred; + ssize_t ret; + + ret = ovl_real_fdget(out, &real); + if (ret) + return ret; + + old_cred = ovl_override_creds(file_inode(out)->i_sb); + ret = iter_file_splice_write(pipe, real.file, ppos, len, flags); + revert_creds(old_cred); + + ovl_file_accessed(out); + fdput(real); + return ret; +} + static int ovl_fsync(struct file *file, loff_t start, loff_t end, int datasync) { struct fd real; @@ -647,7 +763,25 @@ const struct file_operations ovl_file_operations = { .fadvise = ovl_fadvise, .unlocked_ioctl = ovl_ioctl, .compat_ioctl = ovl_compat_ioctl, + .splice_read = ovl_splice_read, + .splice_write = ovl_splice_write, .copy_file_range = ovl_copy_file_range, .remap_file_range = ovl_remap_file_range, }; + +int __init ovl_aio_request_cache_init(void) +{ + ovl_aio_request_cachep = kmem_cache_create("ovl_aio_req", + sizeof(struct ovl_aio_req), + 0, SLAB_HWCACHE_ALIGN, NULL); + if (!ovl_aio_request_cachep) + return -ENOMEM; + + return 0; +} + +void ovl_aio_request_cache_destroy(void) +{ + kmem_cache_destroy(ovl_aio_request_cachep); +} |