From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:49946) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XpGaM-0007r6-4K for qemu-devel@nongnu.org; Fri, 14 Nov 2014 08:06:52 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XpGaF-0003Jw-QY for qemu-devel@nongnu.org; Fri, 14 Nov 2014 08:06:46 -0500 Received: from mx1.redhat.com ([209.132.183.28]:52707) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XpGaF-0003Ji-K8 for qemu-devel@nongnu.org; Fri, 14 Nov 2014 08:06:39 -0500 From: Max Reitz Date: Fri, 14 Nov 2014 14:06:01 +0100 Message-Id: <1415970374-16811-9-git-send-email-mreitz@redhat.com> In-Reply-To: <1415970374-16811-1-git-send-email-mreitz@redhat.com> References: <1415970374-16811-1-git-send-email-mreitz@redhat.com> Subject: [Qemu-devel] [PATCH v2 08/21] qcow2: More helpers for refcount modification List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Kevin Wolf , Peter Lieven , Stefan Hajnoczi , Max Reitz Add helper functions for getting and setting refcounts in a refcount array for any possible refcount order, and choose the correct one during refcount initialization. Signed-off-by: Max Reitz --- block/qcow2-refcount.c | 146 ++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 144 insertions(+), 2 deletions(-) diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c index b3ca7d2..2e13a9c 100644 --- a/block/qcow2-refcount.c +++ b/block/qcow2-refcount.c @@ -32,10 +32,73 @@ static int QEMU_WARN_UNUSED_RESULT update_refcount(BlockDriverState *bs, int64_t offset, int64_t length, int addend, enum qcow2_discard_type type); +static uint64_t get_refcount_ro0(const void *refcount_array, uint64_t index); +static uint64_t get_refcount_ro1(const void *refcount_array, uint64_t index); +static uint64_t get_refcount_ro2(const void *refcount_array, uint64_t index); +static uint64_t get_refcount_ro3(const void *refcount_array, uint64_t index); static uint64_t get_refcount_ro4(const void *refcount_array, uint64_t index); +static uint64_t get_refcount_ro5(const void *refcount_array, uint64_t index); +static uint64_t get_refcount_ro6(const void *refcount_array, uint64_t index); +static void set_refcount_ro0(void *refcount_array, uint64_t index, + uint64_t value); +static void set_refcount_ro1(void *refcount_array, uint64_t index, + uint64_t value); +static void set_refcount_ro2(void *refcount_array, uint64_t index, + uint64_t value); +static void set_refcount_ro3(void *refcount_array, uint64_t index, + uint64_t value); static void set_refcount_ro4(void *refcount_array, uint64_t index, uint64_t value); +static void set_refcount_ro5(void *refcount_array, uint64_t index, + uint64_t value); +static void set_refcount_ro6(void *refcount_array, uint64_t index, + uint64_t value); + +static void get_refcount_functions(int refcount_order, + Qcow2GetRefcountFunc **get, + Qcow2SetRefcountFunc **set) +{ + switch (refcount_order) { + case 0: + *get = &get_refcount_ro0; + *set = &set_refcount_ro0; + break; + + case 1: + *get = &get_refcount_ro1; + *set = &set_refcount_ro1; + break; + + case 2: + *get = &get_refcount_ro2; + *set = &set_refcount_ro2; + break; + + case 3: + *get = &get_refcount_ro3; + *set = &set_refcount_ro3; + break; + + case 4: + *get = &get_refcount_ro4; + *set = &set_refcount_ro4; + break; + + case 5: + *get = &get_refcount_ro5; + *set = &set_refcount_ro5; + break; + + case 6: + *get = &get_refcount_ro6; + *set = &set_refcount_ro6; + break; + + default: + abort(); + } +} /*********************************************************/ @@ -47,8 +110,8 @@ int qcow2_refcount_init(BlockDriverState *bs) unsigned int refcount_table_size2, i; int ret; - s->get_refcount = &get_refcount_ro4; - s->set_refcount = &set_refcount_ro4; + get_refcount_functions(s->refcount_order, + &s->get_refcount, &s->set_refcount); assert(s->refcount_table_size <= INT_MAX / sizeof(uint64_t)); refcount_table_size2 = s->refcount_table_size * sizeof(uint64_t); @@ -80,6 +143,59 @@ void qcow2_refcount_close(BlockDriverState *bs) } +static uint64_t get_refcount_ro0(const void *refcount_array, uint64_t index) +{ + return (((const uint8_t *)refcount_array)[index / 8] >> (index % 8)) & 0x1; +} + +static void set_refcount_ro0(void *refcount_array, uint64_t index, + uint64_t value) +{ + assert(!(value >> 1)); + ((uint8_t *)refcount_array)[index / 8] &= ~(0x1 << (index % 8)); + ((uint8_t *)refcount_array)[index / 8] |= value << (index % 8); +} + +static uint64_t get_refcount_ro1(const void *refcount_array, uint64_t index) +{ + return (((const uint8_t *)refcount_array)[index / 4] >> (2 * (index % 4))) + & 0x3; +} + +static void set_refcount_ro1(void *refcount_array, uint64_t index, + uint64_t value) +{ + assert(!(value >> 2)); + ((uint8_t *)refcount_array)[index / 4] &= ~(0x3 << (2 * (index % 4))); + ((uint8_t *)refcount_array)[index / 4] |= value << (2 * (index % 4)); +} + +static uint64_t get_refcount_ro2(const void *refcount_array, uint64_t index) +{ + return (((const uint8_t *)refcount_array)[index / 2] >> (4 * (index % 2))) + & 0xf; +} + +static void set_refcount_ro2(void *refcount_array, uint64_t index, + uint64_t value) +{ + assert(!(value >> 4)); + ((uint8_t *)refcount_array)[index / 2] &= ~(0xf << (4 * (index % 2))); + ((uint8_t *)refcount_array)[index / 2] |= value << (4 * (index % 2)); +} + +static uint64_t get_refcount_ro3(const void *refcount_array, uint64_t index) +{ + return ((const uint8_t *)refcount_array)[index]; +} + +static void set_refcount_ro3(void *refcount_array, uint64_t index, + uint64_t value) +{ + assert(!(value >> 8)); + ((uint8_t *)refcount_array)[index] = value; +} + static uint64_t get_refcount_ro4(const void *refcount_array, uint64_t index) { return be16_to_cpu(((const uint16_t *)refcount_array)[index]); @@ -92,6 +208,32 @@ static void set_refcount_ro4(void *refcount_array, uint64_t index, ((uint16_t *)refcount_array)[index] = cpu_to_be16(value); } +static uint64_t get_refcount_ro5(const void *refcount_array, uint64_t index) +{ + return be32_to_cpu(((const uint32_t *)refcount_array)[index]); +} + +static void set_refcount_ro5(void *refcount_array, uint64_t index, + uint64_t value) +{ + assert(!(value >> 32)); + ((uint32_t *)refcount_array)[index] = cpu_to_be32(value); +} + +static uint64_t get_refcount_ro6(const void *refcount_array, uint64_t index) +{ + return be64_to_cpu(((const uint64_t *)refcount_array)[index]); +} + +static void set_refcount_ro6(void *refcount_array, uint64_t index, + uint64_t value) +{ + /* for 64 bit refcounts, refcount_max is INT64_MAX to prevent signed + * overflows (and to allow for -errno style return values) */ + assert(!(value >> 63)); + ((uint64_t *)refcount_array)[index] = cpu_to_be64(value); +} + static int load_refcount_block(BlockDriverState *bs, int64_t refcount_block_offset, -- 1.9.3