Make netfslib pass the maximum length to the ->prepare_write() op to tell the cache how much it can expand the length of a write to. This allows a write to the server at the end of a file to be limited to a few bytes whilst writing an entire block to the cache (something required by direct I/O). Signed-off-by: David Howells <dhowells@xxxxxxxxxx> Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx> cc: linux-cachefs@xxxxxxxxxx cc: linux-fsdevel@xxxxxxxxxxxxxxx cc: linux-mm@xxxxxxxxx --- fs/cachefiles/internal.h | 2 +- fs/cachefiles/io.c | 10 ++++++---- fs/cachefiles/ondemand.c | 2 +- fs/netfs/fscache_io.c | 2 +- fs/netfs/io.c | 2 +- fs/netfs/objects.c | 1 + fs/netfs/output.c | 25 ++++++++++--------------- fs/smb/client/fscache.c | 2 +- include/linux/netfs.h | 5 +++-- 9 files changed, 25 insertions(+), 26 deletions(-) diff --git a/fs/cachefiles/internal.h b/fs/cachefiles/internal.h index 2ad58c465208..1af48d576a34 100644 --- a/fs/cachefiles/internal.h +++ b/fs/cachefiles/internal.h @@ -233,7 +233,7 @@ extern bool cachefiles_begin_operation(struct netfs_cache_resources *cres, enum fscache_want_state want_state); extern int __cachefiles_prepare_write(struct cachefiles_object *object, struct file *file, - loff_t *_start, size_t *_len, + loff_t *_start, size_t *_len, size_t upper_len, bool no_space_allocated_yet); extern int __cachefiles_write(struct cachefiles_object *object, struct file *file, diff --git a/fs/cachefiles/io.c b/fs/cachefiles/io.c index 009d23cd435b..bffffedce4a9 100644 --- a/fs/cachefiles/io.c +++ b/fs/cachefiles/io.c @@ -518,7 +518,7 @@ cachefiles_prepare_ondemand_read(struct netfs_cache_resources *cres, */ int __cachefiles_prepare_write(struct cachefiles_object *object, struct file *file, - loff_t *_start, size_t *_len, + loff_t *_start, size_t *_len, size_t upper_len, bool no_space_allocated_yet) { struct cachefiles_cache *cache = object->volume->cache; @@ -530,6 +530,8 @@ int __cachefiles_prepare_write(struct cachefiles_object *object, down = start - round_down(start, PAGE_SIZE); *_start = start - down; *_len = round_up(down + len, PAGE_SIZE); + if (down < start || *_len > upper_len) + return -ENOBUFS; /* We need to work out whether there's sufficient disk space to perform * the write - but we can skip that check if we have space already @@ -592,8 +594,8 @@ int __cachefiles_prepare_write(struct cachefiles_object *object, } static int cachefiles_prepare_write(struct netfs_cache_resources *cres, - loff_t *_start, size_t *_len, loff_t i_size, - bool no_space_allocated_yet) + loff_t *_start, size_t *_len, size_t upper_len, + loff_t i_size, bool no_space_allocated_yet) { struct cachefiles_object *object = cachefiles_cres_object(cres); struct cachefiles_cache *cache = object->volume->cache; @@ -609,7 +611,7 @@ static int cachefiles_prepare_write(struct netfs_cache_resources *cres, cachefiles_begin_secure(cache, &saved_cred); ret = __cachefiles_prepare_write(object, cachefiles_cres_file(cres), - _start, _len, + _start, _len, upper_len, no_space_allocated_yet); cachefiles_end_secure(cache, saved_cred); return ret; diff --git a/fs/cachefiles/ondemand.c b/fs/cachefiles/ondemand.c index 0254ed39f68c..9301d1eb0504 100644 --- a/fs/cachefiles/ondemand.c +++ b/fs/cachefiles/ondemand.c @@ -52,7 +52,7 @@ static ssize_t cachefiles_ondemand_fd_write_iter(struct kiocb *kiocb, return -ENOBUFS; cachefiles_begin_secure(cache, &saved_cred); - ret = __cachefiles_prepare_write(object, file, &pos, &len, true); + ret = __cachefiles_prepare_write(object, file, &pos, &len, len, true); cachefiles_end_secure(cache, saved_cred); if (ret < 0) return ret; diff --git a/fs/netfs/fscache_io.c b/fs/netfs/fscache_io.c index 79171a687930..ad572f7ee897 100644 --- a/fs/netfs/fscache_io.c +++ b/fs/netfs/fscache_io.c @@ -237,7 +237,7 @@ void __fscache_write_to_cache(struct fscache_cookie *cookie, fscache_access_io_write) < 0) goto abandon_free; - ret = cres->ops->prepare_write(cres, &start, &len, i_size, false); + ret = cres->ops->prepare_write(cres, &start, &len, len, i_size, false); if (ret < 0) goto abandon_end; diff --git a/fs/netfs/io.c b/fs/netfs/io.c index 01c7ff27228e..14c18be5aca0 100644 --- a/fs/netfs/io.c +++ b/fs/netfs/io.c @@ -199,7 +199,7 @@ static void netfs_rreq_do_write_to_cache(struct netfs_io_request *rreq) } ret = cres->ops->prepare_write(cres, &subreq->start, &subreq->len, - rreq->i_size, true); + subreq->len, rreq->i_size, true); if (ret < 0) { trace_netfs_failure(rreq, subreq, ret, netfs_fail_prepare_write); trace_netfs_sreq(subreq, netfs_sreq_trace_write_skip); diff --git a/fs/netfs/objects.c b/fs/netfs/objects.c index 93f1d7431199..b4e3bd836e5d 100644 --- a/fs/netfs/objects.c +++ b/fs/netfs/objects.c @@ -33,6 +33,7 @@ struct netfs_io_request *netfs_alloc_request(struct address_space *mapping, rreq->start = start; rreq->len = len; + rreq->upper_len = len; rreq->origin = origin; rreq->netfs_ops = ctx->ops; rreq->mapping = mapping; diff --git a/fs/netfs/output.c b/fs/netfs/output.c index 560cbcea0c0a..cc9065733b42 100644 --- a/fs/netfs/output.c +++ b/fs/netfs/output.c @@ -280,7 +280,7 @@ EXPORT_SYMBOL(netfs_queue_write_request); */ static void netfs_set_up_write_to_cache(struct netfs_io_request *wreq) { - struct netfs_cache_resources *cres; + struct netfs_cache_resources *cres = &wreq->cache_resources; struct netfs_io_subrequest *subreq; struct netfs_inode *ctx = netfs_inode(wreq->inode); struct fscache_cookie *cookie = netfs_i_cookie(ctx); @@ -294,26 +294,21 @@ static void netfs_set_up_write_to_cache(struct netfs_io_request *wreq) } _debug("write to cache"); - subreq = netfs_create_write_request(wreq, NETFS_WRITE_TO_CACHE, start, len, - netfs_write_to_cache_op_worker); - if (!subreq) + ret = fscache_begin_write_operation(cres, cookie); + if (ret < 0) return; - cres = &wreq->cache_resources; - ret = fscache_begin_read_operation(cres, cookie); - if (ret < 0) { - netfs_write_subrequest_terminated(subreq, ret, false); + ret = cres->ops->prepare_write(cres, &start, &len, wreq->upper_len, + i_size_read(wreq->inode), true); + if (ret < 0) return; - } - ret = cres->ops->prepare_write(cres, &start, &len, i_size_read(wreq->inode), - true); - if (ret < 0) { - netfs_write_subrequest_terminated(subreq, ret, false); + subreq = netfs_create_write_request(wreq, NETFS_WRITE_TO_CACHE, start, len, + netfs_write_to_cache_op_worker); + if (!subreq) return; - } - netfs_queue_write_request(subreq); + netfs_write_to_cache_op(subreq); } /* diff --git a/fs/smb/client/fscache.c b/fs/smb/client/fscache.c index e5cad149f5a2..c4a3cb736881 100644 --- a/fs/smb/client/fscache.c +++ b/fs/smb/client/fscache.c @@ -180,7 +180,7 @@ static int fscache_fallback_write_pages(struct inode *inode, loff_t start, size_ if (ret < 0) return ret; - ret = cres.ops->prepare_write(&cres, &start, &len, i_size_read(inode), + ret = cres.ops->prepare_write(&cres, &start, &len, len, i_size_read(inode), no_space_allocated_yet); if (ret == 0) ret = fscache_write(&cres, start, &iter, NULL, NULL); diff --git a/include/linux/netfs.h b/include/linux/netfs.h index a2e53ab06a1b..506c543f6888 100644 --- a/include/linux/netfs.h +++ b/include/linux/netfs.h @@ -262,6 +262,7 @@ struct netfs_io_request { atomic_t nr_copy_ops; /* Number of copy-to-cache ops in progress */ size_t submitted; /* Amount submitted for I/O so far */ size_t len; /* Length of the request */ + size_t upper_len; /* Length can be extended to here */ size_t transferred; /* Amount to be indicated as transferred */ short error; /* 0 or error that occurred */ enum netfs_io_origin origin; /* Origin of the request */ @@ -358,8 +359,8 @@ struct netfs_cache_ops { * actually do. */ int (*prepare_write)(struct netfs_cache_resources *cres, - loff_t *_start, size_t *_len, loff_t i_size, - bool no_space_allocated_yet); + loff_t *_start, size_t *_len, size_t upper_len, + loff_t i_size, bool no_space_allocated_yet); /* Prepare an on-demand read operation, shortening it to a cached/uncached * boundary as appropriate. -- You received this message because you are subscribed to the Google Groups "linux-cachefs@xxxxxxxxxx" group. 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