From: Jeffle Xu <jefflexu@linux.alibaba.com> To: dhowells@redhat.com, linux-cachefs@redhat.com, xiang@kernel.org, chao@kernel.org, linux-erofs@lists.ozlabs.org Cc: linux-fsdevel@vger.kernel.org, joseph.qi@linux.alibaba.com, bo.liu@linux.alibaba.com, tao.peng@linux.alibaba.com, gerry@linux.alibaba.com, eguan@linux.alibaba.com, linux-kernel@vger.kernel.org Subject: [PATCH v1 21/23] cachefiles: implement .read() for demand read Date: Mon, 27 Dec 2021 20:54:42 +0800 [thread overview] Message-ID: <20211227125444.21187-22-jefflexu@linux.alibaba.com> (raw) In-Reply-To: <20211227125444.21187-1-jefflexu@linux.alibaba.com> Once notified, user daemon need to get more details of the request by reading the devnode. The readed information includes the file range of the request, with which user daemon could somehow prepare corresponding data (e.g. download from remote through network) and fill the hole. Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com> --- fs/cachefiles/daemon.c | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) diff --git a/fs/cachefiles/daemon.c b/fs/cachefiles/daemon.c index 311dcd911a85..ce4cc5617dfc 100644 --- a/fs/cachefiles/daemon.c +++ b/fs/cachefiles/daemon.c @@ -29,6 +29,8 @@ static ssize_t cachefiles_daemon_write(struct file *, const char __user *, size_t, loff_t *); static __poll_t cachefiles_daemon_poll(struct file *, struct poll_table_struct *); +static ssize_t cachefiles_demand_read(struct file *, char __user *, size_t, + loff_t *); static __poll_t cachefiles_demand_poll(struct file *, struct poll_table_struct *); static int cachefiles_daemon_frun(struct cachefiles_cache *, char *); @@ -63,6 +65,7 @@ const struct file_operations cachefiles_demand_fops = { .owner = THIS_MODULE, .open = cachefiles_daemon_open, .release = cachefiles_daemon_release, + .read = cachefiles_demand_read, .write = cachefiles_daemon_write, .poll = cachefiles_demand_poll, .llseek = noop_llseek, @@ -322,6 +325,32 @@ static __poll_t cachefiles_daemon_poll(struct file *file, return mask; } +static ssize_t cachefiles_demand_read(struct file *file, char __user *_buffer, + size_t buflen, loff_t *pos) +{ + struct cachefiles_cache *cache = file->private_data; + struct cachefiles_req *req; + int n, id = 0; + + if (!test_bit(CACHEFILES_READY, &cache->flags)) + return 0; + + spin_lock(&cache->reqs_lock); + req = idr_get_next(&cache->reqs, &id); + spin_unlock(&cache->reqs_lock); + if (!req) + return 0; + + n = sizeof(req->req_in); + if (n > buflen) + return -EMSGSIZE; + + if (copy_to_user(_buffer, &req->req_in, n) != 0) + return -EFAULT; + + return n; +} + static __poll_t cachefiles_demand_poll(struct file *file, struct poll_table_struct *poll) { -- 2.27.0
WARNING: multiple messages have this Message-ID (diff)
From: Jeffle Xu <jefflexu@linux.alibaba.com> To: dhowells@redhat.com, linux-cachefs@redhat.com, xiang@kernel.org, chao@kernel.org, linux-erofs@lists.ozlabs.org Cc: tao.peng@linux.alibaba.com, linux-kernel@vger.kernel.org, joseph.qi@linux.alibaba.com, bo.liu@linux.alibaba.com, linux-fsdevel@vger.kernel.org, eguan@linux.alibaba.com, gerry@linux.alibaba.com Subject: [PATCH v1 21/23] cachefiles: implement .read() for demand read Date: Mon, 27 Dec 2021 20:54:42 +0800 [thread overview] Message-ID: <20211227125444.21187-22-jefflexu@linux.alibaba.com> (raw) In-Reply-To: <20211227125444.21187-1-jefflexu@linux.alibaba.com> Once notified, user daemon need to get more details of the request by reading the devnode. The readed information includes the file range of the request, with which user daemon could somehow prepare corresponding data (e.g. download from remote through network) and fill the hole. Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com> --- fs/cachefiles/daemon.c | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) diff --git a/fs/cachefiles/daemon.c b/fs/cachefiles/daemon.c index 311dcd911a85..ce4cc5617dfc 100644 --- a/fs/cachefiles/daemon.c +++ b/fs/cachefiles/daemon.c @@ -29,6 +29,8 @@ static ssize_t cachefiles_daemon_write(struct file *, const char __user *, size_t, loff_t *); static __poll_t cachefiles_daemon_poll(struct file *, struct poll_table_struct *); +static ssize_t cachefiles_demand_read(struct file *, char __user *, size_t, + loff_t *); static __poll_t cachefiles_demand_poll(struct file *, struct poll_table_struct *); static int cachefiles_daemon_frun(struct cachefiles_cache *, char *); @@ -63,6 +65,7 @@ const struct file_operations cachefiles_demand_fops = { .owner = THIS_MODULE, .open = cachefiles_daemon_open, .release = cachefiles_daemon_release, + .read = cachefiles_demand_read, .write = cachefiles_daemon_write, .poll = cachefiles_demand_poll, .llseek = noop_llseek, @@ -322,6 +325,32 @@ static __poll_t cachefiles_daemon_poll(struct file *file, return mask; } +static ssize_t cachefiles_demand_read(struct file *file, char __user *_buffer, + size_t buflen, loff_t *pos) +{ + struct cachefiles_cache *cache = file->private_data; + struct cachefiles_req *req; + int n, id = 0; + + if (!test_bit(CACHEFILES_READY, &cache->flags)) + return 0; + + spin_lock(&cache->reqs_lock); + req = idr_get_next(&cache->reqs, &id); + spin_unlock(&cache->reqs_lock); + if (!req) + return 0; + + n = sizeof(req->req_in); + if (n > buflen) + return -EMSGSIZE; + + if (copy_to_user(_buffer, &req->req_in, n) != 0) + return -EFAULT; + + return n; +} + static __poll_t cachefiles_demand_poll(struct file *file, struct poll_table_struct *poll) { -- 2.27.0
next prev parent reply other threads:[~2021-12-27 12:55 UTC|newest] Thread overview: 90+ messages / expand[flat|nested] mbox.gz Atom feed top 2021-12-27 12:54 [PATCH v1 00/23] fscache,erofs: fscache-based demand-read semantics Jeffle Xu 2021-12-27 12:54 ` Jeffle Xu 2021-12-27 12:54 ` [PATCH v1 01/23] cachefiles: add cachefiles_demand devnode Jeffle Xu 2021-12-27 12:54 ` Jeffle Xu 2021-12-28 2:47 ` Joseph Qi 2021-12-28 2:47 ` Joseph Qi 2021-12-28 12:34 ` JeffleXu 2021-12-28 12:34 ` JeffleXu 2021-12-27 12:54 ` [PATCH v1 02/23] cachefiles: add mode command to distinguish modes Jeffle Xu 2021-12-27 12:54 ` Jeffle Xu 2021-12-27 12:54 ` [PATCH v1 03/23] cachefiles: detect backing file size in demand-read mode Jeffle Xu 2021-12-27 12:54 ` Jeffle Xu 2021-12-27 12:54 ` [PATCH v1 04/23] netfs: make ops->init_rreq() optional Jeffle Xu 2021-12-27 12:54 ` Jeffle Xu 2021-12-27 12:54 ` [PATCH v1 05/23] netfs: add inode parameter to netfs_alloc_read_request() Jeffle Xu 2021-12-27 12:54 ` Jeffle Xu 2022-01-04 14:00 ` Gao Xiang 2022-01-04 14:00 ` Gao Xiang 2022-01-13 3:10 ` [Linux-cachefs] " JeffleXu 2022-01-13 3:10 ` JeffleXu 2022-01-13 12:09 ` Gao Xiang 2022-01-13 12:09 ` Gao Xiang 2021-12-27 12:54 ` [PATCH v1 06/23] erofs: export erofs_map_blocks() Jeffle Xu 2021-12-27 12:54 ` Jeffle Xu 2021-12-27 12:54 ` [PATCH v1 07/23] erofs: add nodev mode Jeffle Xu 2021-12-27 12:54 ` Jeffle Xu 2022-01-04 14:33 ` Gao Xiang 2022-01-04 14:33 ` Gao Xiang 2022-01-04 14:58 ` Gao Xiang 2022-01-04 14:58 ` Gao Xiang 2022-01-05 9:04 ` JeffleXu 2021-12-27 12:54 ` [PATCH v1 08/23] erofs: register global fscache volume Jeffle Xu 2021-12-27 12:54 ` Jeffle Xu 2021-12-27 12:54 ` [PATCH v1 09/23] erofs: add cookie context helper functions Jeffle Xu 2021-12-27 12:54 ` Jeffle Xu 2021-12-27 12:54 ` [PATCH v1 10/23] erofs: add anonymous inode managing page cache of blob file Jeffle Xu 2021-12-27 12:54 ` Jeffle Xu 2021-12-27 12:54 ` [PATCH v1 11/23] erofs: register cookie context for bootstrap Jeffle Xu 2021-12-27 12:54 ` Jeffle Xu 2021-12-27 12:54 ` [PATCH v1 12/23] erofs: implement fscache-based metadata read Jeffle Xu 2021-12-27 12:54 ` Jeffle Xu 2021-12-27 17:07 ` kernel test robot 2021-12-27 17:07 ` kernel test robot 2021-12-27 17:07 ` kernel test robot 2021-12-27 17:17 ` kernel test robot 2021-12-27 17:17 ` kernel test robot 2021-12-27 17:17 ` kernel test robot 2021-12-27 12:54 ` [PATCH v1 13/23] erofs: implement fscache-based data read Jeffle Xu 2021-12-27 12:54 ` Jeffle Xu 2022-01-03 6:32 ` JeffleXu 2022-01-03 6:32 ` JeffleXu 2022-01-04 14:40 ` Gao Xiang 2022-01-04 14:40 ` Gao Xiang 2022-01-05 2:29 ` JeffleXu 2021-12-27 12:54 ` [PATCH v1 14/23] erofs: register cookie context for data blobs Jeffle Xu 2021-12-27 12:54 ` Jeffle Xu 2021-12-27 12:54 ` [PATCH v1 15/23] erofs: implement fscache-based data read " Jeffle Xu 2021-12-27 12:54 ` Jeffle Xu 2021-12-27 12:54 ` [PATCH v1 16/23] erofs: add 'uuid' mount option Jeffle Xu 2021-12-27 12:54 ` Jeffle Xu 2021-12-27 12:54 ` [PATCH v1 17/23] netfs: support on demand read Jeffle Xu 2021-12-27 12:54 ` Jeffle Xu 2021-12-27 12:54 ` [PATCH v1 18/23] cachefiles: use idr tree managing pending " Jeffle Xu 2021-12-27 12:54 ` Jeffle Xu 2021-12-27 12:54 ` [PATCH v1 19/23] cachefiles: implement .demand_read() for " Jeffle Xu 2021-12-27 12:54 ` Jeffle Xu 2021-12-27 15:32 ` kernel test robot 2021-12-27 15:32 ` kernel test robot 2021-12-27 15:32 ` kernel test robot 2021-12-27 15:36 ` Matthew Wilcox 2021-12-27 15:36 ` Matthew Wilcox 2021-12-28 12:33 ` JeffleXu 2021-12-28 12:33 ` JeffleXu 2022-01-12 9:02 ` JeffleXu 2022-01-12 9:02 ` JeffleXu 2022-01-19 13:20 ` Matthew Wilcox 2022-01-19 13:20 ` Matthew Wilcox 2022-01-20 12:43 ` JeffleXu 2022-01-20 12:43 ` JeffleXu 2021-12-27 15:55 ` kernel test robot 2021-12-27 15:55 ` kernel test robot 2021-12-27 15:55 ` kernel test robot 2021-12-27 12:54 ` [PATCH v1 20/23] cachefiles: implement .poll() " Jeffle Xu 2021-12-27 12:54 ` Jeffle Xu 2021-12-27 12:54 ` Jeffle Xu [this message] 2021-12-27 12:54 ` [PATCH v1 21/23] cachefiles: implement .read() " Jeffle Xu 2021-12-27 12:54 ` [PATCH v1 22/23] cachefiles: add done command " Jeffle Xu 2021-12-27 12:54 ` Jeffle Xu 2021-12-27 12:54 ` [PATCH v1 23/23] erofs: support on " Jeffle Xu 2021-12-27 12:54 ` Jeffle Xu
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