From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:57663) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1b2u75-0007LC-Tj for qemu-devel@nongnu.org; Wed, 18 May 2016 01:33:45 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1b2u73-0001bL-MQ for qemu-devel@nongnu.org; Wed, 18 May 2016 01:33:42 -0400 Received: from mx-v6.kamp.de ([2a02:248:0:51::16]:41099 helo=mx01.kamp.de) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1b2u73-0001bA-DI for qemu-devel@nongnu.org; Wed, 18 May 2016 01:33:41 -0400 From: Peter Lieven Date: Tue, 17 May 2016 16:11:54 +0200 Message-Id: <1463494315-12578-2-git-send-email-pl@kamp.de> In-Reply-To: <1463494315-12578-1-git-send-email-pl@kamp.de> References: <1463494315-12578-1-git-send-email-pl@kamp.de> Subject: [Qemu-devel] [PATCH 1/2] block/nfs: add support for libnfs pagecache List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-block@nongnu.org Cc: ronniesahlberg@gmail.com, jcody@redhat.com, qemu-devel@nongnu.org, Peter Lieven upcoming libnfs will have support for a read cache that can significantly help to speed up requests since libnfs by design circumvents the kernel cache. Example: qemu -cdrom nfs://127.0.0.1/iso/my.iso?pagecache=1024 The pagecache parameters takes the maximum amount of pages to cache. A page in libnfs is always the NFS_BLKSIZE which is 4KB. Signed-off-by: Peter Lieven --- block/nfs.c | 40 ++++++++++++++++++++++++++++++++++++---- 1 file changed, 36 insertions(+), 4 deletions(-) diff --git a/block/nfs.c b/block/nfs.c index 9f51cc3..975510f 100644 --- a/block/nfs.c +++ b/block/nfs.c @@ -1,7 +1,7 @@ /* * QEMU Block driver for native access to files on NFS shares * - * Copyright (c) 2014 Peter Lieven + * Copyright (c) 2014-2016 Peter Lieven * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal @@ -38,6 +38,7 @@ #include #define QEMU_NFS_MAX_READAHEAD_SIZE 1048576 +#define QEMU_NFS_MAX_PAGECACHE_SIZE (8388608 / NFS_BLKSIZE) #define QEMU_NFS_MAX_DEBUG_LEVEL 2 typedef struct NFSClient { @@ -278,7 +279,7 @@ static void nfs_file_close(BlockDriverState *bs) } static int64_t nfs_client_open(NFSClient *client, const char *filename, - int flags, Error **errp) + int flags, Error **errp, int open_flags) { int ret = -EINVAL, i; struct stat st; @@ -336,6 +337,9 @@ static int64_t nfs_client_open(NFSClient *client, const char *filename, val = QEMU_NFS_MAX_READAHEAD_SIZE; } nfs_set_readahead(client->context, val); +#ifdef LIBNFS_FEATURE_PAGECACHE + nfs_set_pagecache_ttl(client->context, 0); +#endif #endif #ifdef LIBNFS_FEATURE_DEBUG } else if (!strcmp(qp->p[i].name, "debug")) { @@ -348,6 +352,21 @@ static int64_t nfs_client_open(NFSClient *client, const char *filename, } nfs_set_debug(client->context, val); #endif +#ifdef LIBNFS_FEATURE_PAGECACHE + } else if (!strcmp(qp->p[i].name, "pagecache")) { + if (open_flags & BDRV_O_NOCACHE) { + error_setg(errp, "Cannot enable NFS pagecache " + "if cache.direct = on"); + goto fail; + } + if (val > QEMU_NFS_MAX_PAGECACHE_SIZE) { + error_report("NFS Warning: Truncating NFS pagecache" + " size to %d pages", QEMU_NFS_MAX_PAGECACHE_SIZE); + val = QEMU_NFS_MAX_PAGECACHE_SIZE; + } + nfs_set_pagecache(client->context, val); + nfs_set_pagecache_ttl(client->context, 0); +#endif } else { error_setg(errp, "Unknown NFS parameter name: %s", qp->p[i].name); @@ -418,7 +437,7 @@ static int nfs_file_open(BlockDriverState *bs, QDict *options, int flags, } ret = nfs_client_open(client, qemu_opt_get(opts, "filename"), (flags & BDRV_O_RDWR) ? O_RDWR : O_RDONLY, - errp); + errp, bs->open_flags); if (ret < 0) { goto out; } @@ -454,7 +473,7 @@ static int nfs_file_create(const char *url, QemuOpts *opts, Error **errp) total_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0), BDRV_SECTOR_SIZE); - ret = nfs_client_open(client, url, O_CREAT, errp); + ret = nfs_client_open(client, url, O_CREAT, errp, 0); if (ret < 0) { goto out; } @@ -530,6 +549,15 @@ static int nfs_reopen_prepare(BDRVReopenState *state, return 0; } +#ifdef LIBNFS_FEATURE_PAGECACHE +static void nfs_invalidate_cache(BlockDriverState *bs, + Error **errp) +{ + NFSClient *client = bs->opaque; + nfs_pagecache_invalidate(client->context, client->fh); +} +#endif + static BlockDriver bdrv_nfs = { .format_name = "nfs", .protocol_name = "nfs", @@ -553,6 +581,10 @@ static BlockDriver bdrv_nfs = { .bdrv_detach_aio_context = nfs_detach_aio_context, .bdrv_attach_aio_context = nfs_attach_aio_context, + +#ifdef LIBNFS_FEATURE_PAGECACHE + .bdrv_invalidate_cache = nfs_invalidate_cache, +#endif }; static void nfs_block_init(void) -- 1.9.1