diff options
| -rw-r--r-- | fs/nfsd/debugfs.c | 93 | ||||
| -rw-r--r-- | fs/nfsd/nfsd.h | 9 | ||||
| -rw-r--r-- | fs/nfsd/vfs.c | 21 |
3 files changed, 123 insertions, 0 deletions
diff --git a/fs/nfsd/debugfs.c b/fs/nfsd/debugfs.c index f07d790d56aa..ed2b9e066206 100644 --- a/fs/nfsd/debugfs.c +++ b/fs/nfsd/debugfs.c @@ -27,11 +27,98 @@ static int nfsd_dsr_get(void *data, u64 *val) static int nfsd_dsr_set(void *data, u64 val) { nfsd_disable_splice_read = (val > 0); + if (!nfsd_disable_splice_read) { + /* + * Must use buffered I/O if splice_read is enabled. + */ + nfsd_io_cache_read = NFSD_IO_BUFFERED; + } return 0; } DEFINE_DEBUGFS_ATTRIBUTE(nfsd_dsr_fops, nfsd_dsr_get, nfsd_dsr_set, "%llu\n"); +/* + * /sys/kernel/debug/nfsd/io_cache_read + * + * Contents: + * %0: NFS READ will use buffered IO + * %1: NFS READ will use dontcache (buffered IO w/ dropbehind) + * + * This setting takes immediate effect for all NFS versions, + * all exports, and in all NFSD net namespaces. + */ + +static int nfsd_io_cache_read_get(void *data, u64 *val) +{ + *val = nfsd_io_cache_read; + return 0; +} + +static int nfsd_io_cache_read_set(void *data, u64 val) +{ + int ret = 0; + + switch (val) { + case NFSD_IO_BUFFERED: + nfsd_io_cache_read = NFSD_IO_BUFFERED; + break; + case NFSD_IO_DONTCACHE: + /* + * Must disable splice_read when enabling + * NFSD_IO_DONTCACHE. + */ + nfsd_disable_splice_read = true; + nfsd_io_cache_read = val; + break; + default: + ret = -EINVAL; + break; + } + + return ret; +} + +DEFINE_DEBUGFS_ATTRIBUTE(nfsd_io_cache_read_fops, nfsd_io_cache_read_get, + nfsd_io_cache_read_set, "%llu\n"); + +/* + * /sys/kernel/debug/nfsd/io_cache_write + * + * Contents: + * %0: NFS WRITE will use buffered IO + * %1: NFS WRITE will use dontcache (buffered IO w/ dropbehind) + * + * This setting takes immediate effect for all NFS versions, + * all exports, and in all NFSD net namespaces. + */ + +static int nfsd_io_cache_write_get(void *data, u64 *val) +{ + *val = nfsd_io_cache_write; + return 0; +} + +static int nfsd_io_cache_write_set(void *data, u64 val) +{ + int ret = 0; + + switch (val) { + case NFSD_IO_BUFFERED: + case NFSD_IO_DONTCACHE: + nfsd_io_cache_write = val; + break; + default: + ret = -EINVAL; + break; + } + + return ret; +} + +DEFINE_DEBUGFS_ATTRIBUTE(nfsd_io_cache_write_fops, nfsd_io_cache_write_get, + nfsd_io_cache_write_set, "%llu\n"); + void nfsd_debugfs_exit(void) { debugfs_remove_recursive(nfsd_top_dir); @@ -44,4 +131,10 @@ void nfsd_debugfs_init(void) debugfs_create_file("disable-splice-read", S_IWUSR | S_IRUGO, nfsd_top_dir, NULL, &nfsd_dsr_fops); + + debugfs_create_file("io_cache_read", 0644, nfsd_top_dir, NULL, + &nfsd_io_cache_read_fops); + + debugfs_create_file("io_cache_write", 0644, nfsd_top_dir, NULL, + &nfsd_io_cache_write_fops); } diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h index 1cd0bed57bc2..809729d41e08 100644 --- a/fs/nfsd/nfsd.h +++ b/fs/nfsd/nfsd.h @@ -153,6 +153,15 @@ static inline void nfsd_debugfs_exit(void) {} extern bool nfsd_disable_splice_read __read_mostly; +enum { + /* Any new NFSD_IO enum value must be added at the end */ + NFSD_IO_BUFFERED, + NFSD_IO_DONTCACHE, +}; + +extern u64 nfsd_io_cache_read __read_mostly; +extern u64 nfsd_io_cache_write __read_mostly; + extern int nfsd_max_blksize; static inline int nfsd_v4client(struct svc_rqst *rq) diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index 3cd3b9e069f4..714777c221ed 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -49,6 +49,8 @@ #define NFSDDBG_FACILITY NFSDDBG_FILEOP bool nfsd_disable_splice_read __read_mostly; +u64 nfsd_io_cache_read __read_mostly = NFSD_IO_BUFFERED; +u64 nfsd_io_cache_write __read_mostly = NFSD_IO_BUFFERED; /** * nfserrno - Map Linux errnos to NFS errnos @@ -1099,6 +1101,16 @@ __be32 nfsd_iter_read(struct svc_rqst *rqstp, struct svc_fh *fhp, size_t len; init_sync_kiocb(&kiocb, file); + + switch (nfsd_io_cache_read) { + case NFSD_IO_BUFFERED: + break; + case NFSD_IO_DONTCACHE: + if (file->f_op->fop_flags & FOP_DONTCACHE) + kiocb.ki_flags = IOCB_DONTCACHE; + break; + } + kiocb.ki_pos = offset; v = 0; @@ -1224,6 +1236,15 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, since = READ_ONCE(file->f_wb_err); if (verf) nfsd_copy_write_verifier(verf, nn); + + switch (nfsd_io_cache_write) { + case NFSD_IO_BUFFERED: + break; + case NFSD_IO_DONTCACHE: + if (file->f_op->fop_flags & FOP_DONTCACHE) + kiocb.ki_flags |= IOCB_DONTCACHE; + break; + } host_err = vfs_iocb_iter_write(file, &kiocb, &iter); if (host_err < 0) { commit_reset_write_verifier(nn, rqstp, host_err); |