diff options
| -rw-r--r-- | fs/cachefiles/internal.h | 9 | ||||
| -rw-r--r-- | fs/cachefiles/io.c | 15 | ||||
| -rw-r--r-- | fs/cachefiles/ondemand.c | 77 | ||||
| -rw-r--r-- | include/linux/netfs.h | 1 | ||||
| -rw-r--r-- | include/uapi/linux/cachefiles.h | 17 |
5 files changed, 117 insertions, 2 deletions
diff --git a/fs/cachefiles/internal.h b/fs/cachefiles/internal.h index da388ba127eb..6cba2c6de2f9 100644 --- a/fs/cachefiles/internal.h +++ b/fs/cachefiles/internal.h @@ -292,6 +292,9 @@ extern int cachefiles_ondemand_copen(struct cachefiles_cache *cache, extern int cachefiles_ondemand_init_object(struct cachefiles_object *object); extern void cachefiles_ondemand_clean_object(struct cachefiles_object *object); +extern int cachefiles_ondemand_read(struct cachefiles_object *object, + loff_t pos, size_t len); + #else static inline ssize_t cachefiles_ondemand_daemon_read(struct cachefiles_cache *cache, char __user *_buffer, size_t buflen) @@ -307,6 +310,12 @@ static inline int cachefiles_ondemand_init_object(struct cachefiles_object *obje static inline void cachefiles_ondemand_clean_object(struct cachefiles_object *object) { } + +static inline int cachefiles_ondemand_read(struct cachefiles_object *object, + loff_t pos, size_t len) +{ + return -EOPNOTSUPP; +} #endif /* diff --git a/fs/cachefiles/io.c b/fs/cachefiles/io.c index 50a14e8f0aac..000a28f46e59 100644 --- a/fs/cachefiles/io.c +++ b/fs/cachefiles/io.c @@ -403,6 +403,7 @@ static enum netfs_io_source cachefiles_prepare_read(struct netfs_io_subrequest * enum netfs_io_source ret = NETFS_DOWNLOAD_FROM_SERVER; loff_t off, to; ino_t ino = file ? file_inode(file)->i_ino : 0; + int rc; _enter("%zx @%llx/%llx", subreq->len, subreq->start, i_size); @@ -415,7 +416,8 @@ static enum netfs_io_source cachefiles_prepare_read(struct netfs_io_subrequest * if (test_bit(FSCACHE_COOKIE_NO_DATA_TO_READ, &cookie->flags)) { __set_bit(NETFS_SREQ_COPY_TO_CACHE, &subreq->flags); why = cachefiles_trace_read_no_data; - goto out_no_object; + if (!test_bit(NETFS_SREQ_ONDEMAND, &subreq->flags)) + goto out_no_object; } /* The object and the file may be being created in the background. */ @@ -432,7 +434,7 @@ static enum netfs_io_source cachefiles_prepare_read(struct netfs_io_subrequest * object = cachefiles_cres_object(cres); cache = object->volume->cache; cachefiles_begin_secure(cache, &saved_cred); - +retry: off = cachefiles_inject_read_error(); if (off == 0) off = vfs_llseek(file, subreq->start, SEEK_DATA); @@ -483,6 +485,15 @@ static enum netfs_io_source cachefiles_prepare_read(struct netfs_io_subrequest * download_and_store: __set_bit(NETFS_SREQ_COPY_TO_CACHE, &subreq->flags); + if (test_bit(NETFS_SREQ_ONDEMAND, &subreq->flags)) { + rc = cachefiles_ondemand_read(object, subreq->start, + subreq->len); + if (!rc) { + __clear_bit(NETFS_SREQ_ONDEMAND, &subreq->flags); + goto retry; + } + ret = NETFS_INVALID_READ; + } out: cachefiles_end_secure(cache, saved_cred); out_no_object: diff --git a/fs/cachefiles/ondemand.c b/fs/cachefiles/ondemand.c index 11b1c15ac697..3470d4e8f0cb 100644 --- a/fs/cachefiles/ondemand.c +++ b/fs/cachefiles/ondemand.c @@ -10,8 +10,25 @@ static int cachefiles_ondemand_fd_release(struct inode *inode, struct cachefiles_object *object = file->private_data; struct cachefiles_cache *cache = object->volume->cache; int object_id = object->ondemand_id; + struct cachefiles_req *req; + XA_STATE(xas, &cache->reqs, 0); + xa_lock(&cache->reqs); object->ondemand_id = CACHEFILES_ONDEMAND_ID_CLOSED; + + /* + * Flush all pending READ requests since their completion depends on + * anon_fd. + */ + xas_for_each(&xas, req, ULONG_MAX) { + if (req->msg.opcode == CACHEFILES_OP_READ) { + req->error = -EIO; + complete(&req->done); + xas_store(&xas, NULL); + } + } + xa_unlock(&cache->reqs); + xa_erase(&cache->ondemand_ids, object_id); cachefiles_put_object(object, cachefiles_obj_put_ondemand_fd); cachefiles_put_unbind_pincount(cache); @@ -57,11 +74,35 @@ static loff_t cachefiles_ondemand_fd_llseek(struct file *filp, loff_t pos, return vfs_llseek(file, pos, whence); } +static long cachefiles_ondemand_fd_ioctl(struct file *filp, unsigned int ioctl, + unsigned long arg) +{ + struct cachefiles_object *object = filp->private_data; + struct cachefiles_cache *cache = object->volume->cache; + struct cachefiles_req *req; + unsigned long id; + + if (ioctl != CACHEFILES_IOC_READ_COMPLETE) + return -EINVAL; + + if (!test_bit(CACHEFILES_ONDEMAND_MODE, &cache->flags)) + return -EOPNOTSUPP; + + id = arg; + req = xa_erase(&cache->reqs, id); + if (!req) + return -EINVAL; + + complete(&req->done); + return 0; +} + static const struct file_operations cachefiles_ondemand_fd_fops = { .owner = THIS_MODULE, .release = cachefiles_ondemand_fd_release, .write_iter = cachefiles_ondemand_fd_write_iter, .llseek = cachefiles_ondemand_fd_llseek, + .unlocked_ioctl = cachefiles_ondemand_fd_ioctl, }; /* @@ -388,6 +429,32 @@ static int cachefiles_ondemand_init_close_req(struct cachefiles_req *req, return 0; } +struct cachefiles_read_ctx { + loff_t off; + size_t len; +}; + +static int cachefiles_ondemand_init_read_req(struct cachefiles_req *req, + void *private) +{ + struct cachefiles_object *object = req->object; + struct cachefiles_read *load = (void *)req->msg.data; + struct cachefiles_read_ctx *read_ctx = private; + int object_id = object->ondemand_id; + + /* Stop enqueuing requests when daemon has closed anon_fd. */ + if (object_id <= 0) { + WARN_ON_ONCE(object_id == 0); + pr_info_once("READ: anonymous fd closed prematurely.\n"); + return -EIO; + } + + req->msg.object_id = object_id; + load->off = read_ctx->off; + load->len = read_ctx->len; + return 0; +} + int cachefiles_ondemand_init_object(struct cachefiles_object *object) { struct fscache_cookie *cookie = object->cookie; @@ -417,3 +484,13 @@ void cachefiles_ondemand_clean_object(struct cachefiles_object *object) cachefiles_ondemand_send_req(object, CACHEFILES_OP_CLOSE, 0, cachefiles_ondemand_init_close_req, NULL); } + +int cachefiles_ondemand_read(struct cachefiles_object *object, + loff_t pos, size_t len) +{ + struct cachefiles_read_ctx read_ctx = {pos, len}; + + return cachefiles_ondemand_send_req(object, CACHEFILES_OP_READ, + sizeof(struct cachefiles_read), + cachefiles_ondemand_init_read_req, &read_ctx); +} diff --git a/include/linux/netfs.h b/include/linux/netfs.h index c7bf1eaf51d5..057d04efaf79 100644 --- a/include/linux/netfs.h +++ b/include/linux/netfs.h @@ -159,6 +159,7 @@ struct netfs_io_subrequest { #define NETFS_SREQ_SHORT_IO 2 /* Set if the I/O was short */ #define NETFS_SREQ_SEEK_DATA_READ 3 /* Set if ->read() should SEEK_DATA first */ #define NETFS_SREQ_NO_PROGRESS 4 /* Set if we didn't manage to read any data */ +#define NETFS_SREQ_ONDEMAND 5 /* Set if it's from on-demand read mode */ }; enum netfs_io_origin { diff --git a/include/uapi/linux/cachefiles.h b/include/uapi/linux/cachefiles.h index 37a0071037c8..78caa73e5343 100644 --- a/include/uapi/linux/cachefiles.h +++ b/include/uapi/linux/cachefiles.h @@ -3,6 +3,7 @@ #define _LINUX_CACHEFILES_H #include <linux/types.h> +#include <linux/ioctl.h> /* * Fscache ensures that the maximum length of cookie key is 255. The volume key @@ -13,6 +14,7 @@ enum cachefiles_opcode { CACHEFILES_OP_OPEN, CACHEFILES_OP_CLOSE, + CACHEFILES_OP_READ, }; /* @@ -48,4 +50,19 @@ struct cachefiles_open { __u8 data[]; }; +/* + * @off indicates the starting offset of the requested file range + * @len indicates the length of the requested file range + */ +struct cachefiles_read { + __u64 off; + __u64 len; +}; + +/* + * Reply for READ request + * @arg for this ioctl is the @id field of READ request. + */ +#define CACHEFILES_IOC_READ_COMPLETE _IOW(0x98, 1, int) + #endif |